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	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Total impaired loans
Average Recorded Investment	$ 229,633	$ 245,047	$ 232,262	$ 246,176
Interest Income Recognized	1,921	2,317	3,867	4,525
Cash Basis Interest Income	1,955	2,318	3,933	4,598
Consumer and Other Loans \| Home equity lines of credit
With an allowance recorded:
Average Recorded Investment	4,488	6,179	4,648	5,837
Interest Income Recognized	11	20	21	32
Cash Basis Interest Income	9	22	20	39
Mortgage Loans \| Residential \| Full documentation interest-only
With an allowance recorded:
Average Recorded Investment	26,744	42,150	28,040	43,544
Interest Income Recognized	154	295	290	608
Cash Basis Interest Income	154	291	302	614
Mortgage Loans \| Residential \| Full documentation amortizing
With an allowance recorded:
Average Recorded Investment	70,988	50,619	68,400	47,077
Interest Income Recognized	524	380	1,070	798
Cash Basis Interest Income	534	391	1,077	816
Mortgage Loans \| Residential \| Reduced documentation interest-only
With an allowance recorded:
Average Recorded Investment	35,843	74,210	39,409	75,126
Interest Income Recognized	300	840	622	1,528
Cash Basis Interest Income	300	821	615	1,527
Mortgage Loans \| Residential \| Reduced documentation amortizing
With an allowance recorded:
Average Recorded Investment	64,400	21,888	60,440	20,631
Interest Income Recognized	594	203	1,156	392
Cash Basis Interest Income	597	207	1,178	401
Mortgage Loans \| Multi-Family
With an allowance recorded:
Average Recorded Investment	5,232	14,731	6,138	19,190
Interest Income Recognized	56	75	120	159
Cash Basis Interest Income	68	81	138	183
Without an allowance recorded:
Average Recorded Investment	9,385	17,014	11,821	16,177
Interest Income Recognized	113	138	243	534
Cash Basis Interest Income	121	138	254	534
Mortgage Loans \| Commercial Real Estate
With an allowance recorded:
Average Recorded Investment	686	13,751	2,698	15,591
Interest Income Recognized	5	100	11	197
Cash Basis Interest Income	5	101	12	209
Without an allowance recorded:
Average Recorded Investment	11,867	4,505	10,668	3,003
Interest Income Recognized	164	266	334	277
Cash Basis Interest Income	$ 167	$ 266	$ 337	$ 275

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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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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