Recent Acquisitions (Details) (USD $)	3 Months Ended		0 Months Ended					0 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Oct. 02, 2013 BankAsiana Item	Oct. 02, 2013 BankAsiana New Jersey Item	Oct. 02, 2013 BankAsiana New York Item	Nov. 20, 2013 Saehan	Nov. 20, 2013 Saehan Former shareholders	Nov. 20, 2013 Saehan Southern California Item	Nov. 20, 2013 Saehan Washington and New York Item	Mar. 31, 2014 BankAsiana and Saehan
2013 Acquisitions
Purchase consideration			$ 32,500,000			$ 118,200,000
Common share price paid (in dollars per share)			$ 14.25				$ 9.40
Number of branch offices operated			3	2	1			10
Cash payable for each share of acquiree (in dollars per share)						$ 0.4247
Shares of common stock issuable for each share of acquiree						0.06080
Cash payable for each unit issued or issuable of acquiree (in dollars per share)						$ 0.21235
Shares of common stock issuable for each unit issued or issuable of acquiree						0.03040
Number of shares issued pursuant to acquisition						7,200,000
Total value of shares issued pursuant to acquisition						67,800,000
Number of LPO offices operated									2
Total fair value of assets acquired			204,100,000			589,100,000
Goodwill	$ 67,528,000	$ 67,528,000	$ 10,800,000			$ 50,000,000				$ 60,800,000
Maximum period for adjustment of provisional fair values	1 year