Condensed Parent Company Only Financial Statements - Condensed Statements of Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Interest income:
Total interest income	$ 473,416	$ 492,350	$ 518,430
Interest expense on borrowings	95,784	98,707	113,911
Net interest expense	(340,289)	(342,288)	(341,902)
Non-interest expense:
Compensation and benefits	152,924	138,177	133,689
Extinguishment of debt	0	0	4,266
Other	32,885	35,656	35,277
Total non-interest expense	289,083	284,410	287,531
Income before income taxes and equity in undistributed earnings of subsidiaries	117,874	122,195	104,342
Income tax benefit	(29,799)	(26,279)	(37,749)
Net income	88,075	95,916	66,593
Preferred stock dividends	8,775	8,775	7,214
Net income available to common shareholders	79,300	87,141	59,379
Astoria Financial Corporation
Interest income:
ESOP loans receivable	0	0	344
Total interest income	0	0	344
Interest expense on borrowings	13,031	13,031	17,398
Net interest expense	13,031	13,031	17,054
Cash dividends from subsidiaries	64,524	40,620	45,150
Non-interest expense:
Compensation and benefits	2,820	2,925	3,261
Extinguishment of debt	0	0	4,266
Other	4,927	3,262	3,148
Total non-interest expense	7,747	6,187	10,675
Income before income taxes and equity in undistributed earnings of subsidiaries	43,746	21,402	17,421
Income tax benefit	8,056	6,662	9,644
Income before equity in undistributed earnings of subsidiaries	51,802	28,064	27,065
Equity in undistributed earnings of subsidiaries	36,273	67,852	39,528
Net income	88,075	95,916	66,593
Preferred stock dividends	8,775	8,775	7,214
Net income available to common shareholders	$ 79,300	$ 87,141	$ 59,379