Income Taxes - Deferred Tax Assets and Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Net current deferred assets and (liabilities) relating to:
Valuation reserves	$ 304	$ 164
Warranty accrual	2,901	2,287
Other accruals	1,420	1,996
Other, net	154	46
Total	4,779	4,493
Net long-term deferred assets and (liabilities) relating to:
Depreciation	(14,843)	(16,659)
Share-based compensation	692	653
Other, net	(273)	274
Total	$ (14,424)	$ (15,732)

Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences expected to be realized or consumed after one year (or the normal operating cycle, if longer).

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 45

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=21917399&loc=d3e31917-109318

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 45

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=21917399&loc=d3e31931-109318

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant