Loans Receivable and Allowance for Loan Losses (Details 10) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Average recorded investment, interest income recognized and cash basis interest income related to impaired mortgage loans by segment and class
Average Recorded Investment	$ 399,956	$ 358,036	$ 404,103	$ 339,201
Interest Income Recognized	2,809	2,241	5,456	4,611
Cash Basis Interest Income	3,002	2,355	5,865	5,134
Residential \| Full documentation interest-only loans
Average recorded investment, interest income recognized and cash basis interest income related to impaired mortgage loans by segment and class
Average Recorded Investment, Loans with an allowance recorded	103,076	10,378	102,934	10,448
Average Recorded Investment, Loans without an allowance recorded	19,119	83,978	19,244	81,249
Interest Income Recognized, Loans with an allowance recorded	608	81	1,157	174
Interest Income Recognized, Loans without an allowance recorded	96	356	166	660
Cash Basis Interest Income, Loans with an allowance recorded	630	85	1,262	179
Cash Basis Interest Income, Loans without an allowance recorded	91	350	170	700
Residential \| Full documentation amortizing loans
Average recorded investment, interest income recognized and cash basis interest income related to impaired mortgage loans by segment and class
Average Recorded Investment, Loans with an allowance recorded	27,316	4,104	27,615	4,031
Average Recorded Investment, Loans without an allowance recorded	6,153	18,085	5,861	17,748
Interest Income Recognized, Loans with an allowance recorded	171	39	289	81
Interest Income Recognized, Loans without an allowance recorded	17	59	67	107
Cash Basis Interest Income, Loans with an allowance recorded	173	38	305	81
Cash Basis Interest Income, Loans without an allowance recorded	15	55	65	112
Residential \| Reduced documentation interest-only loans
Average recorded investment, interest income recognized and cash basis interest income related to impaired mortgage loans by segment and class
Average Recorded Investment, Loans with an allowance recorded	150,542	10,982	149,207	11,226
Average Recorded Investment, Loans without an allowance recorded		118,551	2,781	115,561
Interest Income Recognized, Loans with an allowance recorded	992	114	1,897	235
Interest Income Recognized, Loans without an allowance recorded		520		987
Cash Basis Interest Income, Loans with an allowance recorded	1,018	115	2,042	241
Cash Basis Interest Income, Loans without an allowance recorded		509		1,064
Residential \| Reduced documentation amortizing loans
Average recorded investment, interest income recognized and cash basis interest income related to impaired mortgage loans by segment and class
Average Recorded Investment, Loans with an allowance recorded	25,243	2,006	25,870	1,930
Average Recorded Investment, Loans without an allowance recorded		17,889		17,012
Interest Income Recognized, Loans with an allowance recorded	209	19	297	42
Interest Income Recognized, Loans without an allowance recorded		102		202
Cash Basis Interest Income, Loans with an allowance recorded	210	19	322	41
Cash Basis Interest Income, Loans without an allowance recorded		105		232
Multi-Family
Average recorded investment, interest income recognized and cash basis interest income related to impaired mortgage loans by segment and class
Average Recorded Investment, Loans with an allowance recorded	16,380	63,795	17,488	54,621
Average Recorded Investment, Loans without an allowance recorded	32,404	9,543	33,740	7,194
Interest Income Recognized, Loans with an allowance recorded	180	578	373	1,227
Interest Income Recognized, Loans without an allowance recorded	346	166	745	366
Cash Basis Interest Income, Loans with an allowance recorded	195	674	380	1,552
Cash Basis Interest Income, Loans without an allowance recorded	389	156	796	356
Commercial Real Estate
Average recorded investment, interest income recognized and cash basis interest income related to impaired mortgage loans by segment and class
Average Recorded Investment, Loans with an allowance recorded	8,586	12,744	9,335	14,194
Average Recorded Investment, Loans without an allowance recorded	11,137	5,981	10,028	3,987
Interest Income Recognized, Loans with an allowance recorded	139	76	240	261
Interest Income Recognized, Loans without an allowance recorded	51	131	225	269
Cash Basis Interest Income, Loans with an allowance recorded	147	118	264	314
Cash Basis Interest Income, Loans without an allowance recorded	$ 134	$ 131	$ 259	$ 262

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5258-111524

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