Securities (Details 3) (USD $)	Mar. 31, 2015 security	Dec. 31, 2014 security
Securities
Number of securities held with unrealized loss	56	80
Total available-for-sale securities	$ 413,403,000us-gaap_AvailableForSaleSecurities	$ 384,359,000us-gaap_AvailableForSaleSecurities
Held-to-maturity, amortized cost	2,119,542,000us-gaap_HeldToMaturitySecurities	2,133,804,000us-gaap_HeldToMaturitySecurities
Callable securities, amortized cost	227,400,000af_CallableSecuritiesAmortizedCost
Accrued interest receivable for securities	6,700,000af_InterestReceivableOnSecurities	6,700,000af_InterestReceivableOnSecurities
Callable securities amortized cost, callable within one year and thereafter	211,000,000
Held-to-maturity securities, fair value	2,137,907,000	2,131,371,000
Available-for-sale debt securities, excluding mortgage-backed securities
Securities
Available-for-sale debt securities, amortized cost	98,700,000
Total available-for-sale securities	97,600,000
Held-to-maturity debt securities, excluding mortgage-backed securities
Securities
Held-to-maturity, amortized cost	129,300,000
Held-to-maturity securities, fair value	$ 129,300,000

The amortized cost of callable securities in our securities portfolio as of the balance sheet date.

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Callable securities amortized cost, callable within one year and at various times thereafter

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Carrying amount, as of the balance sheet date, of interest on securities earned but not received.

+ References

No definition available.

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- Definition

The number of investment positions determined to be temporarily impaired.

+ References

No definition available.

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This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-SubTopic 10

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Fair value of investments in debt securities classified as held-to-maturity.

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