Loans Receivable and Allowance for Loan Losses (Average Recorded Investment, Interest Income Recognized and Cash Basis Interest Income on Impaired Loans) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Total impaired loans
Average Recorded Investment	$ 233,663	$ 247,622
Interest Income Recognized	1,995	2,324
Cash Basis Interest Income	1,993	2,363
Consumer and Other Loans \| Home Equity and Other Consumer
With an allowance recorded:
Average Recorded Investment	4,753	5,829
Interest Income Recognized	5	6
Cash Basis Interest Income	9	16
Mortgage Loans \| Residential \| Full documentation interest-only
With an allowance recorded:
Average Recorded Investment	29,462	44,759
Interest Income Recognized	189	349
Cash Basis Interest Income	186	353
Mortgage Loans \| Residential \| Full documentation amortizing
With an allowance recorded:
Average Recorded Investment	64,858	43,989
Interest Income Recognized	494	395
Cash Basis Interest Income	478	386
Mortgage Loans \| Residential \| Reduced documentation interest-only
With an allowance recorded:
Average Recorded Investment	43,118	76,396
Interest Income Recognized	391	730
Cash Basis Interest Income	385	737
Mortgage Loans \| Residential \| Reduced documentation amortizing
With an allowance recorded:
Average Recorded Investment	57,203	18,948
Interest Income Recognized	525	162
Cash Basis Interest Income	529	162
Mortgage Loans \| Multi-Family
With an allowance recorded:
Average Recorded Investment	6,813	24,542
Interest Income Recognized	67	260
Cash Basis Interest Income	79	268
Without an allowance recorded:
Average Recorded Investment	13,375	13,759
Interest Income Recognized	152	154
Cash Basis Interest Income	149	155
Mortgage Loans \| Commercial Real Estate
With an allowance recorded:
Average Recorded Investment	3,875	19,400
Interest Income Recognized	6	268
Cash Basis Interest Income	7	286
Without an allowance recorded:
Average Recorded Investment	10,206	0
Interest Income Recognized	166	0
Cash Basis Interest Income	$ 171	$ 0

Impaired Financing Receivable, Total [Abstract]

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Impaired Financing Receivable, with No Related Allowance [Abstract]

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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=49124121&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=49124121&loc=d3e5258-111524

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Amount of average investment of impaired financing receivables for which there is no 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 17
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5258-111524

Reference 2: 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=49124121&loc=d3e5212-111524

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