Loans and Allowance for Credit Losses (Details 2) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Recorded investment in loans:
Loans individually evaluated for impairment	$ 39,376	$ 30,191
Loans collectively evaluated for impairment	6,563,150	6,381,337
Net loans	6,602,526	6,411,528
Commercial [Member]
Recorded investment in loans:
Loans individually evaluated for impairment	15,468	8,726
Loans collectively evaluated for impairment	1,410,574	1,367,213
Net loans	1,426,042	1,375,939
Income Producing - Commercial Real Estate [Member]
Recorded investment in loans:
Loans individually evaluated for impairment	9,394	10,192
Loans collectively evaluated for impairment	3,128,104	3,036,902
Net loans	3,137,498	3,047,094
Owner Occupied - Commercial Real Estate - [Member]
Recorded investment in loans:
Loans individually evaluated for impairment	7,771	5,501
Loans collectively evaluated for impairment	792,976	749,943
Net loans	800,747	755,444
Real Estate Mortgage - Residential [Member]
Recorded investment in loans:
Loans individually evaluated for impairment	1,451	478
Loans collectively evaluated for impairment	102,481	103,879
Net loans	103,932	104,357
Construction - Commercial And Residencial [Member]
Recorded investment in loans:
Loans individually evaluated for impairment	4,707	4,709
Loans collectively evaluated for impairment	1,036,106	1,027,123
Net loans	1,040,813	1,031,832
Home Equity [Member]
Recorded investment in loans:
Loans individually evaluated for impairment	494	494
Loans collectively evaluated for impairment	89,777	92,770
Net loans	90,271	93,264
Other Consumer [Member]
Recorded investment in loans:
Loans individually evaluated for impairment	91	91
Loans collectively evaluated for impairment	3,132	3,507
Net loans	$ 3,223	$ 3,598

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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

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.

+ 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

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