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Operating Leases - Narrative (Detail) (USD $) | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2014 sqft Location | Dec. 31, 2013 | Dec. 31, 2015 Lease Forecast sqft | Dec. 31, 2014 Lease Forecast
Operating Leased Assets [Line Items] |  |  |  |
Area of operating lease | 36,800 |  | 42,200 |
Operating Lease Expense Excluding Rent |  | $ 245,000 |  | $ 334,000
Number of office space locations | 3 |  |  |
Total future lease payments due | 6,420,000 |  |  |
Contractual Reimbursement of Lease Payments Expected Over Life of Lease | $ 294,000 |  |  |

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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 20 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717 Reference 2: 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 + Details
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