Fair Value Fair Value (Assets and liabilities measured at fair value on a nonrecurring basis) (Details) - USD ($)	Mar. 31, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Receivable, Fair Value Disclosure	$ 6,722,858,000	$ 6,794,671,000
Other Assets, Fair Value Disclosure	6,713,878,000	6,783,848,000
Other Repossessed Assets	643,000	3,300,000
Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Receivable, Fair Value Disclosure	8,153,000	9,720,000
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Receivable, Fair Value Disclosure	6,714,705,000	6,784,951,000
Other Assets, Fair Value Disclosure	6,713,878,000	6,783,848,000
Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Receivable, Fair Value Disclosure	827,000	1,103,000
Servicing Asset at Fair Value, Amount	14,021,000	13,482,000
Other Assets, Fair Value Disclosure	760,000	775,000
Other Repossessed Assets	0	2,750,000
Fair Value, Nonrecurring [Member] | Residential Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Receivable, Fair Value Disclosure	261,000	272,000
Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Servicing Asset at Fair Value, Amount	14,021,000	13,482,000
Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Receivable, Fair Value Disclosure	827,000	1,103,000
Other Assets, Fair Value Disclosure	760,000	775,000
Other Repossessed Assets	0	2,750,000
Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Residential Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Receivable, Fair Value Disclosure	261,000	272,000
Commercial Real Estate Portfolio Segment [Member] | Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Receivable, Fair Value Disclosure	566,000	831,000
Commercial Real Estate Portfolio Segment [Member] | Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Receivable, Fair Value Disclosure	566,000	831,000
Residential Real Estate [Member] | Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other Assets, Fair Value Disclosure	760,000	775,000
Residential Real Estate [Member] | Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other Assets, Fair Value Disclosure	760,000	775,000
Reported Value Measurement [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Receivable, Fair Value Disclosure	6,742,745,000	6,787,925,000
Other Assets, Fair Value Disclosure	$ 6,733,765,000	$ 6,777,102,000