Benefit Plans - Significant Unobservable Inputs Related to Pension Level 3 Assets (Details) - Level 3 - Pension Benefits - Astoria Bank	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Minimum
Significant unobservable inputs:
Composite market value factor	0.996	1.018
Gross guaranteed crediting rate	0.0285	0.0250
Maximum
Significant unobservable inputs:
Composite market value factor	1.137	1.081
Gross guaranteed crediting rate	0.0335	0.0400