Loans and Allowance for Credit Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Loans	$ 6,602,526	$ 6,411,528
Loans, percent	100.00%	100.00%
Less: allowance for credit losses	$ (65,807)	$ (64,758)
Net loans	6,536,719	6,346,770
Commercial [Member]
Loans	$ 1,426,042	$ 1,375,939
Loans, percent	22.00%	21.00%
Income Producing - Commercial Real Estate [Member]
Loans	$ 3,137,498	$ 3,047,094
Loans, percent	47.00%	48.00%
Owner Occupied - Commercial Real Estate - [Member]
Loans	$ 800,747	$ 755,444
Loans, percent	12.00%	12.00%
Real Estate Mortgage - Residential [Member]
Loans	$ 103,932	$ 104,357
Loans, percent	2.00%	2.00%
Construction - Commercial And Residencial [Member]
Loans	$ 1,040,813	$ 1,031,832
Construction - Commercial And Residencial [Member] \| Commercial and Residential [Member]
Loans	$ 1,000,266	$ 973,141
Loans, percent	15.00%	15.00%
Construction - Commercial And Residencial [Member] \| C & I Owner Occupied [Member]
Loans	$ 40,547	$ 58,691
Loans, percent	1.00%	1.00%
Home Equity [Member]
Loans	$ 90,271	$ 93,264
Loans, percent	1.00%	1.00%
Other Consumer [Member]
Loans	$ 3,223	$ 3,598
Loans, percent

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

No definition available.

+ Details

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Period Type:	instant

- 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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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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Period Type:	instant

- 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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