Fair Value Measurement (Schedule Of Reconciliation Of Assets And Liabilities Measured At Fair Value Using Significant Unobservable Inputs (Level 3) On A Recurring Basis) (Details) - Level 3 - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Junior Subordinated Debentures
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Change in unrealized gains or losses for the period included in earnings for assets held at end of period	$ 11,962	$ 18,183
Change in unrealized gains or losses for the period included in other comprehensive income for assets held at end of period	(18,842)	(25,855)
Junior subordinated debentures, at fair value
Beginning Balance	274,812	300,870
Change included in earnings	11,962	18,183
Change in fair values included in comprehensive income/loss	(18,842)	(25,855)
Purchases and issuances	0	0
Sales and settlements	(12,715)	(18,386)
Ending Balance	255,217	274,812
Interest rate lock commitments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Change in unrealized gains or losses for the period included in earnings for assets held at end of period	28,144	7,056
Change in unrealized gains or losses for the period included in other comprehensive income for assets held at end of period	0	0
Interest rate lock commitments, net
Beginning Balance	7,056	6,757
Change included in earnings	15,370	5,652
Change in fair values included in comprehensive income/loss	0	0
Purchases and issuances	176,267	29,291
Sales and settlements	(170,549)	(34,644)
Ending Balance	28,144	7,056
Mortgage Servicing Rights
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Change in unrealized gains or losses for the period included in earnings for assets held at end of period	(53,423)	(19,375)
Change in unrealized gains or losses for the period included in other comprehensive income for assets held at end of period	0	0
Residential mortgage servicing rights
Beginning Balance	115,010	169,025
Change included in earnings	(73,103)	(44,783)
Change in fair values included in comprehensive income/loss	0	0
Purchases and issuances	51,000	25,169
Sales and settlements	0	(34,401)
Ending Balance	$ 92,907	$ 115,010