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Operating Leases - Narrative (Detail) | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2015 USD ($) ft² Location | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($)
Operating Leased Assets [Line Items] |  |  |
Area of operating lease | ft² | 42,400 |  |
Number of office space locations | Location | 2 |  |
Total future lease payments due | $ 5,933,000 |  |
Contractual reimbursement of lease payments expected over life of lease | $ 200,000 |  |
Operating lease expense excluding rent |  |  | $ 300,000
Lease Forecast |  |  |
Operating Leased Assets [Line Items] |  |  |
Operating lease expense excluding rent |  | $ 400,000 |

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- Definition Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 10 -Section 55 -Paragraph 40 -Subparagraph (Note 3) -URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717 + Details
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