Commitments and Contingencies - (Outstanding Financial Instruments Contract Amounts Represent Credit Risk) (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Loss Contingencies [Line Items]
Unused Commitments to Extend Credit	$ 4,332,837	$ 3,947,337
Standby letters of credit [Member]
Loss Contingencies [Line Items]
Unused Commitments to Extend Credit	135,761	139,789
Commercial letters of credit [Member]
Loss Contingencies [Line Items]
Unused Commitments to Extend Credit	13,621	6,535
Unused commitments to extend credit [Member]
Loss Contingencies [Line Items]
Unused Commitments to Extend Credit	$ 4,183,455	$ 3,801,013