Schedule II - Valuation and Qualifying Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Allowance for doubtful receivables
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning of Period	$ 1,251	$ 709	$ 480
Charges to Costs and Expenses	941	855	384
Charges (Deductions) to Other Accounts	(123)	(53)	(39)
Deductions	(640)	(260)	(116)
End of Period	1,429	1,251	709
Tax valuation allowances
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning of Period	4,307	3,727	3,315
Charges to Costs and Expenses	762	1,615	1,120
Charges (Deductions) to Other Accounts	(140)	(272)	193
Deductions	(26)	(763)	(901)
End of Period	$ 4,903	$ 4,307	$ 3,727

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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Amount of increase in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from charges to costs and expenses.

+ References

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- Definition

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Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

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