Notes Payable (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2017	Dec. 31, 2016
Notes payable
Total notes payable	$ 566	$ 451
Less: current maturities	(212)	(169)
Notes payable, net of current portion	354	282
Notes payable to insurance finance company
Notes payable
Total notes payable		11
Debt Instrument, Periodic Payment		$ 11
Debt Instrument, Interest Rate, Stated Percentage		4.40%
Notes payable to vehicle companies
Notes payable
Total notes payable	566	$ 440
Minimum \| Notes payable to vehicle companies
Notes payable
Debt Instrument, Periodic Payment	$ 200
Debt Instrument, Interest Rate, Stated Percentage	0.00%
Maximum \| Notes payable to vehicle companies
Notes payable
Debt Instrument, Periodic Payment	$ 700
Debt Instrument, Interest Rate, Stated Percentage	6.60%

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

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+ References

No definition available.

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Amount of the required periodic payments including both interest and principal payments.

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Carrying value as of the balance sheet date of notes payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

+ References

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- Definition

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond 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(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: 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 3: 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

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Sum of the carrying values as of the balance sheet date of the portions of long-term notes payable due within one year or the operating cycle if longer.

+ References

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