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Schedule II - Valuation and Qualifying Accounts (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Allowance for Doubtful Accounts [Member] |  |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance, beginning of year | $ 1,719 | $ 2,239 | $ 2,703
Provision | 49 | 32 | 7
Write-offs, recoveries and discounts allowed | (29) | (497) | (275)
Other | 218 | (55) | (196)
Balance, end of year | 1,957 | 1,719 | 2,239
Allowance for Sales Discounts and Deductions [Member] |  |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance, beginning of year | 1,462 | 1,593 | 1,809
Provision | 4,610 | 4,283 | 3,856
Write-offs, recoveries and discounts allowed | (4,697) | (4,368) | (3,649)
Other | 68 | (46) | (423)
Balance, end of year | $ 1,443 | $ 1,462 | $ 1,593

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- Definition Valuation allowances and reserves write offs recoveries and discounts allowed. + References No definition available. + Details
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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 + Details
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- Definition 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 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 + Details
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