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

+ 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

+ Details

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- Definition

+ References

+ Details

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- Definition

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.

+ References

+ Details

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- Details

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Schedule of valuation and qualifying accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Allowance for doubtful accounts receivable
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 20	$ 20	$ 20
Charged to Cost and Expense
Charged to Other Accounts
Deductions Charged to Reserves
Balance at End of Period	20	20	20
Inventory reserves
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period
Charged to Cost and Expense
Charged to Other Accounts
Deductions Charged to Reserves
Balance at End of Period
Warranty reserves
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period
Charged to Cost and Expense
Charged to Other Accounts
Deductions Charged to Reserves
Balance at End of Period
Deferred tax asset valuation allowance
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period
Charged to Cost and Expense
Charged to Other Accounts
Deductions Charged to Reserves
Balance at End of Period