Pension Plans - Amount Recognized in Accumulated Other Comprehensive Loss Related to Pension Plan (Detail) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Compensation Income Net Of Tax [Abstract] | |||
| Beginning Balance | $ (6,216) | $ (6,988) | |
| Pre-tax amortized net actuarial loss | 522 | 583 | |
| Tax provision | (196) | (219) | |
| Net of reclassification adjustments | 326 | 364 | $ 10 |
| Pretax gain | 56 | 653 | |
| Tax provision | (21) | (245) | |
| Net of tax adjustment to recognize (loss) gain on unfunded pension obligations | 35 | 408 | (5,112) |
| Ending Balance | $ (5,855) | $ (6,216) | $ (6,988) |