Loans and Allowance for Credit Losses (Details 2) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Recorded investment in loans:
Loans individually evaluated for impairment	$ 30,191	$ 34,471
Loans collectively evaluated for impairment	6,381,337	5,643,422
Net loans	6,411,528	5,677,893
Commercial [Member]
Recorded investment in loans:
Loans individually evaluated for impairment	8,726	10,437
Loans collectively evaluated for impairment	1,367,213	1,190,291
Net loans	1,375,939	1,200,728
Income Producing - Commercial Real Estate [Member]
Recorded investment in loans:
Loans individually evaluated for impairment	10,192	15,057
Loans collectively evaluated for impairment	3,036,902	2,494,460
Net loans	3,047,094	2,509,517
Owner Occupied - Commercial Real Estate - [Member]
Recorded investment in loans:
Loans individually evaluated for impairment	5,501	2,093
Loans collectively evaluated for impairment	749,943	638,777
Net loans	755,444	640,870
Real Estate Mortgage - Residential [Member]
Recorded investment in loans:
Loans individually evaluated for impairment	478	241
Loans collectively evaluated for impairment	103,879	152,507
Net loans	104,357	152,748
Construction - Commercial And Residencial [Member]
Recorded investment in loans:
Loans individually evaluated for impairment	4,709	6,517
Loans collectively evaluated for impairment	1,027,123	1,052,052
Net loans	1,031,832	1,058,569
Home Equity [Member]
Recorded investment in loans:
Loans individually evaluated for impairment	494
Loans collectively evaluated for impairment	92,770	105,096
Net loans	93,264	105,096
Other Consumer [Member]
Recorded investment in loans:
Loans individually evaluated for impairment	91	126
Loans collectively evaluated for impairment	3,507	10,239
Net loans	$ 3,598	$ 10,365

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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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