Commitments and Contingencies - Future Minimum Commitments under Non-Cancelable Operating Leases with Initial or Remaining Terms of One Year or More (Detail) $ in Thousands	Dec. 31, 2017 USD ($)
Leases [Abstract]
2018	$ 3,278
2019	2,499
2020	1,847
2021	1,488
2022	757
Thereafter	798
Future minimum lease payments	$ 10,667

No definition available.

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- Definition

Future minimum rental payments in aggregate as of the balance sheet date under operating leases.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84164653&loc=d3e41551-112718

+ Details

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- Definition

Future rental payments receivable within one year of the balance sheet date under an operating lease.

+ References

+ Details

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- Definition

Future rental payments receivable within the fifth year from the balance sheet date under an operating lease.

+ References

+ Details

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- Definition

Future rental payments receivable within the fourth year from the balance sheet date under an operating lease.

+ References

+ Details

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- Definition

Future rental payments receivable within the third year from the balance sheet date under an operating lease.

+ References

+ Details

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- Definition

Future rental payments receivable within the second year from the balance sheet date under an operating lease.

+ References

+ Details

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- Definition

Future minimum lease payments receivable under operating leases for periods greater than five years following the balance sheet date.

+ References

+ Details

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