Acquisitions (Details) (USD $)	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 30, 2014	Jan. 31, 2014	Jun. 25, 2013 item	Mar. 15, 2013 item
Acquisitions
Delinquent loans or adversely classified assets	$ 1,444,000	$ 2,251,000
LIABILITIES ASSUMED
Goodwill recognized	22,950,000	17,428,000
Cash received from FDIC	(7,793,000)	138,424,000	39,491,000
Total purchase credit impaired loans	1,601,000	1,977,000	6,319,000
Pro forma net interest and other income, net income and earnings per share
Net interest and other income	87,047,000	72,515,000
Net income	16,235,000	9,231,000
Basic earnings per share (in dollars per share)	$ 0.95	$ 0.51
Diluted earnings per share (in dollars per share)	$ 0.94	$ 0.48
Acquired Loans
Contractual amounts due, expected cash flows to be collected, interest component and fair value as of the respective acquisition dates
Contractual amounts due		177,678,000
Expected cash flows		177,678,000
Interest component of expected cash flows		29,701,000
Fair value of acquired loans		147,977,000
Infinity Franchise Holdings Acquisition
Acquisitions
Assets acquired				80,800,000	80,978,000
Liabilities acquired				709,000,000	68,326,000
Credit facility paid off				67,600,000
Delinquent loans or adversely classified assets				0
Consideration paid				16,900,000
Cash consideration				9,000,000
Number of shares of common stock issued as consideration				562,469
Stock price of the acquired entity (in dollars per share)				$ 16.02
Period prior to announcement of the transaction for which average closing price is considered to calculate value of shares to be issued				10 days
ASSETS ACQUIRED
Cash and cash equivalents					555,000
Loans, gross					78,833,000
Deferred loan costs					1,082,000
Allowance for loan losses					(268,000)
Other assets					776,000
Total assets acquired				80,800,000	80,978,000
LIABILITIES ASSUMED
Bank loan					67,617,000
Accrued compensation					495,000
Other liabilities					214,000
Total liabilities assumed				709,000,000	68,326,000
Excess of assets acquired over liabilities assumed					12,652,000
Consideration paid				16,900,000
Pro forma net interest and other income, net income and earnings per share
Credit facility paid off				67,600,000
Infinity Franchise Holdings Acquisition | As initially reported
Acquisitions
Assets acquired					(814,000)
ASSETS ACQUIRED
Deferred loan costs					(1,082,000)
Allowance for loan losses					268,000
Total assets acquired					(814,000)
LIABILITIES ASSUMED
Excess of assets acquired over liabilities assumed					(814,000)
Infinity Franchise Holdings Acquisition | Fair Value Adjustments
Acquisitions
Assets acquired					80,164,000
Liabilities acquired					68,326,000
Consideration paid					17,360,000
ASSETS ACQUIRED
Cash and cash equivalents					555,000
Loans, gross					78,833,000
Other assets					776,000
Total assets acquired					80,164,000
LIABILITIES ASSUMED
Bank loan					67,617,000
Accrued compensation					495,000
Other liabilities					214,000
Total liabilities assumed					68,326,000
Excess of assets acquired over liabilities assumed					11,838,000
Consideration paid					17,360,000
Goodwill recognized					5,522,000
San Diego Trust Bank
Acquisitions
Assets acquired						211,223,000
Liabilities acquired						186,175,000
Consideration paid						30,622,000
Cash consideration						16,200,000
Number of shares of common stock issued as consideration						1,198,255
Number of entities in business combination						2
ASSETS ACQUIRED
Cash and cash equivalents						30,252,000
Investment securities						124,805,000
Loans, gross						42,722,000
Other real estate owned						752,000
Core deposit intangible						2,836,000
Other assets						9,856,000
Total assets acquired						211,223,000
LIABILITIES ASSUMED
Deposits						183,907,000
Deferred tax liability (asset)						1,174,000
Other liabilities						1,094,000
Total liabilities assumed						186,175,000
Excess of assets acquired over liabilities assumed						25,048,000
Consideration paid						30,622,000
Goodwill recognized						5,574,000
Total purchase credit impaired loans						0
San Diego Trust Bank | As initially reported
Acquisitions
Assets acquired						207,752,000
Liabilities acquired						185,391,000
ASSETS ACQUIRED
Cash and cash equivalents						30,252,000
Investment securities						124,960,000
Loans, gross						42,945,000
Allowance for loan losses						(1,013,000)
Other real estate owned						752,000
Other assets						9,856,000
Total assets acquired						207,752,000
LIABILITIES ASSUMED
Deposits						183,901,000
Deferred tax liability (asset)						(333,000)
Other liabilities						1,823,000
Total liabilities assumed						185,391,000
Excess of assets acquired over liabilities assumed						22,361,000
San Diego Trust Bank | Fair Value Adjustments
Acquisitions
Assets acquired						3,471,000
Liabilities acquired						784,000
ASSETS ACQUIRED
Investment securities						(155,000)
Loans, gross						(223,000)
Allowance for loan losses						1,013,000
Core deposit intangible						2,836,000
Total assets acquired						3,471,000
LIABILITIES ASSUMED
Deposits						6,000
Deferred tax liability (asset)						1,507,000
Other liabilities						(729,000)
Total liabilities assumed						784,000
Excess of assets acquired over liabilities assumed						2,687,000
First Association Bank
Acquisitions
Assets acquired							424,229,000
Liabilities acquired							378,177,000
Consideration paid							57,906,000
Cash consideration							43,000,000
Number of shares of common stock issued as consideration							1,279,217
Number of entities in business combination							2
ASSETS ACQUIRED
Cash and cash equivalents							167,663,000
Investment securities							222,391,000
Loans, gross							26,422,000
Core deposit intangible							1,930,000
Other assets							5,823,000
Total assets acquired							424,229,000
LIABILITIES ASSUMED
Deposits							356,818,000
Bank loan							16,905,000
Deferred tax liability (asset)							3,918,000
Other liabilities							536,000
Total liabilities assumed							378,177,000
Excess of assets acquired over liabilities assumed							46,052,000
Consideration paid							57,906,000
Goodwill recognized							11,854,000
Total purchase credit impaired loans							0
First Association Bank | As initially reported
Acquisitions
Assets acquired							419,439,000
Liabilities acquired							374,178,000
ASSETS ACQUIRED
Cash and cash equivalents							167,663,000
Investment securities							219,913,000
Loans, gross							26,264,000
Allowance for loan losses							(224,000)
Other assets							5,823,000
Total assets acquired							419,439,000
LIABILITIES ASSUMED
Deposits							356,737,000
Bank loan							16,905,000
Other liabilities							536,000
Total liabilities assumed							374,178,000
Excess of assets acquired over liabilities assumed							45,261,000
First Association Bank | Fair Value Adjustments
Acquisitions
Assets acquired							4,790,000
Liabilities acquired							3,999,000
ASSETS ACQUIRED
Investment securities							2,478,000
Loans, gross							158,000
Allowance for loan losses							224,000
Core deposit intangible							1,930,000
Total assets acquired							4,790,000
LIABILITIES ASSUMED
Deposits							81,000
Deferred tax liability (asset)							3,918,000
Total liabilities assumed							3,999,000
Excess of assets acquired over liabilities assumed							$ 791,000
Maximum | San Diego Trust Bank
LIABILITIES ASSUMED
Extension period for measurement of fair values						1 year