Employee Benefit Plans - Plans' Obligation and Assets (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Change in Plan Assets
Fair value of plan assets at December 31	$ 1,288,569	$ 1,149,758
Retirement Plans [Member]
Change in Benefit Obligation
Benefit obligation at January 1	1,544,730	1,356,574
Service cost	23,551	20,796	19,647
Interest cost	69,928	70,869	71,678
Plan participant contributions	609	1,016
Plan amendments	648	1,629
Actuarial loss/(gain)	163,194	173,381
Benefits paid	(84,150)	(78,760)
Impact of foreign exchange rates	11,854	(2,999)
Other	4,192	2,224
Benefit obligation at December 31	1,734,556	1,544,730	1,356,574
Change in Plan Assets
Fair value of plan assets at January 1	1,129,042	1,043,366
Actual return on plan assets	152,907	38,916
Company contributions	65,362	132,089
Plan participant contributions	609	1,016
Benefits paid	(84,150)	(78,760)
Impact of foreign exchange rates	9,453	(1,947)
Expenses paid	(5,837)	(5,638)
Fair value of plan assets at December 31	1,267,386	1,129,042	1,043,366
Funded Status of the Plans	(467,170)	(415,688)
Retiree Health and Life Insurance Plans [Member]
Change in Benefit Obligation
Benefit obligation at January 1	38,097	40,517
Service cost	820	1,016	1,139
Interest cost	1,120	1,583	2,169
Plan participant contributions	1,229	1,514
Plan amendments		(133)
Actuarial loss/(gain)	(4,540)	(3,185)
Benefits paid	(4,158)	(3,205)
Impact of foreign exchange rates	13	(10)
Other
Benefit obligation at December 31	32,581	38,097	40,517
Change in Plan Assets
Fair value of plan assets at January 1	20,716	20,058
Actual return on plan assets	2,704	1,020
Company contributions	777	1,440
Plan participant contributions	1,229	1,514
Benefits paid	(4,158)	(3,205)
Impact of foreign exchange rates
Expenses paid	(85)	(111)
Fair value of plan assets at December 31	21,183	20,716	20,058
Funded Status of the Plans	$ (11,398)	$ (17,381)