Amount of revenue earned from products sold or services provided under the terms of a contract, including, but not limited to, government contracts and construction contracts, classified as other.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(a))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

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- Details

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- Details

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Major Customers (Details) - USD ($)	3 Months Ended												12 Months Ended
Major Customers (Details) - USD ($)	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Major customers:
Total product sales	$ 33,465,000	$ 33,816,000	$ 36,813,000	$ 42,530,000	$ 43,492,000	$ 44,243,000	$ 53,514,000	$ 47,854,000	$ 42,592,000	$ 43,171,000	$ 43,317,000	$ 40,664,000	$ 146,624,000	$ 189,103,000	$ 169,744,000
Total tooling sales	15,607,000	7,520,000	2,193,000	2,938,000	3,072,000	3,806,000	1,342,000	1,745,000	1,822,000	420,000	2,807,000	411,000	28,258,000	9,965,000	5,460,000
Total net sales	$ 49,072,000	$ 41,336,000	$ 39,006,000	$ 45,468,000	$ 46,564,000	$ 48,049,000	$ 54,856,000	$ 49,599,000	$ 44,414,000	$ 43,591,000	$ 46,124,000	$ 41,075,000	174,882,000	199,068,000	175,204,000
Product sales
Major customers:
Total net sales													146,624,000	189,103,000	169,744,000
Tooling sales
Major customers:
Total net sales													28,258,000	9,965,000	5,460,000
Navistar
Major customers:
Total net sales													41,750,000	56,415,000	51,330,000
Navistar \| Product sales
Major customers:
Total net sales													39,756,000	50,169,000	51,254,000
Navistar \| Tooling sales
Major customers:
Total net sales													1,994,000	6,246,000	76,000
Volvo [Member]
Major customers:
Total net sales													49,970,000	55,125,000	48,859,000
Volvo [Member] \| Product sales
Major customers:
Total net sales													29,520,000	53,525,000	46,340,000
Volvo [Member] \| Tooling sales
Major customers:
Total net sales													20,450,000	1,600,000	2,519,000
Paccar
Major customers:
Total net sales													27,716,000	34,430,000	36,128,000
Paccar \| Product sales
Major customers:
Total net sales													24,235,000	33,452,000	35,602,000
Paccar \| Tooling sales
Major customers:
Total net sales													3,481,000	978,000	526,000
Yamaha [Member]
Major customers:
Total net sales													16,205,000	16,766,000	16,911,000
Yamaha [Member] \| Product sales
Major customers:
Total net sales													16,205,000	16,766,000	16,911,000
Yamaha [Member] \| Tooling sales
Major customers:
Total net sales													0	0	0
Other customers
Major customers:
Total net sales													39,241,000	36,332,000	21,976,000
Other customers \| Product sales
Major customers:
Total net sales													36,908,000	35,191,000	19,637,000
Other customers \| Tooling sales
Major customers:
Total net sales													$ 2,333,000	$ 1,141,000	$ 2,339,000