Amount of direct write-downs of accounts receivable charged against the allowance.

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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 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 credit loss expense (reversal of expense) for financing receivable from change in methodology.

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

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Loans and Allowance for Credit Losses (ALLL Rollforward) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan and lease losses, beginning of period				$ 257,323				$ 108,671	$ 257,323	$ 108,671	$ 109,931
Provision for (recovery of) credit losses	$ 246	$ (11,842)	$ (27,534)	(27,989)	$ (1,643)	$ 29,232	$ 25,414	125,428	(67,119)	178,431	8,904
Charge-offs									(71,250)	(69,602)	(17,541)
Recoveries									4,840	8,610	7,377
Allowance for loan and lease losses, end of period	126,457				257,323				126,457	257,323	108,671
Residential Portfolio Segment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan and lease losses, beginning of period				18,719				11,154	18,719	11,154	10,788
Charge-offs									(304)	(31)	0
Recoveries									13	54	212
Allowance for loan and lease losses, end of period	9,187				18,719				9,187	18,719	11,154
Commercial Portfolio Segment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan and lease losses, beginning of period				$ 238,604				97,517	238,604	97,517	99,143
Charge-offs									(70,946)	(69,571)	(17,541)
Recoveries									4,827	8,556	7,165
Allowance for loan and lease losses, end of period	$ 117,270				$ 238,604				117,270	238,604	97,517
Accounting Standards Update 2016-13 [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan and lease losses, beginning of period								135,976		135,976
Impact of adoption of ASU 2016-13										27,305
Allowance for loan and lease losses, end of period											135,976
Accounting Standards Update 2016-13 [Member] \| Residential Portfolio Segment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan and lease losses, beginning of period								19,252		19,252
Impact of adoption of ASU 2016-13										8,098
Allowance for loan and lease losses, end of period											19,252
Accounting Standards Update 2016-13 [Member] \| Commercial Portfolio Segment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan and lease losses, beginning of period								$ 116,724		116,724
Impact of adoption of ASU 2016-13										19,207
Allowance for loan and lease losses, end of period											116,724
Funded Loans [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Provision for (recovery of) credit losses									64,456	182,339	8,904
Funded Loans [Member] \| Residential Portfolio Segment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Provision for (recovery of) credit losses									9,241	556	154
Funded Loans [Member] \| Commercial Portfolio Segment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Provision for (recovery of) credit losses									$ 55,215	$ 182,895	$ 8,750