Employee Benefit Plans - Expected Benefit Payments (Detail) $ in Thousands	Dec. 31, 2015 USD ($)
Pension Benefit Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2016	$ 0
2017	0
2018	0
2019	0
2020	0
2021-2025	0
Total	0
Post-Employment Benefit Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2016	567
2017	561
2018	549
2019	561
2020	528
2021-2025	1,908
Total	4,674
Post-Employment Benefit Plan [Member] | Medicare Part D Subsidy Receipts [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2016	22
2017	21
2018	19
2019	18
2020	17
2021-2025	61
Total	$ 158