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

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

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

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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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Allowance for Credit Losses - Summary of Allowance for Credit Losses and Recorded Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment		$ 2,200
Allowance for Loan Losses, Collectively Evaluated for Impairment		60,024
Total Allowance for Loan Losses	$ 96,850	62,224	$ 61,409	$ 6,996
Portfolio Loans, Individually Evaluated for Impairment		75,337
Portfolio Loans, Collectively Evaluated for Impairment		7,061,815
Total	$ 7,246,745	7,137,152
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment		2,023
Allowance for Loan Losses, Collectively Evaluated for Impairment		28,554
Total Allowance for Loan Losses		30,577
Portfolio Loans, Individually Evaluated for Impairment		47,920
Portfolio Loans, Collectively Evaluated for Impairment		3,368,598
Total		3,416,518
Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment		55
Allowance for Loan Losses, Collectively Evaluated for Impairment		15,626
Total Allowance for Loan Losses		15,681
Portfolio Loans, Individually Evaluated for Impairment		17,606
Portfolio Loans, Collectively Evaluated for Impairment		1,703,227
Total		1,720,833
Commercial construction
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment		113
Allowance for Loan Losses, Collectively Evaluated for Impairment		7,787
Total Allowance for Loan Losses		7,900
Portfolio Loans, Individually Evaluated for Impairment		1,914
Portfolio Loans, Collectively Evaluated for Impairment		373,531
Total		375,445
Consumer real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment		0
Allowance for Loan Losses, Collectively Evaluated for Impairment		6,337
Total Allowance for Loan Losses		6,337
Portfolio Loans, Individually Evaluated for Impairment		7,884
Portfolio Loans, Collectively Evaluated for Impairment		1,537,439
Total		1,545,323
Other consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment		9
Allowance for Loan Losses, Collectively Evaluated for Impairment		1,720
Total Allowance for Loan Losses		1,729
Portfolio Loans, Individually Evaluated for Impairment		13
Portfolio Loans, Collectively Evaluated for Impairment		79,020
Total		$ 79,033