Derivative Financial Instruments - Balance Sheet Offsetting, Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Derivative Assets
Gross Amounts of Recognized Assets	$ 305,306	$ 284,831
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	305,306	284,831
Financial Instruments (Collateral)	(143,203)	(144,882)
Cash Collateral Received	(38,434)	(20,553)
Net Amount	123,669	119,396
Reverse repurchase, securities borrowing, and similar arrangements
Gross Amounts of Recognized Assets	288,438	226,847
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	288,438	226,847
Financial Instruments (Collateral)	(288,438)	(226,847)
Cash Collateral Received	0	0
Net Amount	0	0
Total
Gross Amounts of Recognized Assets	593,744	511,678
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	593,744	511,678
Financial Instruments (Collateral)	(431,641)	(371,729)
Cash Collateral Received	(38,434)	(20,553)
Net Amount	123,669	119,396
Foreign exchange forwards
Derivative Assets
Gross Amounts of Recognized Assets	239,143	215,275
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	239,143	215,275
Derivative Asset, Not Offset, Policy Election Deduction	(77,667)	(75,983)
Cash Collateral Received	(38,286)	(20,550)
Net Amount	123,190	118,742
Client foreign currency options
Derivative Assets
Gross Amounts of Recognized Assets	1,040	1,702
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	1,040	1,702
Derivative Asset, Not Offset, Policy Election Deduction	(413)	(1,045)
Cash Collateral Received	(148)	(3)
Net Amount	479	654
Client interest rate derivatives
Derivative Assets
Gross Amounts of Recognized Assets	65,123	67,854
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	65,123	67,854
Derivative Asset, Not Offset, Policy Election Deduction	(65,123)	(67,854)
Cash Collateral Received	0	0
Net Amount	$ 0	$ 0