Loans Receivable - Modified Troubled Debt Restructuring (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) loan	Dec. 31, 2014 USD ($) loan
Financing Receivable, Modifications [Line Items]
Loans modified	$ 1,900	$ 1,000
Loans by class modified as TDRs
Number of Loans | loan	7	5
Pre-Modification outstanding recorded investment	$ 1,016	$ 695
Post-Modification outstanding recorded investment	889	449
Due to reduction in interest rate	0	19
Due to extension of maturity date	757	373
Due to permanent reduction in recorded investment	132	57
Total	$ 889	$ 449
One-to-four family residential real estate loans [Member]
Loans by class modified as TDRs
Number of Loans | loan	6	4
Pre-Modification outstanding recorded investment	$ 401	$ 485
Post-Modification outstanding recorded investment	274	444
Due to reduction in interest rate	0	19
Due to extension of maturity date	142	373
Due to permanent reduction in recorded investment	132	52
Total	$ 274	$ 444
Multi-family mortgage loans [Member]
Loans by class modified as TDRs
Number of Loans | loan	1	0
Pre-Modification outstanding recorded investment	$ 615	$ 0
Post-Modification outstanding recorded investment	615	0
Due to reduction in interest rate	0
Due to extension of maturity date	615
Due to permanent reduction in recorded investment	0
Total	$ 615
Nonresidential real estate [Member]
Loans by class modified as TDRs
Due to permanent reduction in recorded investment		$ 5
Commercial loans - Secured [Member]
Loans by class modified as TDRs
Number of Loans | loan	0	1
Pre-Modification outstanding recorded investment	$ 0	$ 210
Post-Modification outstanding recorded investment	$ 0	5
Total		$ 5