Long-Term Debt - Narrative (Details) - USD ($)	1 Months Ended
Sep. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Outstanding balance	$ 16,225,000	$ 17,471,000
Pacific Western Bank, Second Amended and Restated Loan and Security Agreement \| Revolving Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity	40,000,000.0
Pacific Western Bank, Term and Revolving Loans \| Term Loan
Debt Instrument [Line Items]
Outstanding balance	0	13,500,000
Pacific Western Bank, Term and Revolving Loans \| Revolving Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Outstanding balance	$ 16,100,000	$ 3,700,000
Minimum \| Pacific Western Bank, Second Amended and Restated Loan and Security Agreement \| Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Basis on variable rate	1.35%
Minimum \| Pacific Western Bank, Second Amended and Restated Loan and Security Agreement \| Revolving Credit Facility \| Prime Rate
Debt Instrument [Line Items]
Basis on variable rate	0.50%
Maximum \| Pacific Western Bank, Second Amended and Restated Loan and Security Agreement \| Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Basis on variable rate	2.25%
Maximum \| Pacific Western Bank, Second Amended and Restated Loan and Security Agreement \| Revolving Credit Facility \| Prime Rate
Debt Instrument [Line Items]
Basis on variable rate	1.40%

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

No definition available.

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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.

+ Details

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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

+ Details

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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

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

Reference 3: 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(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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