Loans and Allowance for Credit Losses Activity in the Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 262,887	$ 269,805	$ 263,534	$ 291,940	$ 291,940
Loans charged off	3,724	2,234	7,242	19,958
Recoveries of loans previously charged off	3,272	4,539	11,593	9,128
Total net (charge-offs) recoveries	(452)	2,305	4,351	(10,830)
Provision for credit losses	11,004	(600)	5,554	(9,600)
Ending balance	282,528	271,510	282,528	271,510	263,534
Provision for credit losses	18,958	(600)	13,508	(9,600)
ACL - loans	266,838		266,838		$ 249,001
Prudential
Allowance for Loan and Lease Losses [Roll Forward]
Provision for credit losses	7,954	0	7,954	0
Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase	1,135	0	1,135	0
Off-Balance Sheet
Allowance for Loan and Lease Losses [Roll Forward]
Provision for credit losses	$ 1,400	$ 10	$ 1,200	$ 400

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of increase in allowance for credit loss on financing receivable purchased with credit deterioration.

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Amount, after recovery, of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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