Selected Balance Sheet Data - Summary of Net Change in Carrying Value of Assets Held in Rabbi Trust and Deferred Compensation Liability (Detail) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2018 |
Jun. 30, 2017 |
Jun. 30, 2018 |
Jun. 30, 2017 |
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| Balance Sheet Related Disclosures [Abstract] | ||||
| Increase in the carrying value of the assets held in the rabbi trust | $ 176 | $ 170 | $ 190 | $ 369 |
| Increase in the net carrying value of the deferred compensation obligation | $ 188 | $ 188 | $ 188 | $ 399 |
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- Definition The amount of increase or decrease in the fair value of plan assets during the reporting period. No definition available.
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- References No definition available.
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- Definition The increase (decrease) during the reporting period in the obligation created by employee agreements whereby earned compensation will be paid in the future. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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