Derivative Financial Instruments - Balance Sheet Offsetting, Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Derivative Liabilities
Gross Amounts of Recognized Liabilities	$ 271,486	$ 237,479
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Liabilities Presented in the Statement of Financial Position	271,486	237,479
Financial Instruments (Collateral)	(114,797)	(85,192)
Cash Collateral Pledged	(74,152)	(71,475)
Net Amount	82,537	80,812
Repurchase, securities lending, and similar arrangements
Securities Sold under Agreements to Repurchase, Gross	0	0
Securities Sold under Agreements to Repurchase, Asset	0	0
Securities Sold under Agreements to Repurchase	0	0
Financial Instruments (Collateral)	0	0
Cash Collateral Pledged	0	0
Net Amount	0	0
Total
Gross Amounts of Recognized Liabilities	271,486	237,479
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Liabilities Presented in the Statement of Financial Position	271,486	237,479
Financial Instruments (Collateral)	(114,797)	(85,192)
Cash Collateral Pledged	(74,152)	(71,475)
Net Amount	82,537	80,812
Foreign exchange forwards
Derivative Liabilities
Gross Amounts of Recognized Liabilities	201,492	209,131
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Liabilities Presented in the Statement of Financial Position	201,492	209,131
Derivative Liability, Not Offset, Policy Election Deduction	(61,303)	(84,547)
Cash Collateral Pledged	(58,582)	(45,367)
Net Amount	81,607	79,217
Client foreign currency options
Derivative Liabilities
Gross Amounts of Recognized Liabilities	1,040	1,702
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Liabilities Presented in the Statement of Financial Position	1,040	1,702
Derivative Liability, Not Offset, Policy Election Deduction	(491)	(645)
Cash Collateral Pledged	0	(8)
Net Amount	549	1,049
Client interest rate derivatives
Derivative Liabilities
Gross Amounts of Recognized Liabilities	68,954	26,646
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Liabilities Presented in the Statement of Financial Position	68,954	26,646
Derivative Liability, Not Offset, Policy Election Deduction	(53,003)	0
Cash Collateral Pledged	(15,570)	(26,100)
Net Amount	$ 381	$ 546