Loans - Impaired Loans Individually Evaluated (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
With an allowance recorded
Related allowance	$ 20,177		$ 20,177		$ 14,840
Recorded investment	72,950		72,950		44,993
Unpaid principal balance	73,063		73,063		45,051
Average Recorded Investment	64,662	$ 7,531	57,064	$ 7,331	16,700
Interest Income, Accrual Method	284	260	375	296
Commercial & Industrial [Member]
With no related allowance recorded
Recorded investment	10,581		10,581		2,612
Unpaid principal balance	10,628		10,628		2,613
With an allowance recorded
Recorded investment	50,050		50,050		32,471
Unpaid principal balance	50,091		50,091		32,510
Related allowance	19,386		19,386		14,733
Recorded investment	60,631		60,631		35,083
Unpaid principal balance	60,719		60,719		35,123
Average Recorded Investment	53,587	3,739	46,258	2,480
Interest Income, Accrual Method	13	18	20	20
Real Estate Portfolio Segment [Member]
With an allowance recorded
Related allowance	789		789		107
Recorded investment	12,209		12,209		9,736
Unpaid principal balance	12,234		12,234		9,754
Owner occupied commercial real estate [Member]
With no related allowance recorded
Recorded investment	1,576		1,576		829
Unpaid principal balance	1,596		1,596		834
With an allowance recorded
Recorded investment	562		562
Unpaid principal balance	560		560
Related allowance	560		560
Average Recorded Investment	1,343	1,426	1,293	1,230
Commercial real estate [Member]
With no related allowance recorded
Recorded investment	7,290		7,290		6,946
Unpaid principal balance	7,313		7,313		6,963
With an allowance recorded
Average Recorded Investment	7,152	534	7,029	1,510
Interest Income, Accrual Method	80		162	16
Construction, land & land development [Member]
With no related allowance recorded
Recorded investment					268
Unpaid principal balance					268
With an allowance recorded
Recorded investment					204
Unpaid principal balance					204
Related allowance					92
Average Recorded Investment	151	507	307	651
Interest Income, Accrual Method	180		180	15
Residential mortgage [Member]
With no related allowance recorded
Recorded investment	2,133		2,133		1,423
Unpaid principal balance	2,120		2,120		1,418
With an allowance recorded
Recorded investment	648		648		66
Unpaid principal balance	645		645		67
Related allowance	229		229		15
Average Recorded Investment	2,345	1,173	2,066	1,277
Interest Income, Accrual Method	10	240	10	240
Consumer and other [Member]
With no related allowance recorded
Recorded investment	108		108		174
Unpaid principal balance	108		108		174
With an allowance recorded
Recorded investment	2		2
Unpaid principal balance	2		2
Related allowance	2		2
Recorded investment	110		110		174
Unpaid principal balance	110		110		$ 174
Average Recorded Investment	84	152	111	183
Interest Income, Accrual Method	$ 1	$ 2	$ 3	$ 5

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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