Derivative Financial Instruments - Total Notional or Contractual Amounts, Fair Value, Collateral and Net Exposure of Derivative Financial Instruments (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Derivative [Line Items]
Fair Value	$ 94,815	$ 113,101
Net Exposure	89,905	108,021
Collateral	4,910	5,080
Derivatives designated as hedging instruments | Interest rate risks | Interest rate swaps | Other assets
Derivative [Line Items]
Notional or Contractual Amount	45,964	45,964
Fair Value	5,692	6,492
Net Exposure	1,782	1,412
Collateral	3,910	5,080
Derivatives not designated as hedging instruments | Currency exchange risks
Derivative [Line Items]
Fair Value	(1,347)	789
Net Exposure	(1,347)	789
Derivatives not designated as hedging instruments | Currency exchange risks | Foreign exchange forwards | Other assets
Derivative [Line Items]
Notional or Contractual Amount	3,240	140,760
Fair Value	198	1,423
Net Exposure	198	1,423
Collateral	0	0
Derivatives not designated as hedging instruments | Currency exchange risks | Foreign exchange forwards | Other liability
Derivative [Line Items]
Notional or Contractual Amount	178,419	62,649
Fair Value	(1,545)	(634)
Net Exposure	(1,545)	(634)
Collateral	0	0
Derivatives not designated as hedging instruments | Other derivative instruments | Equity warrant assets | Other assets
Derivative [Line Items]
Notional or Contractual Amount	182,145	179,934
Fair Value	88,905	103,513
Net Exposure	88,905	103,513
Collateral	0	0
Derivatives not designated as hedging instruments | Other derivative instruments | Other derivatives
Derivative [Line Items]
Fair Value	1,565	2,307
Net Exposure	565	2,307
Collateral	1,000
Derivatives not designated as hedging instruments | Other derivative instruments | Other derivatives | Foreign exchange forwards | Other assets
Derivative [Line Items]
Notional or Contractual Amount	417,361	424,983
Fair Value	10,759	13,673
Net Exposure	9,759	13,673
Collateral	1,000	0
Derivatives not designated as hedging instruments | Other derivative instruments | Other derivatives | Foreign exchange forwards | Other liability
Derivative [Line Items]
Notional or Contractual Amount	347,983	367,079
Fair Value	(9,066)	(11,549)
Net Exposure	(9,066)	(11,549)
Collateral	0	0
Derivatives not designated as hedging instruments | Other derivative instruments | Other derivatives | Client foreign currency options | Other assets
Derivative [Line Items]
Notional or Contractual Amount	4,500	91,854
Fair Value	133	434
Net Exposure	133	434
Collateral	0	0
Derivatives not designated as hedging instruments | Other derivative instruments | Other derivatives | Client foreign currency options | Other liability
Derivative [Line Items]
Notional or Contractual Amount	4,500	91,854
Fair Value	(133)	(434)
Net Exposure	(133)	(434)
Collateral	0	0
Derivatives not designated as hedging instruments | Other derivative instruments | Other derivatives | Loan conversion options | Other assets
Derivative [Line Items]
Notional or Contractual Amount	1,940	3,455
Fair Value	53	314
Net Exposure	53	314
Collateral	0	0
Derivatives not designated as hedging instruments | Other derivative instruments | Other derivatives | Client interest rate derivatives | Other assets
Derivative [Line Items]
Notional or Contractual Amount	310,910	216,773
Fair Value	2,239	1,265
Net Exposure	2,239	1,265
Collateral	0	0
Derivatives not designated as hedging instruments | Other derivative instruments | Other derivatives | Client interest rate derivatives | Other liability
Derivative [Line Items]
Notional or Contractual Amount	310,910	216,773
Fair Value	(2,420)	(1,396)
Net Exposure	(2,420)	(1,396)
Collateral	$ 0	$ 0