Earnings per Share - Computation of Basic and Diluted Earnings Per Share, Including Antidilutive Securities Excluded from Computation of Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2016 |
Sep. 30, 2016 |
Jun. 30, 2016 |
Mar. 31, 2016 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Numerator (Basic and Diluted): | |||||||||||
| Net income | $ 8,480 | $ 15,475 | $ 15,569 | $ 12,000 | $ 17,174 | $ 15,144 | $ 17,524 | $ 14,815 | $ 51,524 | $ 64,657 | $ 66,350 |
| Denominator: | |||||||||||
| Weighted Average Common Shares Issued and Outstanding | 38,142 | 37,637 | 37,141 | ||||||||
| Deduct: Unvested RSAs | (29) | (36) | (43) | ||||||||
| Add: Fully vested DSUs | 875 | 1,298 | 1,750 | ||||||||
| Weighted Average Common Shares Outstanding | 38,988 | 38,899 | 38,848 | ||||||||
| Basic earnings per common share | $ 0.22 | $ 0.40 | $ 0.40 | $ 0.31 | $ 0.44 | $ 0.39 | $ 0.45 | $ 0.38 | $ 1.32 | $ 1.66 | $ 1.71 |
| Weighted Average Common Shares Outstanding from above | 38,988 | 38,899 | 38,848 | ||||||||
| Add: Dilutive effect of RSUs, RSAs & ESPP | 112 | 136 | 314 | ||||||||
| Weighted Average Common Shares Outstanding | 39,100 | 39,035 | 39,162 | ||||||||
| Diluted earnings per common share | $ 0.22 | $ 0.39 | $ 0.40 | $ 0.31 | $ 0.44 | $ 0.39 | $ 0.45 | $ 0.38 | $ 1.32 | $ 1.66 | $ 1.69 |
| Antidilutive shares excluded from diluted earnings per common share | 512 | 516 | 79 | ||||||||
| Vesting period | 3 years | ||||||||||
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- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Shares issuable for little or no cash consideration upon the satisfaction of certain conditions (contingently issuable shares) are considered outstanding common shares and included in the computation of basic Earnings Per Share as of the date that all necessary conditions have been satisfied (in essence, when issuance of the shares is no longer contingent). Outstanding common shares that are contingently returnable (that is, subject to recall) are treated in the same manner as contingently issuable shares. Contingently issuable shares include shares that (a) will be issued in the future upon the satisfaction of specified conditions, (b) have been placed in escrow and all or part must be returned if specified conditions are not met, or (c) have been issued but the holder must return all or part if specified conditions are not met. The number of contingently issuable shares is determined by relating the portion of time within a reporting period that these shares have been outstanding to the total time in that period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This element represents the weighted average total number of shares issued throughout the period including the first (beginning balance outstanding) and last (ending balance outstanding) day of the period before considering any reductions (for instance, shares held in treasury) to arrive at the weighted average number of shares outstanding. Weighted average relates to the portion of time within a reporting period that common shares have been issued and outstanding to the total time in that period. Such concept is used in determining the weighted average number of shares outstanding for purposes of calculating earnings per share (basic). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of shares of restricted stock determined by relating the portion of time within a reporting period that restricted shares have been outstanding to the total time in that period. Restricted shares are subject to sales, contractual, regulatory or other restrictions that prevent or inhibit the holder from freely disposing of them before the restriction ends. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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