Background and Basis Of Presentation Business Combination (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Nov. 06, 2015
Business Acquisition [Line Items]
Gross loans	$ 2,877,117	$ 2,862,534
Deposits	3,187,271	3,083,975
Business Combination, Premium on Non-Time Deposits			5.50%
Business Combination, Premium on Loans			1.00%
American Founders Bank [Member]
Business Acquisition [Line Items]
Gross loans	$ 108,584	$ 112,862	$ 119,000
Deposits			$ 145,000

Business Combination, Premium on Loans (%)

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- Definition

Business Combination, Premium on Non-Time Deposits (%)

+ References

No definition available.

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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 aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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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=28367877&loc=d3e4428-111522

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