Income Taxes - Reconciliation of Tax Provision for Continuing Operations (Detail)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Tax provision at U.S. statutory rate	35.00%	35.00%	35.00%
Tax exempt interest	(6.70%)	(10.30%)	(17.50%)
U.S. tax on foreign earnings	3.80%	9.30%	(0.70%)
Valuation allowance on deferred tax assets	2.10%	8.60%	(191.10%)
Tax on undistributed foreign earnings	(5.60%)	(8.10%)	6.10%
Foreign tax rate differential	(3.60%)	(6.20%)	(4.80%)
State and local income tax	1.00%	1.60%	0.60%
Other adjustments	(0.60%)	(1.30%)	(0.60%)
Foreign tax holiday	(1.10%)	(1.30%)	(1.00%)
U.S. permanent items	(1.00%)	(1.00%)	(1.30%)
Audit settlements & unrecognized tax benefits	(5.00%)	0.90%	3.80%
Effective income tax rate	18.30%	27.20%	(171.50%)