Pension and Postretirement Benefits - Obligations and Funded Status (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Change in plan assets:
Fair value of plan assets at beginning of year	$ 593,927
Fair value of plan assets at end of year	532,403	$ 593,927
Amounts recognized in balance sheet consist of:
Pension liability	(24,066)	(18,403)
Domestic Plans [Member]
Change in benefit obligation:
Benefit obligation at beginning of year	556,632	583,421
Interest cost	21,613	26,972	$ 23,996
Actuarial loss (gain)	(21,754)	36,885
Terminated Vested Employees Lump-Sum Settlement		(54,551)
Benefits paid	(37,292)	(36,095)
Benefit obligation at end of year	519,199	556,632	583,421
Change in plan assets:
Fair value of plan assets at beginning of year	551,821	567,801
Actual return on plan assets	(21,889)	73,114
Company contributions	1,506	1,552
Terminated Vested Employees Lump-Sum Settlement		(54,551)
Benefits paid	(37,292)	(36,095)
Fair value of plan assets at end of year	494,146	551,821	567,801
Funded status	(25,053)	(4,811)
Amounts recognized in balance sheet consist of:
Other Assets		12,685
Accrued pension liability—current	(1,409)	(1,519)
Pension liability	(23,644)	(15,977)
Accrued benefit liability	(25,053)	(17,496)
Net (Liability)/ Asset	(25,053)	(4,811)
Plans with accumulated benefit obligation in excess of plan assets
Projected benefit obligation	519,199	556,632
Accumulated benefit obligation	519,199	556,632
Fair value of plan assets	494,146	551,821
TCN Plan [Member]
Change in benefit obligation:
Benefit obligation at beginning of year	43,985	40,396
Interest cost	1,626	1,900	1,867
Actuarial loss (gain)	(4,095)	4,438
Benefits paid	(3,251)	(2,749)
Benefit obligation at end of year	38,265	43,985	40,396
Change in plan assets:
Fair value of plan assets at beginning of year	42,106	43,483
Actual return on plan assets	(598)	1,372
Benefits paid	(3,251)	(2,749)
Fair value of plan assets at end of year	38,257	42,106	$ 43,483
Funded status	(8)	(1,879)
Amounts recognized in balance sheet consist of:
Pension liability	(8)	(1,879)
Accrued benefit liability	(8)	(1,879)
Net (Liability)/ Asset	(8)	(1,879)
Plans with accumulated benefit obligation in excess of plan assets
Projected benefit obligation	38,265	43,985
Accumulated benefit obligation	38,265	43,985
Fair value of plan assets	$ 38,257	$ 42,106