Quarterly report pursuant to Section 13 or 15(d)

Selected Balance Sheet Data - Summary of Net Change in Carrying Value of Assets Held in Rabbi Trust and Deferred Compensation Liability (Detail)

v3.7.0.1
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
Mar. 31, 2017
Mar. 31, 2016
Balance Sheet Related Disclosures [Abstract]    
Increase in the carrying value of the assets held in the rabbi trust $ 199 $ 34
Increase in the carrying value of the deferred compensation obligation $ 211 $ 37