Loans Receivable, Net ALLL and Loans Receivable Summary (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Loans Receivable and Allowance for Loan and Lease Losses
Individually evaluated for impairment	$ 119,994	$ 130,263
Collectively evaluated for impairment	6,457,830	5,554,200
Total loans receivable	6,577,824	5,684,463
Individually evaluated for impairment	5,223	6,881
Collectively evaluated for impairment	124,345	122,691
Total allowance for loan and lease losses	129,568	129,572
Residential Real Estate \| Residential Real Estate
Loans Receivable and Allowance for Loan and Lease Losses
Individually evaluated for impairment	12,399	11,612
Collectively evaluated for impairment	708,329	662,735
Total loans receivable	720,728	674,347
Individually evaluated for impairment	246	856
Collectively evaluated for impairment	10,552	11,580
Total allowance for loan and lease losses	10,798	12,436
Commercial
Loans Receivable and Allowance for Loan and Lease Losses
Total loans receivable	5,156,492	4,332,391
Commercial \| Commercial Real Estate
Loans Receivable and Allowance for Loan and Lease Losses
Individually evaluated for impairment	77,536	85,634
Collectively evaluated for impairment	3,499,603	2,904,507
Total loans receivable	3,577,139	2,990,141
Individually evaluated for impairment	500	922
Collectively evaluated for impairment	68,015	64,851
Total allowance for loan and lease losses	68,515	65,773
Commercial \| Other Commercial
Loans Receivable and Allowance for Loan and Lease Losses
Individually evaluated for impairment	23,032	23,950
Collectively evaluated for impairment	1,556,321	1,318,300
Total loans receivable	1,579,353	1,342,250
Individually evaluated for impairment	3,851	4,419
Collectively evaluated for impairment	35,452	33,404
Total allowance for loan and lease losses	39,303	37,823
Consumer and Other
Loans Receivable and Allowance for Loan and Lease Losses
Total loans receivable	700,604	677,725
Consumer and Other \| Home Equity
Loans Receivable and Allowance for Loan and Lease Losses
Individually evaluated for impairment	3,755	5,934
Collectively evaluated for impairment	454,163	428,840
Total loans receivable	457,918	434,774
Individually evaluated for impairment	56	296
Collectively evaluated for impairment	6,148	7,276
Total allowance for loan and lease losses	6,204	7,572
Consumer and Other \| Other Consumer
Loans Receivable and Allowance for Loan and Lease Losses
Individually evaluated for impairment	3,272	3,133
Collectively evaluated for impairment	239,414	239,818
Total loans receivable	242,686	242,951
Individually evaluated for impairment	570	388
Collectively evaluated for impairment	4,178	5,580
Total allowance for loan and lease losses	$ 4,748	$ 5,968

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

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