Derivative Financial Instruments - Total Notional or Contractual Amounts, Fair Value, Collateral and Net Exposure of Derivative Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Derivative [Line Items]
Derivative Assets	$ 269,348	$ 167,341
Derivative Liabilities	181,214	137,984
Derivative Assets, Total	440,430	332,814
Derivative Liabilities, Total	181,214	137,984
Reduction in derivative liabilities due to rules of clearing houses	65,100	17,400
Interest rate swaps
Derivative [Line Items]
Derivative Assets	0	22,676
Derivative Liabilities	0	25,623
Foreign exchange forwards
Derivative [Line Items]
Derivative Assets	179,166	114,546
Derivative Liabilities	149,611	96,899
Client foreign currency options
Derivative [Line Items]
Derivative Assets	2,927	1,308
Derivative Liabilities	2,927	1,308
Client interest rate derivatives
Derivative [Line Items]
Derivative Assets	87,255	28,811
Derivative Liabilities	28,676	14,154
Derivatives designated as hedging instruments | Interest rate swaps | Other assets
Derivative [Line Items]
Derivative Asset, Notional or Contractual Amount	0	1,915,000
Derivative Assets	0	22,676
Derivatives designated as hedging instruments | Interest rate swaps | Other liabilities
Derivative [Line Items]
Derivative Liabilities, Notional or Contractual Amount	0	3,085,000
Derivative Liabilities	0	25,623
Derivatives not designated as hedging instruments
Derivative [Line Items]
Derivative Assets	440,430	310,138
Derivative Liabilities	181,214	112,361
Derivatives not designated as hedging instruments | Foreign exchange forwards | Other liabilities
Derivative [Line Items]
Derivative Liabilities, Notional or Contractual Amount	308,975	300,250
Derivative Liabilities	10,471	2,154
Derivatives not designated as hedging instruments | Equity warrant assets | Other assets
Derivative [Line Items]
Derivative Asset, Notional or Contractual Amount	249,399	225,893
Derivative Assets	171,082	165,473
Derivatives not designated as hedging instruments | Client foreign exchange forwards | Other assets
Derivative [Line Items]
Derivative Asset, Notional or Contractual Amount	6,937,993	4,661,517
Derivative Assets	179,166	114,546
Derivatives not designated as hedging instruments | Client foreign exchange forwards | Other liabilities
Derivative [Line Items]
Derivative Liabilities, Notional or Contractual Amount	6,339,390	4,326,059
Derivative Liabilities	139,140	94,745
Derivatives not designated as hedging instruments | Client foreign currency options | Other assets
Derivative [Line Items]
Derivative Asset, Notional or Contractual Amount	155,412	154,985
Derivative Assets	2,927	1,308
Derivatives not designated as hedging instruments | Client foreign currency options | Other liabilities
Derivative [Line Items]
Derivative Liabilities, Notional or Contractual Amount	155,412	154,985
Derivative Liabilities	2,927	1,308
Derivatives not designated as hedging instruments | Client interest rate derivatives | Other assets
Derivative [Line Items]
Derivative Asset, Notional or Contractual Amount	870,885	1,275,190
Derivative Assets	87,255	28,811
Derivatives not designated as hedging instruments | Client interest rate derivatives | Other liabilities
Derivative [Line Items]
Derivative Liabilities, Notional or Contractual Amount	977,084	1,372,914
Derivative Liabilities	$ 28,676	$ 14,154