Amount, after tax, of accumulated unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) with 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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Significant Accounting Policies - Impact of Topic 326 (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jan. 01, 2020
Allowance-debt securities available for sale
Accrued interest receivable for debt securities available for sale debt	$ 6,900
Accounting Standards Update 2016-13
Assets
Portfolio Loans, allowance for loan losses (in dollars)		$ 53,748
Accounting Standards Update 2016-13 \| Cumulative Effect, Period of Adoption, Adjusted Balance
Assets
Portfolio Loans, allowance for loan losses (in dollars)		70,581
Liabilities
Reserve for off-balance-sheet credit exposures		5,492
Accounting Standards Update 2016-13 \| Cumulative Effect, Period of Adoption, Adjustment
Assets
Portfolio Loans, allowance for loan losses (in dollars)		16,833
Liabilities
Reserve for off-balance-sheet credit exposures		5,492
Commercial Loans \| Accounting Standards Update 2016-13
Assets
Portfolio Loans, allowance for loan losses (in dollars)		18,291
Commercial Loans \| Accounting Standards Update 2016-13 \| Cumulative Effect, Period of Adoption, Adjusted Balance
Assets
Portfolio Loans, allowance for loan losses (in dollars)		19,006
Commercial Loans \| Accounting Standards Update 2016-13 \| Cumulative Effect, Period of Adoption, Adjustment
Assets
Portfolio Loans, allowance for loan losses (in dollars)		715
Commercial Real Estate Loans \| Accounting Standards Update 2016-13
Assets
Portfolio Loans, allowance for loan losses (in dollars)		21,190
Commercial Real Estate Loans \| Accounting Standards Update 2016-13 \| Cumulative Effect, Period of Adoption, Adjusted Balance
Assets
Portfolio Loans, allowance for loan losses (in dollars)		30,496
Commercial Real Estate Loans \| Accounting Standards Update 2016-13 \| Cumulative Effect, Period of Adoption, Adjustment
Assets
Portfolio Loans, allowance for loan losses (in dollars)		9,306
Real Estate Construction \| Accounting Standards Update 2016-13
Assets
Portfolio Loans, allowance for loan losses (in dollars)		3,204
Real Estate Construction \| Accounting Standards Update 2016-13 \| Cumulative Effect, Period of Adoption, Adjusted Balance
Assets
Portfolio Loans, allowance for loan losses (in dollars)		6,158
Real Estate Construction \| Accounting Standards Update 2016-13 \| Cumulative Effect, Period of Adoption, Adjustment
Assets
Portfolio Loans, allowance for loan losses (in dollars)		2,954
Retail Real Estate \| Accounting Standards Update 2016-13
Assets
Portfolio Loans, allowance for loan losses (in dollars)		10,495
Retail Real Estate \| Accounting Standards Update 2016-13 \| Cumulative Effect, Period of Adoption, Adjusted Balance
Assets
Portfolio Loans, allowance for loan losses (in dollars)		13,787
Retail Real Estate \| Accounting Standards Update 2016-13 \| Cumulative Effect, Period of Adoption, Adjustment
Assets
Portfolio Loans, allowance for loan losses (in dollars)		3,292
Retail Other \| Accounting Standards Update 2016-13
Assets
Portfolio Loans, allowance for loan losses (in dollars)		568
Retail Other \| Accounting Standards Update 2016-13 \| Cumulative Effect, Period of Adoption, Adjusted Balance
Assets
Portfolio Loans, allowance for loan losses (in dollars)		1,134
Retail Other \| Accounting Standards Update 2016-13 \| Cumulative Effect, Period of Adoption, Adjustment
Assets
Portfolio Loans, allowance for loan losses (in dollars)		$ 566