Allowance for Credit Losses (Narrative) (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2023 USD ($)	Mar. 31, 2022 USD ($) contract	Mar. 31, 2022 USD ($) contract	Dec. 31, 2022 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Accrued interest related to financial assets held at amortized cost	$ 245,100,000	$ 124,400,000	$ 124,400,000	$ 214,000,000
Financial Asset, Amortized Cost, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Accrued interest receivable and other	Accrued interest receivable and other	Accrued interest receivable and other	Accrued interest receivable and other
Nonaccrual loans with no related allowance for credit losses	$ 23,300,000
Provision for credit losses	23,070,000	$ 4,025,000
Loan net charge-offs	(5,500,000)	(2,500,000)
Provision for credit losses	25,000	$ 81,000
Foreclosed residential real estate properties	1,100,000
TDRs, count | contract		13	57
TDRs, balance		$ 3,097,000	$ 14,839,000
Weighted average extension term		71 months
Weighted average decrease in stated interest rate		0.79%
Loan forgiveness		$ 0
Financing Receivable | Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Recorded investment, foreclosure proceedings in process	$ 53,400,000	$ 7,700,000	$ 7,700,000