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Operating Leases - Narrative (Detail) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2016 ft² Location | Dec. 31, 2015 USD ($)
Leases [Abstract] |  |
Area of operating lease | ft² | 42,400 |
Number of office space locations | Location | 2 |
Operating lease expense excluding rent | $ |  | $ 0.4

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- Definition Lessee Leasing Agreements, Operating Leases, Area under Lease + References No definition available. + Details
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- Definition Operating Lease Expense Excluding Rent + References No definition available. + Details
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Balance Type: | debit
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- References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Definition The number of units (items of property) under operating lease arrangements. + References No definition available. + Details
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