Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Statement of Financial Position [Abstract]
Available for sale securities encumbered	$ 216,262	$ 197,896
Estimated fair value of securities held to maturity	3,691	0
Held to maturity securities encumbered	$ 2,114	$ 0
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	10,000,000us-gaap_PreferredStockSharesAuthorized	10,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, shares issued	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Preferred stock, shares outstanding	0us-gaap_PreferredStockSharesOutstanding	0us-gaap_PreferredStockSharesOutstanding
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	150,000,000us-gaap_CommonStockSharesAuthorized	150,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	58,226,326us-gaap_CommonStockSharesIssued	58,226,326us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	48,402,083us-gaap_CommonStockSharesOutstanding	57,926,233us-gaap_CommonStockSharesOutstanding
Treasury stock, shares	9,824,243us-gaap_TreasuryStockShares	300,093us-gaap_TreasuryStockShares

The fair value of available-for-sale securities that serve as collateral for borrowings.

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