Related Party Transactions - Additional Information (Detail) - USD ($)	6 Months Ended
Jun. 30, 2015	Dec. 31, 2014
Related Party Transaction [Line Items]
Loan to related party	$ 9,500,000	$ 9,500,000
Equity Method Investee [Member]
Related Party Transaction [Line Items]
Loan to related party	$ 9,500,000
Ownership percentage	30.00%
Carrying value of equity investment recoverable	$ 2,000,000
Provision for loans	0
Equity Method Investee [Member] \| Loan [Member]
Related Party Transaction [Line Items]
Installment payment defaulted	$ 1,600,000

Amount of outstanding long-term debt or borrowing associated with any securities or credit agreement for which there has been a default in principal, interest, sinking fund, or redemption provisions, or any breach of covenant that existed at the end of the period and subsequently has not been cured.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(c))

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The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

+ References

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

-Publisher FASB

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-Publisher SEC

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

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Amount of expense related to estimated loss from loan and lease transactions.

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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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