Fair Value Measurements - Additional Information (Detail) - USD ($) |
Mar. 31, 2016 |
Dec. 31, 2015 |
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| Fair Value Measurements Disclosure [Line Items] | ||
| The fair value investments reclassification of assets between level 1 and level 2 | $ 0 | $ 0 |
| The fair value of Senior Notes, based on quoted market prices | 457,500,000 | 403,100,000 |
| Fair Value, Inputs, Level 3 [Member] | ||
| Fair Value Measurements Disclosure [Line Items] | ||
| Level 3 investments | $ 0 | $ 0 |
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- Definition Fair Value Measurements Disclosure [Line Items] No definition available.
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- Definition Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Fair value portion of notes payable. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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