Purchased Loans - Narrative (Details)	3 Months Ended
Mar. 31, 2022 USD ($) loan	Mar. 31, 2021 USD ($) loan	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Loans and Allowance for Loan Losses (Textual) [Abstract]
Acquisition, at fair value	$ 28,110,000
Outstanding balance of restructured loans	10,146,991,000		$ 9,856,743,000
Troubled debt restructured that has subsequently defaulted	0	$ 0
Allowance for loan losses attributable to restructured loans	$ 166,468,000	$ 173,106,000	$ 164,171,000	$ 176,144,000
Purchased loans
Loans and Allowance for Loan Losses (Textual) [Abstract]
Number of restructured loans \| loan	0	0
Restructured loans discontinued past due period	90 days	90 days
Remaining availability under commitments to lend additional funds on restructured loans	$ 0	$ 153,000
Purchased loans \| Restructured loans
Loans and Allowance for Loan Losses (Textual) [Abstract]
Outstanding balance of restructured loans	9,944,000	19,140,000
Allowance for loan losses attributable to restructured loans	$ 69,000	$ 167,000

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Fair value at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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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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