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 Loan Losses Allowance by Impairment Analysis Method (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Impairment Recorded investment (loan balance)	$ 20,547		$ 15,643
Individually Evaluated for Impairment Allowance for loan losses	1,076		1,235
Collectively Evaluated for Impairment Recorded investment (loan balance)	7,046,604		6,877,515
Collectively Evaluated for Impairment Allowance for loan losses	74,283		74,077
Total Loans Receivable	7,067,151		6,893,158
Allowance for loan losses	75,359	$ 75,067	75,312	$ 73,500	$ 73,464	$ 74,742
Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Impairment Recorded investment (loan balance)	1,017		3,205
Individually Evaluated for Impairment Allowance for loan losses	341		598
Collectively Evaluated for Impairment Recorded investment (loan balance)	1,142,500		1,071,503
Collectively Evaluated for Impairment Allowance for loan losses	16,197		15,314
Total Loans Receivable	1,143,517		1,074,708
Allowance for loan losses	16,538	16,082	15,912	14,455	12,381	11,735
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Impairment Recorded investment (loan balance)	0		546
Individually Evaluated for Impairment Allowance for loan losses	0		0
Collectively Evaluated for Impairment Recorded investment (loan balance)	2,533,346		2,395,146
Collectively Evaluated for Impairment Allowance for loan losses	43,006		41,934
Total Loans Receivable	2,533,346		2,395,692
Allowance for loan losses	43,006	43,741	41,934	42,824	45,183	46,820
Construction and land
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Impairment Recorded investment (loan balance)	0		0
Individually Evaluated for Impairment Allowance for loan losses	0		0
Collectively Evaluated for Impairment Recorded investment (loan balance)	209,741		240,306
Collectively Evaluated for Impairment Allowance for loan losses	4,786		6,022
Total Loans Receivable	209,741		240,306
Allowance for loan losses	4,786	4,780	6,022	4,785	4,613	4,949
Residential
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Impairment Recorded investment (loan balance)	16,938		9,183
Individually Evaluated for Impairment Allowance for loan losses	712		75
Collectively Evaluated for Impairment Recorded investment (loan balance)	2,947,104		2,939,790
Collectively Evaluated for Impairment Allowance for loan losses	9,460		9,951
Total Loans Receivable	2,964,042		2,948,973
Allowance for loan losses	10,172	9,555	10,026	9,948	9,804	9,773
Home equity
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Impairment Recorded investment (loan balance)	2,592		2,709
Individually Evaluated for Impairment Allowance for loan losses	23		562
Collectively Evaluated for Impairment Recorded investment (loan balance)	81,840		87,712
Collectively Evaluated for Impairment Allowance for loan losses	731		722
Total Loans Receivable	84,432		90,421
Allowance for loan losses	754	805	1,284	1,342	1,336	835
Consumer and other
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Impairment Recorded investment (loan balance)	0		0
Individually Evaluated for Impairment Allowance for loan losses	0		0
Collectively Evaluated for Impairment Recorded investment (loan balance)	132,073		143,058
Collectively Evaluated for Impairment Allowance for loan losses	103		134
Total Loans Receivable	132,073		143,058
Allowance for loan losses	$ 103	$ 104	$ 134	$ 146	$ 147	$ 630