Stockholders' Equity - AOCI Reclassifications (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Stockholders' Equity [Line Items]
Realized gain on sale of securities	$ (34,948)	$ (19,833)	$ (7,493)
OTTI recognized in earnings	0	0	(1,200)
Total Swaps designated as cash flow hedges	447	0	0
Accumulated Other Comprehensive Income/(Loss)
Other-than-temporary impairments recognized in accumulated other comprehensive(loss)/income	629	609
Reclassification out of Accumulated Other Comprehensive Income
Stockholders' Equity [Line Items]
Realized gain on sale of securities	(34,948)	(19,833)	(7,493)
OTTI recognized in earnings	0	0	(1,200)
Total Available-for-sale MBS	(34,948)	(19,833)	(8,693)
Total Swaps designated as cash flow hedges	447	0	0
Total reclassifications for period	(34,501)	(19,833)	(8,693)
Reclassification out of Accumulated Other Comprehensive Income \| De-designated Swaps
Stockholders' Equity [Line Items]
Total Swaps designated as cash flow hedges	$ 447	$ 0	$ 0

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- Definition

Total of accumulated other comprehensive loss related to that portion of other than temporary impairment (OTTI) due to factors other than credit losses on debt securities categorized either as available-for-sale or held-to-maturity that an entity does not intend to sell and which it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis of the debt security. The amount represented by this item is net of tax, as applicable.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

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- Definition

Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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- Definition

Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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