Consumer and other retail loans charged off past due period.

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- Definition

Financing Receivable, Deferral Period

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Financing Receivable, Second Deferral Period

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- Definition

Loans and the allowance for loan losses.

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- Definition

Mortgage and commercial loans discontinued past due period.

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No definition available.

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- Definition

Nonperforming loans charged off past due period.

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No definition available.

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- Definition

Number of Restructured Loans

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Maximum duration past due for restructured loans to be considered performing.

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- Definition

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

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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- Definition

Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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- Definition

Amount of interest income on financing receivable on nonaccrual status.

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- Definition

Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring.

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

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Non Purchased Loans - Narrative (Details)	3 Months Ended			9 Months Ended
Non Purchased Loans - Narrative (Details)	Sep. 30, 2020 USD ($) loan	Mar. 31, 2020	Sep. 30, 2019 USD ($) loan	Sep. 30, 2020 USD ($) loan	Sep. 30, 2019 USD ($) loan	Jun. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)	Jun. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)
Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Outstanding balance of restructured loans	$ 10,916,640,000			$ 10,916,640,000			$ 9,637,476,000
Allowance for loan losses attributable to restructured loans	168,098,000		$ 50,814,000	$ 168,098,000	$ 50,814,000	$ 145,387,000	$ 52,162,000	$ 50,059,000	$ 49,026,000
Non purchased loans and leases
Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Mortgage and commercial loans discontinued past due period				90 days
Consumer and other retail loans charged-off past due period				120 days
Interest income				$ 189,000
Troubled debt restructured that has subsequently defaulted				$ 420,000	$ 61,000
Nonperforming loans charged-off past due period				90 days
Number of restructured loans \| loan				1	1
Restructured loans discontinued past due period				90 days	90 days
Remaining availability under commitments to lend additional funds on restructured loans	$ 0		$ 1,000	$ 0	$ 1,000
Number of loan modifications \| loan	8		1	34	6
Modified loans, balance	$ 832,000		$ 16,000	$ 7,802,000	$ 508,000
Non purchased loans and leases \| Loan deferral \| Loan Deferral Program, CARES Act
Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Initial deferral period		90 days
Second deferral period		90 days
Number of loan modifications \| loan				804
Modified loans, balance				$ 373,000,000
Non purchased loans and leases \| Nonaccruing Loans
Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Outstanding balance of restructured loans	92,000		40,000	92,000	40,000
Non purchased loans and leases \| Restructured loans
Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Outstanding balance of restructured loans	3,703,000		3,101,000	3,703,000	3,101,000
Allowance for loan losses attributable to restructured loans	$ 279,000		$ 30,000	$ 279,000	$ 30,000