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Borrowings (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Schedule Of Short Term And Long Term Debt [Line Items]
FHLB advances	$ 797.3
Unencumbered securities	537.4
Multifamily loans held as collateral	308.7
Repurchase Agreements
Schedule Of Short Term And Long Term Debt [Line Items]
Weighted average interest rate	2.70%	3.02%
Interest rate	2.92%
Mortgage Backed Securities [Member] | Repurchase Agreements
Schedule Of Short Term And Long Term Debt [Line Items]
Mortgage-backed securities amortized cost	192.7	242.4
Mortgage-backed securities held for sale fair value	$ 197.9	$ 254.2
Maturity 30 to 90 Days [Member] | Repurchase Agreements
Schedule Of Short Term And Long Term Debt [Line Items]
Number of repurchase agreements	1
Maturity over 90 days [Member] | Repurchase Agreements
Schedule Of Short Term And Long Term Debt [Line Items]
Maturity period	90 days	90 days

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- Definition

Additional Funding Federal Home Loan Bank Advances Long Term

+ References

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Multifamily Loans Held As Collateral by Federal Home Loan Bank.

+ References

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- Definition

Number Of Repurchase Agreements

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- Definition

Unencumbered Securities

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X

- Definition

Interest rate stated in the contractual debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Reflects the calculation as of the balance sheet date of the average interest rate weighted by the amount of debt outstanding by type or by instrument at that time.

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- Definition

Amount of investments in debt securities categorized as held-to-maturity valued at amortized cost, excludes other than temporary impairment (OTTI).

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents securitized, pay-through debt securities collateralized by real estate mortgage loans (mortgages) as of the balance sheet date which have been categorized as held-to-maturity. The held-to-maturity category is for those securities that the Entity has the positive intent and ability to hold until maturity.

+ References

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

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Paragraph 15

-IssueDate 2006-05-01

-Chapter 7

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Mortgage-Backed Securities

-URI http://asc.fasb.org/extlink&oid=6517959

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