Stockholders' Equity (Details) (USD $)	0 Months Ended	12 Months Ended			12 Months Ended	0 Months Ended
	Jan. 07, 2014	Dec. 31, 2013	Dec. 31, 2012	Apr. 18, 2007	Dec. 31, 2013 Astoria Federal	Mar. 19, 2013 Series C Preferred Stock	Mar. 19, 2013 Depositary share
Stockholders' Equity
Shares issued (in shares)						135,000	5,400,000
Per share interest in Non-Cumulative Perpetual Preferred Stock, Series C							0.025
Dividend rate (as a percent)						6.50%
Par value (in dollars per share)		$ 1.00	$ 1.00			$ 1.00
Liquidation preference (in dollars per share)						$ 1,000	$ 25
Aggregate proceeds from the offering, net of underwriting discounts and other issuance costs		$ 129,796,000				$ 129,800,000
Redemption price (in dollars per share)						$ 1,000	$ 25
Dividend reinvestment and stock purchase plan, shares of authorized and unissued reserved for the plan	1,500,000
Maximum optional cash purchases amount per month of additional shares of common stock through the dividend reinvestment and stock purchase plan	10,000
Stock repurchase program approved				10,000,000
Percentage of common stock Outstanding				10.00%
The remaining number of shares authorized to be purchased		8,107,300
Minimum notice period required for declaring dividend					30 days
Dividend paid by Astoria Federal					$ 44,000,000