Debt and Other Contractual Obligations - Summary of Future Contractual Obligations (Detail) $ in Thousands	Mar. 31, 2018 USD ($)
Debt Disclosure [Abstract]
Operating lease obligations, Total	$ 407
Operating lease obligations, Remainder of 2018	333
Operating lease obligations, 2019	74
Loan principal repayments, Total	2,453
Loan principal repayments, Remainder of 2018	193
Loan principal repayments, 2019	251
Loan principal repayments, 2020	258
Loan principal repayments, 2021	265
Loan principal repayments, 2022	273
Loan principal repayments, Thereafter	1,213
Capital lease obligations, Total	1,351
Capital lease obligations, Remainder of 2018	243
Capital lease obligations, 2019	337
Capital lease obligations, 2020	351
Capital lease obligations, 2021	365
Capital lease obligations, 2022	55
Minimum purchase obligation, Total	5,062
Minimum purchase obligation, Remainder of 2018	3,203
Minimum purchase obligation, 2019	1,859
Total	9,273
Remainder of 2018	3,972
2019	2,521
2020	609
2021	630
2022	328
Thereafter	$ 1,213

Amount of minimum lease payments for capital leases.

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

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

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Minimum amount of purchase arrangement maturing in the second fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

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