Derivative Financial Instruments - Derivative Financial Instruments, their Fair Values, and Balance Sheet Location (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Derivatives Fair Value [Line Items]
Asset Derivatives	$ 46,977	$ 96,167
Liability Derivatives	32,002	18,161
Interest Rate Lock Commitments
Derivatives Fair Value [Line Items]
Asset Derivatives	2,704	4,947
Liability Derivatives	0	0
Forward Commitments
Derivatives Fair Value [Line Items]
Asset Derivatives	794	0
Liability Derivatives	46	740
Interest Rate Swap Agreements
Derivatives Fair Value [Line Items]
Asset Derivatives	42,339	90,342
Liability Derivatives	29,561	17,409
Foreign Exchange Contracts
Derivatives Fair Value [Line Items]
Asset Derivatives	1,140	878
Liability Derivatives	$ 2,395	$ 12