Derivative Financial Instruments - Fair Value of Derivative Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Total Asset Derivatives	$ 20,057	$ 36,433
Total Liability Derivatives	24,377	43,631
Derivatives designated as hedging instruments
Derivatives, Fair Value [Line Items]
Total Asset Derivatives	19,391	35,388
Total Liability Derivatives	24,044	43,631
Derivatives designated as hedging instruments | Interest rate contracts | Other assets
Derivatives, Fair Value [Line Items]
Total Asset Derivatives	19,391	35,388
Derivatives designated as hedging instruments | Interest rate contracts | Other liabilities
Derivatives, Fair Value [Line Items]
Total Liability Derivatives	24,044	43,631
Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Total Asset Derivatives	666	1,045
Total Liability Derivatives	333	0
Derivatives not designated as hedging instruments | Mortgage loan contracts | Other assets
Derivatives, Fair Value [Line Items]
Total Asset Derivatives	666	1,045
Derivatives not designated as hedging instruments | Mortgage loan contracts | Other liabilities
Derivatives, Fair Value [Line Items]
Total Liability Derivatives	$ 333	$ 0