Portfolio Loans Not Covered by Loss Share ("Non-covered") - Summary of Allowance for Loan Losses for Non-covered Loans by Portfolio Class and Category (Details) (USD $)	3 Months Ended		6 Months Ended		3 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014 Non-Covered Loans	Mar. 31, 2014 Non-Covered Loans	Jun. 30, 2014 Non-Covered Loans Commercial & Industrial	Mar. 31, 2014 Non-Covered Loans Commercial & Industrial	Jun. 30, 2014 Non-Covered Loans Commercial Real Estate Owner Occupied	Mar. 31, 2014 Non-Covered Loans Commercial Real Estate Owner Occupied	Jun. 30, 2014 Non-Covered Loans Commercial Real Estate Investor Owned	Mar. 31, 2014 Non-Covered Loans Commercial Real Estate Investor Owned	Jun. 30, 2014 Non-Covered Loans Construction and Land Development	Mar. 31, 2014 Non-Covered Loans Construction and Land Development	Jun. 30, 2014 Non-Covered Loans Residential Real Estate	Mar. 31, 2014 Non-Covered Loans Residential Real Estate	Jun. 30, 2014 Non-Covered Loans Consumer & Other	Mar. 31, 2014 Non-Covered Loans Consumer & Other
Summary of Activity in the Allowance for Loan Losses by Portfolio Class and Category Based on Impairment Method [Line Items]
Impaired Financing Receivable, Interest Income, Accrual Method	$ 6,000	$ 0	$ 15,000	$ 29,000
Allowance for Loan Losses [Roll Forward]
Balance					27,905,000	27,289,000	12,858,000	12,246,000	4,357,000	4,096,000	6,375,000	6,600,000	1,987,000	2,136,000	2,076,000	2,019,000	252,000	192,000
Provision charged to expense					1,348,000	1,027,000	3,068,000	899,000	(262,000)	589,000	(2,064,000)	(9,000)	132,000	(532,000)	412,000	16,000	62,000	64,000
Losses charged off					(1,093,000)	(1,369,000)	(1,005,000)	(474,000)	(88,000)	(336,000)	0	(250,000)	0	(305,000)	0	0	0	(4,000)
Recoveries					262,000	958,000	154,000	187,000	14,000	8,000	19,000	34,000	36,000	688,000	39,000	41,000	0	0
Balance					28,422,000	27,905,000	15,075,000	12,858,000	4,021,000	4,357,000	4,330,000	6,375,000	2,155,000	1,987,000	2,527,000	2,076,000	314,000	252,000
Loans and Leases Receivable, Impaired, Commitment to Lend	$ 0		$ 0