Fair Value Accounting and Measurement (IRL Quantitative Information About Level 3 Fair Value Measurements) (Details) $ in Thousands	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Measurement input pull through rate member | Valuation technique internal pricing model member | Interest Rate Lock Commitments | Minimum [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Measurements Inputs and Valuation Techniques
Interest rate derivative asset, Measurement Input	0.7987
Measurement input pull through rate member | Valuation technique internal pricing model member | Interest Rate Lock Commitments | Maximum [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Measurements Inputs and Valuation Techniques
Interest rate derivative asset, Measurement Input	1.0000
Measurement input pull through rate member | Valuation technique internal pricing model member | Interest Rate Lock Commitments | Weighted Average [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Measurements Inputs and Valuation Techniques
Interest rate derivative asset, Measurement Input	0.9039
Fair Value, Recurring [Member]
Fair Value Measurements Inputs and Valuation Techniques
Interest rate derivative asset	$ 32,501	$ 46,184
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Measurements Inputs and Valuation Techniques
Interest rate derivative asset	0	0
Fair Value, Recurring [Member] | Interest Rate Lock Commitments
Fair Value Measurements Inputs and Valuation Techniques
Interest rate derivative asset	925	1,096
Fair Value, Recurring [Member] | Interest Rate Lock Commitments | Fair Value, Inputs, Level 3 [Member]
Fair Value Measurements Inputs and Valuation Techniques
Interest rate derivative asset	$ 925	$ 1,096