Long‑Term Debt - Narrative (Details)	1 Months Ended
Mar. 31, 2018 USD ($) installment	Dec. 31, 2017 USD ($)
Debt Instrument [Line Items]
Outstanding balance	$ 17,449,000	$ 17,471,000
2014 Pacific Western Bank, Term and Revolving Loans
Debt Instrument [Line Items]
Debt instrument, face amount	25,000,000.0
Outstanding balance	17,200,000	17,200,000
Term Loan \| 2014 Pacific Western Bank, Term and Revolving Loans
Debt Instrument [Line Items]
Debt instrument, face amount	$ 15,000,000.0
Number of monthly installments \| installment	36
Outstanding balance	$ 13,500,000	13,500,000
Revolving Credit Facility \| Line of Credit \| 2014 Pacific Western Bank, Term and Revolving Loans
Debt Instrument [Line Items]
Outstanding balance	3,700,000	$ 3,700,000
Borrowing Capacity less Unpaid Principal Amount \| Revolving Credit Facility \| Line of Credit \| 2014 Pacific Western Bank, Term and Revolving Loans
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 25,000,000.0
Borrowing Capacity as a Percentage of Accounts Receivable \| Revolving Credit Facility \| Line of Credit \| 2014 Pacific Western Bank, Term and Revolving Loans
Debt Instrument [Line Items]
Borrowing base as a percentage of eligible accounts receivable	85.00%
Borrowing base, basis spread, amount	$ 5,500,000.0
Borrowing base, basis spread, percentage of eligible inventory	35.00%
Prime Rate \| Term Loan \| 2014 Pacific Western Bank, Term and Revolving Loans
Debt Instrument [Line Items]
Basis on variable rate	0.50%
Variable rate floor	5.00%

Debt Instrument, Payment Terms, Number Of Installments

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- Definition

Debt Instrument, Variable Rate, Floor

+ References

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- Definition

Line Of Credit Facility, Borrowing Capacity, Basis Spread On Variable Capacity, Amount

+ References

No definition available.

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- Definition

Line Of Credit Facility, Borrowing Capacity, Basis Spread On Variable Capacity, Percentage Of Inventory

+ References

No definition available.

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- Definition

Line Of Credit Facility, Borrowing Capacity, Percentage Of Accounts Receivable

+ References

No definition available.

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- Definition

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

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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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

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
-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

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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