Mortgage Banking Activities, Mortgage Servicing Rights (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2023 USD ($)	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)
Summary of Mortgage Servicing Rights [Abstract]
Number of residential mortgage loans serviced for others	118,303		110,541
Outstanding principal balance of residential mortgage loans serviced for others	$ 21,009,762,000		$ 18,863,201,000
Weighted average interest rate	3.55%		3.59%
Remaining term (in months)	285 months		283 months
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance	$ 277,608,000	$ 163,198,000	$ 163,198,000
Additions	2,500,000	5,215,000
Acquisitions	31,138,000	0
Changes due to principal payments	(5,384,000)	(7,960,000)
Change in fair value due to market assumption changes	(6,059,000)	49,110,000
Ending balance	$ 299,803,000	$ 209,563,000	$ 277,608,000
Servicing Assets at Fair Value, Assumptions Used to Estimate Fair Value [Abstract]
Discount rate - risk-free rate plus a market premium (in hundredths)	8.95%		9.51%
Prepayment rate - based upon loan interest rate, original term and loan type	7.43%		7.54%
Loan servicing costs - annually per loan based upon loan type, performing, minimum (in dollars per loan)	$ 69		$ 69
Loan servicing costs - annually per loan based upon loan type, performing, maximum (in dollars per loan)	94		94
Loan servicing costs - annually per loan based upon loan type, delinquent, minimum (in dollars per loan)	150		150
Loan servicing costs - annually per loan based upon loan type, delinquent, maximum (in dollars per loan)	500		500
Loan servicing costs - annually per loan based upon loan type, foreclosure, minimum (in dollars per loan)	875		875
Loan servicing costs - annually per loan based upon loan type, foreclosure, maximum (in dollars per loan)	$ 8,000		$ 8,000
Escrow earnings rate - indexed to rates paid on deposit accounts with comparable average life (in hundredths)	3.66%		4.06%
Primary secondary mortgage rate spread	105		105
Delinquency rate	1.40%		2.33%