Subsequent Events (Details) $ / shares in Units, $ in Thousands	Jan. 31, 2016 USD ($) $ / shares shares	Oct. 02, 2015 bank	Dec. 31, 2015 USD ($) $ / shares	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Subsequent Events
Total assets			$ 2,790,646	$ 2,038,897
Total Gross Loans			2,262,683	1,628,445	$ 1,243,252
Total deposits			$ 2,195,123	$ 1,630,826
Security California Bancorp [Member]
Subsequent Events
Number of branches | bank		6
Subsequent events | Security California Bancorp [Member]
Subsequent Events
Total assets	$ 715,000
Total Gross Loans	467,000
Total deposits	635,000
Consideration paid	120,000
Cash consideration	$ 788,100
Subsequent events | Security California Bancorp [Member] | Merger agreement
Subsequent Events
Number of shares of the entity that the acquired entity's shareholder will receive for each share of acquiree	0.9629
Stock option
Subsequent Events
Weighted average exercise price (in dollars per share) | $ / shares			$ 9.09
Stock option | Subsequent events | Security California Bancorp [Member]
Subsequent Events
Stock price of the acquired entity (in dollars per share) | $ / shares	$ 18.75
Number of shares of common stock issued as consideration | shares	248,459
Weighted average exercise price (in dollars per share) | $ / shares	$ 15.58