Allowance for loans based on collective and individual evaluation of impairment by loan category.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

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

+ References

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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- Definition

Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Loans, Allowance for Loan Losses and Credit Quality (Allowance Allocations) (Details) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2016 contract	Sep. 30, 2017 USD ($) contract	Sep. 30, 2016 contract	Dec. 31, 2016 USD ($)
Allowance for loans based on collective and individual evaluation of impairment by loan category
Ending Balance: Collectively Evaluated for Impairment		$ 6,198,610		$ 5,903,916
Ending Balance: Individually Evaluated for Impairment		76,120		77,297
Financing Receivable, Net		4,471,605		4,355,968
Ending Balance: Total Loans by Group		6,289,902		5,999,605
Receivables Acquired with Deteriorated Credit Quality [Member]
Allowance for loans based on collective and individual evaluation of impairment by loan category
Financing Receivable, Net		15,172		18,392
Commercial and Industrial [Member]
Allowance for loans based on collective and individual evaluation of impairment by loan category
Ending Balance: Collectively Evaluated for Impairment		823,007		862,875
Ending Balance: Individually Evaluated for Impairment		35,515		39,178
Financing Receivable, Net		858,522		902,053
Ending Balance: Total Loans by Group		858,522		902,053
Commercial and Industrial [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Allowance for loans based on collective and individual evaluation of impairment by loan category
Financing Receivable, Net		0		0
Commercial Real Estate [Member]
Allowance for loans based on collective and individual evaluation of impairment by loan category
Ending Balance: Collectively Evaluated for Impairment		3,060,211		2,983,642
Ending Balance: Individually Evaluated for Impairment		19,018		16,813
Financing Receivable, Net		3,087,160		3,010,798
Ending Balance: Total Loans by Group		3,087,160		3,010,798
Commercial Real Estate [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Allowance for loans based on collective and individual evaluation of impairment by loan category
Financing Receivable, Net		7,931		10,343
Construction Loans [Member]
Allowance for loans based on collective and individual evaluation of impairment by loan category
Ending Balance: Collectively Evaluated for Impairment		395,267		320,391
Ending Balance: Individually Evaluated for Impairment		0		0
Financing Receivable, Net		395,267		320,391
Ending Balance: Total Loans by Group		395,267		320,391
Construction Loans [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Allowance for loans based on collective and individual evaluation of impairment by loan category
Financing Receivable, Net		0		0
Small Business [Member]
Allowance for loans based on collective and individual evaluation of impairment by loan category
Ending Balance: Collectively Evaluated for Impairment		129,676		121,855
Ending Balance: Individually Evaluated for Impairment		980		871
Financing Receivable, Net		130,656		122,726
Ending Balance: Total Loans by Group		130,656		122,726
Small Business [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Allowance for loans based on collective and individual evaluation of impairment by loan category
Financing Receivable, Net		$ 0		0
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts \| contract		1
Allowance for loans based on collective and individual evaluation of impairment by loan category
Ending Balance: Collectively Evaluated for Impairment		$ 735,454		622,392
Ending Balance: Individually Evaluated for Impairment		13,649		14,175
Ending Balance: Total Loans by Group		756,130		644,426
Residential Real Estate [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Allowance for loans based on collective and individual evaluation of impairment by loan category
Financing Receivable, Net		7,027		7,859
Consumer Home Equity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts \| contract	1		1
Allowance for loans based on collective and individual evaluation of impairment by loan category
Ending Balance: Collectively Evaluated for Impairment		1,045,445		982,095
Ending Balance: Individually Evaluated for Impairment		6,636		5,863
Ending Balance: Total Loans by Group		1,052,295		988,147
Consumer Home Equity [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Allowance for loans based on collective and individual evaluation of impairment by loan category
Financing Receivable, Net		214		189
Consumer Other [Member]
Allowance for loans based on collective and individual evaluation of impairment by loan category
Ending Balance: Collectively Evaluated for Impairment		9,550		10,666
Ending Balance: Individually Evaluated for Impairment		322		397
Ending Balance: Total Loans by Group		9,872		11,064
Consumer Other [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Allowance for loans based on collective and individual evaluation of impairment by loan category
Financing Receivable, Net		$ 0		$ 1