Employee Benefit Plans - Summary of Changes in Benefit Obligations, the Fair Value of Assets, Funded Status and Amounts Recognized in the Consolidated Statements of Financial Condition (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at end of year	$ 656,025	$ 575,031
Fair value of plan assets at end of year	607,705	568,911
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Funded (deficit) at end of year	(48,320)	(6,120)
Prepaid pension asset (included in "other assets")	2,659	31,457
Accrued benefit liability (included in "other liabilities")	(50,979)	(37,577)
Net amount recognized	(48,320)	(6,120)
Actuarial net loss (gain)	143,133	93,186
Prior service cost	11,342	13,896
Net amount recognized	154,475	107,082
Pension Plans [Member] | Change in benefit obligation [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year	575,031	519,779
Service cost	670	651
Interest cost	27,636	28,266
Actuarial (gain) loss	57,057	51,401
Benefits paid	(26,420)	(21,718)
Foreign currency translation and other adjustments	22,051	(3,348)
Benefit obligation at end of year	656,025	575,031
Pension Plans [Member] | Change in plan assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year	568,911	554,988
Actual return on plan assets	33,882	29,870
Employer contributions	8,221	8,689
Benefits paid	(26,420)	(21,718)
Foreign currency translation and other adjustments	23,111	(2,918)
Fair value of plan assets at end of year	607,705	568,911
Medical Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Funded (deficit) at end of year	(5,668)	(5,362)
Accrued benefit liability (included in "other liabilities")	(5,668)	(5,362)
Net amount recognized	(5,668)	(5,362)
Actuarial net loss (gain)	50	(261)
Net amount recognized	50	(261)
Medical Plan [Member] | Change in benefit obligation [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year	5,362	5,799
Service cost	60	69
Interest cost	211	278
Actuarial (gain) loss	310	(437)
Benefits paid	(275)	(347)
Benefit obligation at end of year	5,668	5,362
Medical Plan [Member] | Change in plan assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	275	347
Benefits paid	$ (275)	$ (347)