Principal Payment For Term Loan (Detail) - Senior Credit Facility - USD ($)	3 Months Ended	12 Months Ended
Dec. 31, 2016	Dec. 31, 2016
Line of Credit Facility [Line Items]
Payment amount per quarter	$ 0
Term Loan Facility \| Debt Instrument, Redemption, Period One
Line of Credit Facility [Line Items]
Principal payments, beginning from		Dec. 31, 2016
Principal payments, until		Sep. 30, 2017
Payment amount per quarter		$ 3,750,000
Term Loan Facility \| Debt Instrument, Redemption, Period Two
Line of Credit Facility [Line Items]
Principal payments, beginning from		Oct. 31, 2017
Principal payments, until		Sep. 30, 2018
Payment amount per quarter		$ 5,625,000
Term Loan Facility \| Debt Instrument, Redemption, Period Three
Line of Credit Facility [Line Items]
Principal payments, beginning from		Oct. 31, 2018
Principal payments, until		Jun. 30, 2021
Payment amount per quarter		$ 7,500,000

Latest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Earliest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

+ References

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+ References

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Amount of the required periodic payment applied to principal.

+ References

Reference 1: 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(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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