Total Notional or Contractual Amounts, Fair Value, Collateral and Net Exposure of Derivative Financial Instruments (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012		Dec. 31, 2011
Derivative [Line Items]
Fair Value	$ 83,035		$ 80,825
Collateral	4,380	[1]
Net Exposure	78,655	[2]	80,825	[2]
Derivatives designated as hedging instruments | Interest rate risks | Interest rate swaps | Other assets
Derivative [Line Items]
Notional or Contractual Amount	187,393		187,393
Fair value	9,884		11,441
Collateral	4,380	[1]
Net Exposure	5,504	[2]	11,441	[2]
Derivatives not designated as hedging instruments | Currency exchange risks
Derivative [Line Items]
Fair Value	(1,311)		315
Net Exposure	(1,311)	[2]	315	[2]
Derivatives not designated as hedging instruments | Currency exchange risks | Foreign exchange forwards | Other assets
Derivative [Line Items]
Notional or Contractual Amount	16,427		68,518
Fair value	72		514
Net Exposure	72	[2]	514	[2]
Derivatives not designated as hedging instruments | Currency exchange risks | Foreign exchange forwards | Other liability
Derivative [Line Items]
Notional or Contractual Amount	77,245		6,822
Fair Value	(1,383)		(199)
Net Exposure	(1,383)	[2]	(199)	[2]
Derivatives not designated as hedging instruments | Other derivative instruments | Equity Warrant Asset | Other assets
Derivative [Line Items]
Notional or Contractual Amount	148,329		144,586
Fair value	71,404		66,953
Net Exposure	71,404	[2]	66,953	[2]
Derivatives not designated as hedging instruments | Other derivative instruments | Other derivatives
Derivative [Line Items]
Fair Value	3,058		2,116
Net Exposure	3,058	[2]	2,116	[2]
Derivatives not designated as hedging instruments | Other derivative instruments | Other derivatives | Foreign exchange forwards | Other assets
Derivative [Line Items]
Notional or Contractual Amount	404,409		387,714
Fair value	10,680		17,541
Net Exposure	10,680	[2]	17,541	[2]
Derivatives not designated as hedging instruments | Other derivative instruments | Other derivatives | Foreign exchange forwards | Other liability
Derivative [Line Items]
Notional or Contractual Amount	376,368		366,835
Fair Value	(9,029)		(16,346)
Net Exposure	(9,029)	[2]	(16,346)	[2]
Derivatives not designated as hedging instruments | Other derivative instruments | Other derivatives | Foreign currency options | Other assets
Derivative [Line Items]
Notional or Contractual Amount	133,367		75,600
Fair value	842		271
Net Exposure	842	[2]	271	[2]
Derivatives not designated as hedging instruments | Other derivative instruments | Other derivatives | Foreign currency options | Other liability
Derivative [Line Items]
Notional or Contractual Amount	133,367		75,600
Fair Value	(842)		(271)
Net Exposure	(842)	[2]	(271)	[2]
Derivatives not designated as hedging instruments | Other derivative instruments | Other derivatives | Loan conversion options | Other assets
Derivative [Line Items]
Notional or Contractual Amount	7,539		14,063
Fair value	1,409		923
Net Exposure	1,409	[2]	923	[2]
Derivatives not designated as hedging instruments | Other derivative instruments | Other derivatives | Client interest rate derivatives | Other assets
Derivative [Line Items]
Notional or Contractual Amount	39,291		39,713
Fair value	63		50
Net Exposure	63	[2]	50	[2]
Derivatives not designated as hedging instruments | Other derivative instruments | Other derivatives | Client interest rate derivatives | Other liability
Derivative [Line Items]
Notional or Contractual Amount	39,291		39,713
Fair Value	(65)		(52)
Net Exposure	$ (65)	[2]	$ (52)	[2]

[1] Cash collateral received from counterparties for our interest rate swap agreements is recorded as a component of "short-term borrowings" on our consolidated balance sheets.

[2] Net exposure for contracts in a gain position reflects the replacement cost in the event of nonperformance by all such counterparties. The credit ratings of our institutional counterparties as of March 31, 2012 remain at investment grade or higher and there were no material changes in their credit ratings for the three months ended March 31, 2012.