Loans - Age Analysis of Loans (Details 6) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual status, days past due	90 days
Financing Receivable, Recorded Investment, Aging [Abstract]
90 Days or More Past Due	$ 7	$ 16
Purchased Credit Impaired	13,409	14,154
Loans held for investment	1,810,842	1,799,155	1,404,275
Originated [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	4,116	10,006
90 Days or More Past Due		16
Total loans past due and still accruing	4,116	10,022
Nonaccrual	6,143	4,274
Current	1,585,894	1,546,435
Loans held for investment	1,596,153	1,560,731
Acquired [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	3,486	4,314
90 Days or More Past Due	7
Total loans past due and still accruing	3,493	4,314
Nonaccrual	759	570
Purchased Credit Impaired	13,409	14,154
Current	197,028	219,386
Loans held for investment	214,689	238,424
Commercial & Industrial [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Purchased Credit Impaired	2,055	2,432
Loans held for investment	744,380	788,410	675,812
Commercial & Industrial [Member] \| Originated [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	2,898	7,266
Total loans past due and still accruing	2,898	7,266
Nonaccrual	3,319	1,789
Current	718,654	750,755
Loans held for investment	724,871	759,810
Commercial & Industrial [Member] \| Acquired [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	649	137
Total loans past due and still accruing	649	137
Purchased Credit Impaired	2,055	2,432
Current	16,805	26,031
Loans held for investment	19,509	28,600
Owner occupied commercial real estate [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Purchased Credit Impaired	1,063	1,248
Loans held for investment	166,604	163,592	152,515
Owner occupied commercial real estate [Member] \| Originated [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	379	1,464
Total loans past due and still accruing	379	1,464
Nonaccrual	1,029	173
Current	150,626	146,560
Loans held for investment	152,034	148,197
Owner occupied commercial real estate [Member] \| Acquired [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Purchased Credit Impaired	1,063	1,248
Current	13,507	14,147
Loans held for investment	14,570	15,395
Commerical real estate [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Purchased Credit Impaired	7,145	7,261
Loans held for investment	367,071	339,006	310,379
Commerical real estate [Member] \| Originated [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Current	338,709	308,521
Loans held for investment	338,709	308,521
Commerical real estate [Member] \| Acquired [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	1,139	1,141
Total loans past due and still accruing	1,139	1,141
Nonaccrual	547	570
Purchased Credit Impaired	7,145	7,261
Current	19,531	21,513
Loans held for investment	28,362	30,485
Construction, land & land development [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Purchased Credit Impaired	57	72
Loans held for investment	273,125	240,666	152,327
Construction, land & land development [Member] \| Originated [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	2	677
Total loans past due and still accruing	2	677
Nonaccrual	516	940
Current	261,888	228,526
Loans held for investment	262,406	230,143
Construction, land & land development [Member] \| Acquired [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	468	2,048
Total loans past due and still accruing	468	2,048
Purchased Credit Impaired	57	72
Current	10,194	8,403
Loans held for investment	10,719	10,523
Residential mortgage [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Purchased Credit Impaired	3,089	3,141
Loans held for investment	249,591	257,066	107,408
Residential mortgage [Member] \| Originated [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	728	382
90 Days or More Past Due		16
Total loans past due and still accruing	728	398
Nonaccrual	1,279	1,277
Current	109,156	105,600
Loans held for investment	111,163	107,275
Residential mortgage [Member] \| Acquired [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	1,201	981
Total loans past due and still accruing	1,201	981
Nonaccrual	212
Purchased Credit Impaired	3,089	3,141
Current	133,926	145,669
Loans held for investment	138,428	149,791
Consumer and other [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Loans held for investment	10,071	10,415	5,834
Consumer and other [Member] \| Originated [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	109	217
Total loans past due and still accruing	109	217
Nonaccrual		95
Current	6,861	6,473
Loans held for investment	6,970	6,785
Consumer and other [Member] \| Acquired [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	29	7
90 Days or More Past Due	7
Total loans past due and still accruing	36	7
Current	3,065	3,623
Loans held for investment	$ 3,101	$ 3,630

Financing receivables that are less than 90 days past due but more than 29 days past due.

No definition available.

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- Definition

Recorded Investment in financing receivables that are past due at the balance sheet date and still accruing interest.

+ References

No definition available.

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- Definition

The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses). This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 15

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

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- Definition

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5111-111524

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- Definition

Financing receivables that are current.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7A

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953401-111524

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

+ Details

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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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- Definition

Threshold period past due for financing receivable to write off as uncollectible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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