Loans Receivable and Allowance for Loan Losses (Details 10) (Mortgage Loans (Gross), USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012 item	Dec. 31, 2011 item
Information about loans receivable by segment and class modified in troubled debt restructuring
Number of Loans	93	65
Pre-Modification Recorded Investment	$ 62,994	$ 34,350
Recorded Investment	56,941	32,965
Residential Mortgage Loans | Full Documentation Interest-only Loans
Information about loans receivable by segment and class modified in troubled debt restructuring
Number of Loans	20	14
Pre-Modification Recorded Investment	4,390	5,750
Recorded Investment	4,355	5,698
Residential Mortgage Loans | Full Documentation Amortizing Loans
Information about loans receivable by segment and class modified in troubled debt restructuring
Number of Loans	11	2
Pre-Modification Recorded Investment	3,319	438
Recorded Investment	3,291	389
Residential Mortgage Loans | Reduced Documentation Interest-only Loans
Information about loans receivable by segment and class modified in troubled debt restructuring
Number of Loans	29	28
Pre-Modification Recorded Investment	11,141	12,116
Recorded Investment	11,125	11,941
Residential Mortgage Loans | Reduced Documentation Amortizing Loans
Information about loans receivable by segment and class modified in troubled debt restructuring
Number of Loans	14	6
Pre-Modification Recorded Investment	3,984	1,204
Recorded Investment	3,860	1,176
Multi-Family
Information about loans receivable by segment and class modified in troubled debt restructuring
Number of Loans	16	11
Pre-Modification Recorded Investment	36,262	7,666
Recorded Investment	32,005	7,140
Commercial Real Estate
Information about loans receivable by segment and class modified in troubled debt restructuring
Number of Loans	3	4
Pre-Modification Recorded Investment	3,898	7,176
Recorded Investment	$ 2,305	$ 6,621