Loans - Nonaccrual and Past Due Loans (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Recorded Investment, Aging [Abstract]
Nonaccrual status, days past due	90 days
90 Days or More Past Due	$ 16	$ 1,316
Purchased Credit Impaired	14,154	7,498
Loans held for investment	1,799,155	1,359,415
Commercial & Industrial [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Purchased Credit Impaired	2,432	895
Loans held for investment	788,410	681,290
Owner occupied commercial real estate [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Purchased Credit Impaired	1,248	1,655
Loans held for investment	163,592	156,961
Commerical real estate [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Purchased Credit Impaired	7,261	4,676
Loans held for investment	339,006	267,011
Construction, land & land development [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Purchased Credit Impaired	72	96
Loans held for investment	240,666	140,067
Residential mortgage [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Purchased Credit Impaired	3,141	176
Loans held for investment	257,066	106,362
Consumer and other [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Loans held for investment	10,415	7,724
Originated [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	10,006	6,197
90 Days or More Past Due	16	1,316
Total loans past due and still accruing	10,022	7,513
Nonaccrual	4,274	10,708
Current	1,546,435	1,317,796
Loans held for investment	1,560,731	1,336,017
Originated [Member] \| Commercial & Industrial [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	7,266	4,988
Total loans past due and still accruing	7,266	4,988
Nonaccrual	1,789	7,345
Current	750,755	662,288
Loans held for investment	759,810	674,621
Originated [Member] \| Owner occupied commercial real estate [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	1,464	780
90 Days or More Past Due		536
Total loans past due and still accruing	1,464	1,316
Nonaccrual	173
Current	146,560	152,191
Loans held for investment	148,197	153,507
Originated [Member] \| Commerical real estate [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
90 Days or More Past Due		780
Total loans past due and still accruing		780
Nonaccrual		164
Current	308,521	253,894
Loans held for investment	308,521	254,838
Originated [Member] \| Construction, land & land development [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	677
Total loans past due and still accruing	677
Nonaccrual	940	587
Current	228,526	139,280
Loans held for investment	230,143	139,867
Originated [Member] \| Residential mortgage [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	382	221
90 Days or More Past Due	16
Total loans past due and still accruing	398	221
Nonaccrual	1,277	1,328
Current	105,600	104,339
Loans held for investment	107,275	105,888
Originated [Member] \| Consumer and other [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	217	208
Total loans past due and still accruing	217	208
Nonaccrual	95	1,284
Current	6,473	5,804
Loans held for investment	6,785	7,296
Acquired [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	4,314	24
Total loans past due and still accruing	4,314	24
Nonaccrual	570	652
Purchased Credit Impaired	14,154	7,498
Current	219,386	15,224
Loans held for investment	238,424	23,398
Acquired [Member] \| Commercial & Industrial [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	137
Total loans past due and still accruing	137
Purchased Credit Impaired	2,432	895
Current	26,031	5,774
Loans held for investment	28,600	6,669
Acquired [Member] \| Owner occupied commercial real estate [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Purchased Credit Impaired	1,248	1,655
Current	14,147	1,799
Loans held for investment	15,395	3,454
Acquired [Member] \| Commerical real estate [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	1,141
Total loans past due and still accruing	1,141
Nonaccrual	570	652
Purchased Credit Impaired	7,261	4,676
Current	21,513	6,845
Loans held for investment	30,485	12,173
Acquired [Member] \| Construction, land & land development [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	2,048
Total loans past due and still accruing	2,048
Purchased Credit Impaired	72	96
Current	8,403	104
Loans held for investment	10,523	200
Acquired [Member] \| Residential mortgage [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	981
Total loans past due and still accruing	981
Purchased Credit Impaired	3,141	176
Current	145,669	298
Loans held for investment	149,791	474
Acquired [Member] \| Consumer and other [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
30-89 Past Due	7	24
Total loans past due and still accruing	7	24
Current	3,623	404
Loans held for investment	$ 3,630	$ 428

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.

+ Details

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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)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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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

+ Details

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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

+ Details

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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

+ Details

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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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