Fair Values - Additional Information (Detail) $ in Millions	12 Months Ended
Dec. 31, 2014 USD ($) SecurityLoan	Jun. 30, 2015 USD ($) SecurityLoan
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Book value of securities		$ 11.0
Loans receivable	$ 19.0
Number of loans \| SecurityLoan		0
Aggregate book value of equity investments and other receivables		$ 2.9
Hotel [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of loans \| SecurityLoan	1
Discount rate	7.00%
Fair value of a 100 bp discount rate increase	0.30%
Office [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of loans \| SecurityLoan	1
Discount rate	15.00%
Fair value of a 100 bp discount rate increase	1.10%

The percent of book value sensitivity to a 100 bps discount rate increase used as an input to measure fair value.

No definition available.

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- Definition

Equity Investments and Other Receivables Carrying Value

+ References

No definition available.

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- Definition

Loans Receivable Number Of Loans

+ References

No definition available.

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- Definition

Investments in notes or bonds that are collateralized by a specific group of underlying assets owned by the issuer of the notes or bonds which are short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Glossary Loan

-URI http://asc.fasb.org/extlink&oid=6517073

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