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Amount of deferred tax asset attributable to deductible temporary differences and carryforwards that are expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Carrying amount as of the balance sheet date of income taxes previously overpaid to tax authorities (such as U.S. Federal, state and local tax authorities) representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes. Also called income tax refund receivable.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Acquisitions (Details) (USD $)	12 Months Ended	0 Months Ended
Acquisitions (Details) (USD $)	Dec. 31, 2014	Oct. 17, 2014	Oct. 17, 2014 item	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Sep. 30, 2014	Mar. 26, 2015
ACQUISITIONS
Assets	$ 2,196,135,000us-gaap_Assets			$ 1,703,127,000us-gaap_Assets
Deposit	1,845,713,000us-gaap_Deposits			1,447,372,000us-gaap_Deposits
Loans And Leases Receivable Net Of Allowance	1,783,550,000			1,343,054,000
Stockholders' equity	288,405,000us-gaap_StockholdersEquity			199,218,000us-gaap_StockholdersEquity	188,211,000us-gaap_StockholdersEquity	153,423,000us-gaap_StockholdersEquity
Goodwill, initial amount recognized	14,457,000us-gaap_GoodwillAcquiredDuringPeriod
Goodwill	30,129,000us-gaap_Goodwill			15,672,000us-gaap_Goodwill	15,672,000us-gaap_Goodwill
SP Bancorp Inc And Its Wholly Owned Subsidiary Share Plus Bank [Member]
ACQUISITIONS
Assets							348,700,000
Deposit							280,500,000
Loans And Leases Receivable Net Of Allowance							248,200,000
Stockholders' equity							33,700,000
SP Bancorp Inc And Its Wholly Owned Subsidiary Share Plus Bank [Member]
ACQUISITIONS
Number of branches			4
Cash paid for entity acquired		46,400,000
Core deposit intangibles
ACQUISITIONS
Finite-lived Intangible Assets Acquired	3,467,000
Scenario, Adjustment [Member] \| SP Bancorp Inc And Its Wholly Owned Subsidiary Share Plus Bank [Member]
ACQUISITIONS
Goodwill								2,500,000
Deferred tax assets, net								3,500,000
Current tax receivable								$ 951,000
Plano Texas
ACQUISITIONS
Number of branches		2
Dallas Texas [Member]
ACQUISITIONS
Number of branches		1
Louisville, Kentucky
ACQUISITIONS
Number of branches		1