Derivative Financial Instruments - Total Notional or Contractual Amounts, Fair Value, Collateral and Net Exposure of Derivative Financial Instruments (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Derivative [Line Items]
Fair Value, Net Total	$ 134,415	$ 145,632
Collateral	5,163	12,668
Net Exposure, Net	129,252	132,964
Interest rate swaps
Derivative [Line Items]
Fair value, Assets	318	810
Foreign exchange forwards
Derivative [Line Items]
Fair value, Assets	51,050	57,644
Fair value, Liabilities	(41,296)	(44,285)
Client foreign currency options
Derivative [Line Items]
Fair value, Assets	3,861	10,383
Fair value, Liabilities	(3,861)	(10,383)
Client interest rate derivatives
Derivative [Line Items]
Fair value, Assets	10,702	10,110
Fair value, Liabilities	(10,592)	(9,770)
Derivatives designated as hedging instruments | Interest rate risks | Other assets
Derivative [Line Items]
Derivative, Notional Amount	45,964	45,964
Fair value, Assets	318	810
Collateral	0	89
Net Exposure, Assets	318	721
Derivatives not designated as hedging instruments | Foreign Exchange Contract
Derivative [Line Items]
Fair Value, Net exposure	(191)	2,089
Collateral	0	0
Net Exposure, Net	(191)	2,089
Derivatives not designated as hedging instruments | Foreign Exchange Contract | Other assets
Derivative [Line Items]
Derivative, Notional Amount	93,012	219,950
Fair value, Assets	759	3,057
Collateral	0	0
Net Exposure, Assets	759	3,057
Derivatives not designated as hedging instruments | Foreign Exchange Contract | Other liability
Derivative [Line Items]
Derivative, Notional Amount	114,317	54,338
Fair value, Liabilities	(950)	(968)
Collateral	0	0
Net Exposure, Liabilities	(950)	(968)
Derivatives not designated as hedging instruments | Other derivative instruments | Other derivative contracts
Derivative [Line Items]
Fair Value, Net exposure	10,055	11,610
Collateral	5,163	12,579
Net Exposure, Net	4,892	(969)
Derivatives not designated as hedging instruments | Other derivative instruments | Other assets
Derivative [Line Items]
Net Exposure, Assets	124,233	131,123
Derivatives not designated as hedging instruments | Other derivative instruments | Other assets | Other derivative contracts
Derivative [Line Items]
Derivative, Notional Amount	813,579	775,000
Fair value, Assets	3,861	10,383
Collateral	0	0
Net Exposure, Assets	3,861	10,383
Derivatives not designated as hedging instruments | Other derivative instruments | Other assets | Client interest rate derivatives
Derivative [Line Items]
Derivative, Notional Amount	669,139	583,511
Fair value, Assets	10,702	10,110
Collateral	0	0
Net Exposure, Assets	10,702	10,110
Derivatives not designated as hedging instruments | Other derivative instruments | Other assets | Foreign Exchange Contract
Derivative [Line Items]
Derivative, Notional Amount	1,747,019	1,251,308
Fair value, Assets	50,291	54,587
Collateral	5,163	12,579
Net Exposure, Assets	45,128	42,008
Derivatives not designated as hedging instruments | Other derivative instruments | Other liability | Other derivative contracts
Derivative [Line Items]
Derivative, Notional Amount	813,579	775,000
Fair value, Liabilities	(3,861)	(10,383)
Collateral	0	0
Net Exposure, Liabilities	(3,861)	(10,383)
Derivatives not designated as hedging instruments | Other derivative instruments | Other liability | Client interest rate derivatives
Derivative [Line Items]
Derivative, Notional Amount	712,965	627,639
Fair value, Liabilities	(10,592)	(9,770)
Collateral	0	0
Net Exposure, Liabilities	(10,592)	(9,770)
Derivatives not designated as hedging instruments | Other derivative instruments | Other liability | Foreign Exchange Contract
Derivative [Line Items]
Derivative, Notional Amount	1,588,628	1,068,991
Fair value, Liabilities	(40,346)	(43,317)
Collateral	0	0
Net Exposure, Liabilities	$ (40,346)	$ (43,317)