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Acquisitions (Details) (USD $)					0 Months Ended		0 Months Ended
Acquisitions (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2013	Dec. 31, 2012	May 05, 2014 SP Bancorp Inc And Its Wholly Owned Subsidiary Share Plus Bank [Member] item	Jun. 30, 2014 SP Bancorp Inc And Its Wholly Owned Subsidiary Share Plus Bank [Member]	May 05, 2014 SP Bancorp Inc And Its Wholly Owned Subsidiary Share Plus Bank [Member] Plano Texas item	May 05, 2014 SP Bancorp Inc And Its Wholly Owned Subsidiary Share Plus Bank [Member] Dallas Texas [Member] item	May 05, 2014 SP Bancorp Inc And Its Wholly Owned Subsidiary Share Plus Bank [Member] KENTUCKY item
ACQUISITIONS
Aggregate cash consideration					$ 46,200,000
Number of branches					4		2	1	1
Balance sheet related disclosures
Loans Receivable	1,417,997,000	1,343,054,000				250,200,000
Deposits	1,534,572,000	1,447,372,000				268,900,000
Stockholders' equity	$ 208,752,000	$ 199,218,000	$ 192,183,000	$ 188,211,000		$ 33,400,000