Loans Receivable and Allowance for Loan Losses (Details 11) (Mortgage Loans (Gross), USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013 item	Jun. 30, 2012 item	Jun. 30, 2013 item	Jun. 30, 2012 item
Information about mortgage loans receivable by segment and class modified in troubled debt restructuring
Number of Loans	22	17	47	31
Pre-Modification Recorded Investment	$ 8,477	$ 12,056	$ 18,910	$ 41,554
Recorded Investment	8,395	11,933	18,275	40,082
Residential Mortgage Loans | Full documentation interest-only loans
Information about mortgage loans receivable by segment and class modified in troubled debt restructuring
Number of Loans	6	4	11	4
Pre-Modification Recorded Investment	1,296	1,060	2,451	1,060
Recorded Investment	1,295	1,046	2,450	1,046
Residential Mortgage Loans | Full documentation amortizing loans
Information about mortgage loans receivable by segment and class modified in troubled debt restructuring
Number of Loans	3		5
Pre-Modification Recorded Investment	721		1,501
Recorded Investment	718		1,506
Residential Mortgage Loans | Reduced documentation interest-only loans
Information about mortgage loans receivable by segment and class modified in troubled debt restructuring
Number of Loans	8	4	19	7
Pre-Modification Recorded Investment	2,702	1,815	6,135	2,729
Recorded Investment	2,702	1,803	6,111	2,718
Residential Mortgage Loans | Reduced documentation amortizing loans
Information about mortgage loans receivable by segment and class modified in troubled debt restructuring
Number of Loans	3	1	6	5
Pre-Modification Recorded Investment	1,342	401	2,084	1,950
Recorded Investment	1,321	393	2,045	1,851
Multi-Family
Information about mortgage loans receivable by segment and class modified in troubled debt restructuring
Number of Loans		6	3	12
Pre-Modification Recorded Investment		5,545	2,784	31,581
Recorded Investment		5,456	2,465	30,303
Commercial Real Estate
Information about mortgage loans receivable by segment and class modified in troubled debt restructuring
Number of Loans	2	2	3	3
Pre-Modification Recorded Investment	2,416	3,235	3,955	4,234
Recorded Investment	$ 2,359	$ 3,235	$ 3,698	$ 4,164