Fair Value Measurement (Schedule Of A Description Of The Valuation Technique, Unobservable Input, And Qualitative Information For The Company's Assets And Liabilities Classified As Level 3) (Details) $ in Thousands	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Residential mortgage servicing rights, at fair value	$ 92,907	$ 115,010	$ 169,025	$ 153,151
Derivative assets	342,510	150,574
Junior subordinated debentures, at fair value	255,217	274,812
Residential mortgage servicing rights
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Residential mortgage servicing rights, at fair value	92,907
Interest rate lock commitments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	28,144	7,056
Junior Subordinated Debentures
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Junior subordinated debentures, at fair value	255,217
Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Residential mortgage servicing rights, at fair value	92,907	115,010
Junior subordinated debentures, at fair value	255,217	274,812
Level 3 | Interest rate lock commitments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	$ 28,144	$ 7,056
Level 3 | Discounted cash flow | Residential mortgage servicing rights | Weighted Average | Constant prepayment rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Servicing Asset, Measurement Input	0.1848
Level 3 | Discounted cash flow | Residential mortgage servicing rights | Weighted Average | Discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Servicing Asset, Measurement Input	0.0972
Level 3 | Discounted cash flow | Residential mortgage servicing rights | Minimum | Constant prepayment rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Servicing Asset, Measurement Input	0.0828
Level 3 | Discounted cash flow | Residential mortgage servicing rights | Minimum | Discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Servicing Asset, Measurement Input	0.0950
Level 3 | Discounted cash flow | Residential mortgage servicing rights | Maximum | Constant prepayment rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Servicing Asset, Measurement Input	0.7994
Level 3 | Discounted cash flow | Residential mortgage servicing rights | Maximum | Discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Servicing Asset, Measurement Input	0.1250
Level 3 | Discounted cash flow | Junior Subordinated Debentures | Weighted Average | Credit spread
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt Instrument, Measurement Input	0.0475
Level 3 | Discounted cash flow | Junior Subordinated Debentures | Minimum | Credit spread
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt Instrument, Measurement Input	0.0431
Level 3 | Discounted cash flow | Junior Subordinated Debentures | Maximum | Credit spread
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt Instrument, Measurement Input	0.0545
Level 3 | Internal pricing model | Interest rate lock commitments | Weighted Average | Pull-through rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative Asset, Measurement Input	0.8335
Level 3 | Internal pricing model | Interest rate lock commitments | Minimum | Pull-through rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative Asset, Measurement Input	0.3530
Level 3 | Internal pricing model | Interest rate lock commitments | Maximum | Pull-through rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative Asset, Measurement Input	1.0000