Commitments and Contingencies (Details)					1 Months Ended			12 Months Ended		13 Months Ended
	Jan. 22, 2019 USD ($)	Oct. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2018 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2014 diesel_engine	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($) letter_of_credit	Jun. 30, 2018 USD ($) installment_payment	Apr. 11, 2019 USD ($)	Jun. 01, 2017 USD ($)	Apr. 24, 2015 USD ($)	Oct. 24, 2014 USD ($)
Loss Contingencies [Line Items]
Number of outstanding letters of credit | letter_of_credit									2
Outstanding letters of credit amount									$ 500,000
Asset Purchase Agreement - Alternative Fuel Supply Technology
Loss Contingencies [Line Items]
Consideration received on transaction						$ 500,000.0
Payments for commissions						$ 1,200,000
Subsequent Event | Asset Purchase Agreement - Alternative Fuel Supply Technology
Loss Contingencies [Line Items]
Consideration received on transaction					$ 1,500,000
Payments for commissions					1,200,000			$ 400,000
Designation of diesel engines purchased
Loss Contingencies [Line Items]
Number of engines affected | diesel_engine							2,300
Guinta v. Power Solutions International, Inc. | Forecast
Loss Contingencies [Line Items]
Litigation settlement payment	$ 8,500,000
Jerome Treadwell v. The Company | Subsequent Event
Loss Contingencies [Line Items]
Recovery per negligent violation		$ 1,000
Recovery per intentional or reckless violation		$ 5,000
Settled Litigation | Carl Trent, Kenneth Trent, and CKT Holdings, Inc. vs. 3PI and PSI
Loss Contingencies [Line Items]
Range of damages sought												$ 3,000,000
Settlement payments			$ 1,750,000
Legal settlement accrual									$ 625,000
Settled Litigation | Carl Trent, Kenneth Trent, and CKT Holdings, Inc. vs. 3PI and PSI | Forecast
Loss Contingencies [Line Items]
Settlement payments										$ 1,250,000
Number of settlement payments | installment_payment										12
Settled Litigation | Carl Trent, Kenneth Trent, and CKT Holdings, Inc. vs. 3PI and PSI | Tax gross-up payment under the SPA
Loss Contingencies [Line Items]
Damages sought				$ 350,000
Settled Litigation | Carl Trent, Kenneth Trent, and CKT Holdings, Inc. vs. 3PI and PSI | Equity payment due under the SPA
Loss Contingencies [Line Items]
Damages sought				$ 9,300,000
Settled Litigation | Carl Trent, Kenneth Trent, and CKT Holdings, Inc. vs. 3PI and PSI | Compensatory damages | Compensatory damages
Loss Contingencies [Line Items]
Counterclaim damages sought													$ 20,000,000
Settled Litigation | Carl Trent, Kenneth Trent, and CKT Holdings, Inc. vs. 3PI and PSI | Consequential and punitive damages, in excess of | Consequential and punitive damages, in excess of
Loss Contingencies [Line Items]
Counterclaim damages sought													$ 20,000,000
Settled Litigation | Dorvit v. Winemaster | Subsequent Event
Loss Contingencies [Line Items]
Range of damages sought											$ 1,900,000
Minimum | Settled Litigation | Carl Trent, Kenneth Trent, and CKT Holdings, Inc. vs. 3PI and PSI
Loss Contingencies [Line Items]
Range of damages sought														$ 500,000
Maximum | Subsequent Event | Asset Purchase Agreement - Alternative Fuel Supply Technology
Loss Contingencies [Line Items]
Payments for commissions					$ 4,500,000
Maximum | Settled Litigation | Carl Trent, Kenneth Trent, and CKT Holdings, Inc. vs. 3PI and PSI
Loss Contingencies [Line Items]
Range of damages sought														$ 1,000,000