Derivative Financial Instruments Total Notional or Contractual Amounts, Fair Value, Collateral and Net Exposure of Derivative Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Derivative [Line Items]
Fair value	$ 78,947	$ 37,983
Fair value	(64,438)	(30,742)
Net Exposure Derivative Instruments	132,964	142,446
Fair value	145,632	144,346
Collateral	12,668	1,900
Derivatives designated as hedging instruments | Interest rate risks | Other Assets
Derivative [Line Items]
Notional or Contractual Amount	45,964	45,964
Fair value	810	2,768
Collateral	89	0
Net Exposure	721	2,768
Derivatives not designated as hedging instruments | Foreign Exchange Contract [Member]
Derivative [Line Items]
Fair value	2,089	140
Net Exposure Derivative Instruments	2,089	140
Collateral	0	0
Derivatives not designated as hedging instruments | Foreign Exchange Contract [Member] | Other Assets
Derivative [Line Items]
Notional or Contractual Amount	219,950	49,287
Fair value	3,057	809
Collateral	0	0
Net Exposure	3,057	809
Derivatives not designated as hedging instruments | Foreign Exchange Contract [Member] | Other liability
Derivative [Line Items]
Notional or Contractual Amount	54,338	6,586
Fair value	(968)	(669)
Net Exposure Derivative Instruments Liabilities	(968)	(669)
Collateral	0	0
Derivatives not designated as hedging instruments | Other derivative instruments | Equity warrant assets | Other Assets
Derivative [Line Items]
Notional or Contractual Amount	211,434	210,102
Fair value	131,123	137,105
Collateral	0	0
Net Exposure	131,123	137,105
Derivatives not designated as hedging instruments | Other derivative instruments | Foreign Exchange Contract [Member] | Other Assets
Derivative [Line Items]
Notional or Contractual Amount	1,251,308	935,514
Fair value	54,587	29,722
Collateral	12,579	1,900
Net Exposure	42,008	27,822
Derivatives not designated as hedging instruments | Other derivative instruments | Foreign Exchange Contract [Member] | Other liability
Derivative [Line Items]
Notional or Contractual Amount	1,068,991	841,182
Fair value	(43,317)	(24,978)
Net Exposure Derivative Instruments Liabilities	(43,317)	(24,978)
Collateral	0	0
Derivatives not designated as hedging instruments | Other derivative instruments | Other derivatives
Derivative [Line Items]
Fair value	11,610	4,333
Net Exposure Derivative Instruments	(969)	2,433
Collateral	12,579	1,900
Derivatives not designated as hedging instruments | Other derivative instruments | Other derivatives | Other Assets
Derivative [Line Items]
Notional or Contractual Amount	775,000	46,625
Fair value	10,383	706
Collateral	0	0
Net Exposure	10,383	706
Derivatives not designated as hedging instruments | Other derivative instruments | Other derivatives | Other liability
Derivative [Line Items]
Notional or Contractual Amount	775,000	46,625
Fair value	(10,383)	(706)
Net Exposure Derivative Instruments Liabilities	(10,383)	(706)
Collateral	0	0
Derivatives not designated as hedging instruments | Other derivative instruments | Client interest rate derivatives | Other Assets
Derivative [Line Items]
Notional or Contractual Amount	583,511	422,741
Fair value	10,110	3,973
Collateral	0	0
Net Exposure	10,110	3,973
Derivatives not designated as hedging instruments | Other derivative instruments | Client interest rate derivatives | Other liability
Derivative [Line Items]
Notional or Contractual Amount	627,639	422,741
Fair value	(9,770)	(4,384)
Net Exposure Derivative Instruments Liabilities	(9,770)	(4,384)
Collateral	$ 0	$ 0