Pension and Employee Benefit Plans - Disclosure of Fair Value Measurements of Pension Plan Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Pension assets, at fair value	$ 24,063	$ 25,296
Equity Securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Pension assets, at fair value	16,153	13,187
Debt Securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Pension assets, at fair value	7,016	5,712
Level 1 [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Pension assets, at fair value	24,063	25,296
Level 1 [Member] | Equity Securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Pension assets, at fair value	16,153	13,187
Level 1 [Member] | Debt Securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Pension assets, at fair value	7,016	5,712
Cash and cash equivalents [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Pension assets, at fair value	894	6,397
Cash and cash equivalents [Member] | Level 1 [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Pension assets, at fair value	$ 894	$ 6,397