Loans - Portfolio by Type and Class (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	$ 1,433,702	$ 1,359,415	$ 1,261,015
Originated [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	1,416,524	1,336,017
Acquired [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	17,178	23,398
Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	1,323,972	1,245,329
Commercial [Member] | Originated [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	1,307,513	1,222,833
Commercial [Member] | Acquired [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	16,459	22,496
Commercial & Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	710,915	681,290	659,757
Commercial & Industrial [Member] | Originated [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	708,773	674,621
Commercial & Industrial [Member] | Acquired [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,142	6,669
Owner occupied commercial real estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	142,484	156,961	137,767
Owner occupied commercial real estate [Member] | Originated [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	139,970	153,507
Owner occupied commercial real estate [Member] | Acquired [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,514	3,454
Commerical real estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	281,882	267,011	218,637
Commerical real estate [Member] | Originated [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	270,250	254,838
Commerical real estate [Member] | Acquired [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	11,632	12,173
Construction, land & land development [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	188,691	140,067	132,875
Construction, land & land development [Member] | Originated [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	188,520	139,867
Construction, land & land development [Member] | Acquired [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	171	200
Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	109,730	114,086
Consumer [Member] | Originated [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	109,011	113,184
Consumer [Member] | Acquired [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	719	902
Residential mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	104,913	106,362	104,327
Residential mortgage [Member] | Originated [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	104,529	105,888
Residential mortgage [Member] | Acquired [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	384	474
Other consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	4,817	7,724	7,652
Other consumer [Member] | Originated [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	4,482	7,296
Other consumer [Member] | Acquired [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	$ 335	$ 428