Securities (Trust Preferred Securities) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Fair Value	$ 472,577	$ 481,685
Cumulative OTTI	67	0	381
Astoria Capital Trust I [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Par Amount Outstanding	5,000
Amortized Cost	5,167
Fair Value	5,171
Unrealized Gain	4
Cumulative OTTI	$ 0
Astoria Capital Trust I [Member] | Moody's, Ba1 Rating [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Debt Instrument, Credit Rating	Ba1
Astoria Capital Trust I [Member] | Standard & Poor's, BB Rating [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Debt Instrument, Credit Rating	BB
Astoria Capital Trust I [Member] | Fitch, B+ Rating [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Debt Instrument, Credit Rating	B+