Debt and Leases - Debt (Details) - USD ($)	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Debt:
Long-term Debt	$ 9,750,000	$ 13,464,000
Current portion of long-term debt	(3,000,000)	(3,714,000)
Long-term debt	6,750,000	9,750,000
Loans payable \| Capex loan
Debt:
Long-term Debt	$ 0	$ 714,000
Stated interest rate	0.00%	2.04%
Repayment term	7 years
Debt instrument, face amount	$ 12,000,000
Debt Instrument, Description of Variable Rate Basis	30 day LIBOR
Basis spread on variable rate	1.60%
Loans payable \| Term Loan [Member]
Debt:
Long-term Debt	$ 9,750,000	$ 12,750,000
Stated interest rate	2.55%	2.24%
Repayment term	5 years
Debt instrument, face amount	$ 15,500,000
Debt Instrument, Description of Variable Rate Basis	30 day LIBOR
Basis spread on variable rate	1.80%
Loans payable \| Mexican Loan [Member]
Debt:
Debt instrument, face amount	$ 8,000,000
Debt Instrument, Description of Variable Rate Basis		LIBOR
Line of credit
Debt:
Percent of subsidiary stock not security for financing	65.00%
Debt Instrument, Description of Variable Rate Basis	daily LIBOR
Line of credit \| Revolving line of credit
Debt:
Long-term Debt	$ 0	$ 0
Line of credit facility, maximum borrowing capacity	$ 18,000,000
Basis spread on variable rate	1.60%

Long-term Debt, Maturities, Repayment Term

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- Definition

Percent of Subsidiary Stock Not Security for Financing

+ References

No definition available.

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- Definition

Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19,20)
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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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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

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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