Loans - Impaired Loans Individually Evaluated (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
With an allowance recorded
Related allowance	$ 13,485		$ 14,840
Recorded investment	56,151		44,993
Unpaid principal balance	56,219		45,051
Average Recorded Investment	49,465	$ 9,132
Interest Income, Accrual Method	90	53
Commercial & Industrial [Member]
With no related allowance recorded
Recorded investment	3,097		2,612
Unpaid principal balance	3,106		2,613
With an allowance recorded
Recorded investment	41,829		32,471
Unpaid principal balance	41,875		32,510
Related allowance	13,188		14,733
Recorded investment	44,926		35,083
Unpaid principal balance	44,981		35,123
Average Recorded Investment	38,929	3,222
Interest Income, Accrual Method	7	4
Real Estate Portfolio Segment [Member]
With an allowance recorded
Related allowance	297		107
Recorded investment	11,057		9,736
Unpaid principal balance	11,070		9,754
Owner occupied commercial real estate [Member]
With no related allowance recorded
Recorded investment	1,352		829
Unpaid principal balance	1,356		834
With an allowance recorded
Recorded investment	177
Unpaid principal balance	181
Related allowance	181
Average Recorded Investment	1,243	1,035
Commerical real estate [Member]
With no related allowance recorded
Recorded investment	6,848		6,946
Unpaid principal balance	6,865		6,963
With an allowance recorded
Average Recorded Investment	6,905	2,486
Interest Income, Accrual Method	81	31
Construction, land & land development [Member]
With no related allowance recorded
Recorded investment	259		268
Unpaid principal balance	259		268
With an allowance recorded
Recorded investment	199		204
Unpaid principal balance	199		204
Related allowance	86		92
Average Recorded Investment	462	795
Interest Income, Accrual Method		15
Residential mortgage [Member]
With no related allowance recorded
Recorded investment	1,997		1,423
Unpaid principal balance	1,987		1,418
With an allowance recorded
Recorded investment	225		66
Unpaid principal balance	223		67
Related allowance	30		15
Average Recorded Investment	1,787	1,380
Consumer and other [Member]
With no related allowance recorded
Recorded investment	168		174
Unpaid principal balance	168		174
With an allowance recorded
Recorded investment	168		174
Unpaid principal balance	168		$ 174
Average Recorded Investment	139	214
Interest Income, Accrual Method	$ 2	$ 3

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5258-111524

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953550-111524

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