v3.8.0.1

Restructuring Charges - Narrative (Details) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2018 USD ($) | Sep. 30, 2017 USD ($) ft² | Apr. 01, 2017 USD ($)
Capital Leased Assets [Line Items] |  |  |
Lease obligation |  | $ 3,100 |
Deferred rent liability | $ 462 | $ 2,600 | $ 0
Impairment of leasehold | 500 |  |
Additional restructuring charges | $ 500 |  |
Massachusetts |  |  |
Capital Leased Assets [Line Items] |  |  |
Area of real estate property | ft² |  | 108,743 |
Massachusetts | Property Subject to Operating Lease |  |  |
Capital Leased Assets [Line Items] |  |  |
Area of real estate property | ft² |  | 25,812 |

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- Definition Amount of capital lease obligation due within one year or the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84164817&loc=d3e45280-112737 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(19)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=84164758&loc=d3e45023-112735 + Details
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- Definition The adjustment to reduce the value of existing agreements that specify the lessee's rights to use the leased property. This expense is charged when the estimates of future profits generated by the leased property are reduced. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2420-110228 + Details
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