Commercial Real Estate Loan Types (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Commercial Mortgages
Apartment/ Multi-family	$ 728.7	$ 616.2
Office	735.5	686.0
Retail	854.1	768.0
Industrial/ Warehouse	323.7	318.6
Other	125.7	110.6
Total Commercial Mortgages	2,767.7	2,499.4
Construction, Acquisition and Development Loans	256.8	254.2
Single Family Investment	121.3	110.0
Other Commercial Real Estate Related	187.5	92.2
Total Commercial Real Estate Loans	$ 3,333.3	$ 2,955.8

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Loans Receivable Commercial Construction Acquisition And Development

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Loans Receivable, Commercial Real Estate, Commercial Mortgage, Apartments And Multi Family

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Loans Receivable, Commercial Real Estate, Commercial Mortgage, Industrial And Warehouse

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Loans Receivable, Commercial Real Estate, Commercial Mortgage, Office

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Loans Receivable, Commercial Real Estate, Commercial Mortgage, Other

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Loans Receivable, Commercial Real Estate, Commercial Mortgage, Retail

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Loans Receivable Commercial Real Estate Other

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Loans receivable - commercial real estate - single family investment

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Amount before allowance of mortgage loans on existing land or building. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

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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

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-Topic 942

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-Name Regulation S-X (SX)

-Number 210

-Section 03

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Amount before allowance of commercial loans issued to businesses to acquire, develop, construct, improve, or refinance land or building. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

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

-Publisher FASB

-Name Accounting Standards Codification

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-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5066-111524

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-Publisher FASB

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-Topic 944

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-Subparagraph (SX 210.7-03.1(c))

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