Loans and Allowance for Credit Losses (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Loans	$ 6,411,528	$ 5,677,893
Loans, percent	100.00%	100.00%
Less: allowance for credit losses	$ (64,758)	$ (59,074)
Net loans	6,346,770	5,618,819
Commercial [Member]
Loans	$ 1,375,939	$ 1,200,728
Loans, percent	21.00%	21.00%
Income Producing - Commercial Real Estate [Member]
Loans	$ 3,047,094	$ 2,509,517
Loans, percent	48.00%	44.00%
Owner Occupied - Commercial Real Estate - [Member]
Loans	$ 755,444	$ 640,870
Loans, percent	12.00%	12.00%
Real Estate Mortgage - Residential [Member]
Loans	$ 104,357	$ 152,748
Loans, percent	2.00%	3.00%
Construction - Commercial And Residencial [Member]
Loans	$ 1,031,832	$ 1,058,569
Construction - Commercial And Residencial [Member] \| Commercial and Residential [Member]
Loans	$ 973,141	$ 932,531
Loans, percent	15.00%	16.00%
Construction - Commercial And Residencial [Member] \| C & I Owner Occupied [Member]
Loans	$ 58,691	$ 126,038
Loans, percent	1.00%	2.00%
Home Equity [Member]
Loans	$ 93,264	$ 105,096
Loans, percent	1.00%	2.00%
Other Consumer [Member]
Loans	$ 3,598	$ 10,365

Percent of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

No definition available.

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- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ 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 (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- 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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- Definition

Amount after allowance and 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 and loans held for sale.

+ 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 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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