Investments - Additional Information (Detail) - USD ($) |
3 Months Ended | 9 Months Ended | |
|---|---|---|---|
Sep. 30, 2014 |
Sep. 30, 2015 |
Sep. 30, 2014 |
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| Schedule of Equity Method Investments [Line Items] | |||
| Gain on sale of investment | $ 0 | $ 0 | $ 1,480,000 |
| Class A Common Stock | |||
| Schedule of Equity Method Investments [Line Items] | |||
| Gain on sale of investment | 500,000 | ||
| Real Goods Solar | Class A Common Stock | |||
| Schedule of Equity Method Investments [Line Items] | |||
| Gain on sale of investment | $ 1,000,000 | ||
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- Definition Amount of gain (loss) on sale or disposal of an equity method investment. No definition available.
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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. No definition available.
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