Borrowings - Narrative (Details) - USD ($)		12 Months Ended
Oct. 27, 2015	Dec. 31, 2015
Borrowings
Borrowings subject to the bank's dominion		$ 0
Revolving credit facilities
Borrowings
Maximum borrowing capacity		60,000,000
Available borrowing base		53,600,000
Debt outstanding		$ 33,500,000
Weighted average interest rate (percent)		3.60%
Revolving credit facilities \| Wells Fargo Bank, N.A.
Borrowings
Maximum percent available for borrowings		25.00%
Maximum amount available for borrowing		$ 15,000,000
Minimum percent available for for borrowing		25.00%
Continuing compliance period requirement (days)		30 days
Maximum percent available for borrowing for lender dominion over U.S. cash and cash receipts for 5 consecutive days		30.00%
Maximum amount available for borrowing for lender dominion over U.S. cash and cash receipts for 5 consecutive days		$ 18,000,000
Maximum percent available for borrowing for lender dominion over U.S. cash and cash receipts		25.00%
Minimum amount available for borrowing for continuing compliance with 12-month fixed charge coverage ratio		$ 15,000,000
Continuing compliance period requirement for lender dominion over U.S. cash and cash receipts (days)		30 days
Minimum amount of excess availability for trigger date to occur	$ 10,000,000
Percent of commitments for trigger date to occur	16.67%
Minimum amount of excess availability for trigger date to occur, continuing compliance	$ 10,000,000
Percent of commitments for trigger date to occur, continuing compliance	16.67%
Continuing compliance period requirement for trigger date (days)	30 days
Revolving credit facilities \| Minimum
Borrowings
Unused line fee (percent)		0.375%
Revolving credit facilities \| Maximum
Borrowings
Unused line fee (percent)		0.50%
Revolving credit facilities \| LIBOR \| U.S.
Borrowings
Percentage points added to the reference rate		1.00%
Variable interest rate base		LIBOR
Revolving credit facilities \| LIBOR \| U.S. \| Minimum
Borrowings
Percentage points added to the reference rate		225.00%
Revolving credit facilities \| LIBOR \| U.S. \| Maximum
Borrowings
Percentage points added to the reference rate		275.00%
Revolving credit facilities \| LIBOR \| Foreign
Borrowings
Variable interest rate base		LIBOR
Revolving credit facilities \| LIBOR \| Foreign \| Minimum
Borrowings
Percentage points added to the reference rate		225.00%
Revolving credit facilities \| LIBOR \| Foreign \| Maximum
Borrowings
Percentage points added to the reference rate		275.00%
Revolving credit facilities \| Federal Funds Rate \| U.S.
Borrowings
Percentage points added to the reference rate		0.50%
Variable interest rate base		Federal Funds Rate
Revolving credit facilities \| Wells Fargo Prime rate \| U.S.
Borrowings
Variable interest rate base		prime rate
Revolving credit facilities \| Wells Fargo Prime rate \| U.S. \| Minimum
Borrowings
Percentage points added to the reference rate		125.00%
Revolving credit facilities \| Wells Fargo Prime rate \| U.S. \| Maximum
Borrowings
Percentage points added to the reference rate		175.00%

Debt Instrument, Covenant Compliance, Continuing Compliance Period Requirement for 12-month Fixed Charge Coverage Ratio

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Debt Instrument, Covenant Compliance, Continuing Compliance Period Requirement for Lender Dominion Over U.S. Cash and Cash Receipts

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Debt Instrument, Covenant Compliance, Continuing Compliance Period Requirement for Trigger Date

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Debt Instrument, Covenant Compliance, Maximum Amount Available for Borrowing for Initial 12-month Fixed Charge Coverage Ratio

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Debt Instrument, Covenant Compliance, Maximum Amount Available for Borrowing for Lender Dominion Over U.S. Cash and Cash Receipts for 5 Consecutive Days

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Debt Instrument, Covenant Compliance, Maximum Percent Available for Borrowing for Initial 12-month Fixed Charge Coverage Ratio

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Debt Instrument, Covenant Compliance, Maximum Percent Available for Borrowing for Lender Dominion Over U.S. Cash and Cash Receipts

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Debt Instrument, Covenant Compliance, Maximum Percent Available for Borrowing for Lender Dominion Over U.S. Cash and Cash Receipts for 5 Consecutive Days

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Debt Instrument, Covenant Compliance, Minimum Amount Available for Borrowing for Continuing Compliance with 12-month Fixed Charge Coverage Ratio

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Debt Instrument, Covenant Compliance, Minimum Amount of Excess Availability for Trigger Date to Occur

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Debt Instrument, Covenant Compliance, Minimum Amount of Excess Availability for Trigger Date to Occur, Continuing Compliance

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Debt Instrument, Covenant Compliance, Minimum Percent Available for Borrowing for Continuing Compliance with 12-month Fixed Charge Coverage Ratio

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- Definition

Debt Instrument, Covenant Compliance, Percent of Commitments for Trigger Date to Occur

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Debt Instrument, Covenant Compliance, Percent of Commitments for Trigger Date to Occur, Continuing Compliance

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- Definition

Obligation related to long-term debt (excluding convertible debt) and capital leases, the portion which is due in one year or less in the future and subject to the bank's dominion.

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- Definition

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

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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.

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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.

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Weighted average interest rate of debt outstanding.

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any 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
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Fair value of the amount outstanding under the credit facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13433-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13476-108611

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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.

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

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