Schedule II -Valuation and Qualifying Accounts (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reserve for Uncollectible Accounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 1,354	$ 1,131	$ 1,240
Charged to Costs and Expenses	(60)	286	63
Deductions	(141)	(77)	(184)
Other	(58)	14	12
Balance at End of Period	1,095	1,354	1,131
Reserve for Inventory Obsolescence [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	4,893	3,414	4,359
Charged to Costs and Expenses	3,535	2,368	949
Deductions	(1,989)	(1,009)	(1,924)
Other	(469)	120	30
Balance at End of Period	5,970	4,893	3,414
Deferred Tax Valuation Allowance [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	1,758	1,489	3,400
Charged to Costs and Expenses	725	642	546
Deductions	0	(373)	(2,457)
Balance at End of Period	$ 2,483	$ 1,758	$ 1,489

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Total of the adjustments 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

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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.

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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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