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
Valuation Allowance for Doubtful Accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	$ 1,924	$ 2,078	$ 1,349
Additions Charged to Costs and Expenses	668	631	888
Additions Charged to Other Accounts	12	(62)
Deductions & Write-offs	(354)	(723)	(159)
Balance at End of Year	2,250	1,924	2,078
Valuation Allowance for Sales Returns [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	827	801	1,167
Additions Charged to Costs and Expenses	2,223	1,933	2,564
Additions Charged to Other Accounts		(36)
Deductions & Write-offs	(2,320)	(1,871)	(2,930)
Balance at End of Year	730	827	801
Valuation Allowance on Deferred Tax Asset [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	27,102	27,497	26,475
Additions Charged to Costs and Expenses			(44)
Additions Charged to Other Accounts			1,066
Deductions & Write-offs	(339)	(395)
Balance at End of Year	$ 26,763	$ 27,102	$ 27,497

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.

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 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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