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

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Allowance for Credit Losses (Gross Loan and Allowance for Credit Losses) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Ending allowance balance	$ 204,809	$ 116,539	$ 164,231
Total Loans	6,662,133	6,738,795
Originated Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1		15,091
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment		69,953
Total Ending allowance balance		85,044
Financing Receivable, Individually Evaluated for Impairment		132,324
Financing Receivable, Collectively Evaluated for Impairment		3,775,026
Total Loans		3,907,350
Mortgage Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Ending allowance balance	46,076	30,382	50,390
Mortgage Loan [Member] \| Originated Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1		6,874
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment		1,853
Total Ending allowance balance		8,727
Financing Receivable, Individually Evaluated for Impairment		71,196
Financing Receivable, Collectively Evaluated for Impairment		506,220
Total Loans		577,416
Commercial Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Ending allowance balance	62,184	34,886	60,574
Commercial Loan [Member] \| Originated Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1		8,217
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment		17,776
Total Ending allowance balance		25,993
Financing Receivable, Individually Evaluated for Impairment		61,128
Financing Receivable, Collectively Evaluated for Impairment		1,608,507
Total Loans		1,669,635
Consumer Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Ending allowance balance	25,310	18,446	17,480
Consumer Loan [Member] \| Originated Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1		0
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment		18,446
Total Ending allowance balance		18,446
Financing Receivable, Individually Evaluated for Impairment		0
Financing Receivable, Collectively Evaluated for Impairment		382,432
Total Loans		382,432
Auto Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Ending allowance balance	$ 71,239	32,825	35,787
Auto Loan [Member] \| Originated Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1		0
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment		31,878
Total Ending allowance balance		31,878
Financing Receivable, Individually Evaluated for Impairment		0
Financing Receivable, Collectively Evaluated for Impairment		1,277,867
Total Loans		1,277,867
Loans Accounted Under ASC 310-30 [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Ending allowance balance		31,495	66,981	$ 70,929
Loans Accounted Under ASC 310-30 [Member] \| Mortgage Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Ending allowance balance		21,655	30,607	29,272
Loans Accounted Under ASC 310-30 [Member] \| Commercial Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Ending allowance balance		8,893	30,226	33,674
Loans Accounted Under ASC 310-30 [Member] \| Consumer Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Ending allowance balance		0	4	22
Loans Accounted Under ASC 310-30 [Member] \| Auto Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Ending allowance balance		$ 947	$ 6,144	$ 7,961