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	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Residential mortgage servicing rights, at fair value	$ 94,346	$ 115,010	$ 158,946	$ 169,025
Asset Derivatives	383,884	150,574
Junior subordinated debentures, at fair value	195,521	274,812
Residential mortgage servicing rights
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Residential mortgage servicing rights, at fair value	94,346
Interest rate lock commitments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Asset Derivatives	23,727	7,056
Junior subordinated debentures
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Junior subordinated debentures, at fair value	195,521
Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Residential mortgage servicing rights, at fair value	94,436	115,010
Junior subordinated debentures, at fair value	195,521	274,812
Level 3 | Interest rate lock commitments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Asset Derivatives	$ 23,727	$ 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	0.1553
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	0.0973
Level 3 | Discounted cash flow | Residential mortgage servicing rights | Minimum [Member] | Constant prepayment rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Servicing asset, measurement input	0.1194
Level 3 | Discounted cash flow | Residential mortgage servicing rights | Minimum [Member] | Discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Servicing asset, measurement input	0.095
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	0.6865
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	0.125
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	0.0696
Level 3 | Discounted cash flow | Junior subordinated debentures | Minimum [Member] | Credit spread
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt instrument, measurement input	0.0534
Level 3 | Discounted cash flow | Junior subordinated debentures | Maximum | Credit spread
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt instrument, measurement input	0.0797
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	0.8474
Level 3 | Internal pricing model | Interest rate lock commitments | Minimum [Member] | Pull-through rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	0.5136
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