Description of Business and Summary of Significant Accounting Policies - Additional Information (Details)		1 Months Ended	3 Months Ended											12 Months Ended
	Mar. 09, 2021 USD ($) Installment	Oct. 31, 2018 USD ($)	Mar. 31, 2021 USD ($) Installment	Dec. 31, 2020 USD ($)	Mar. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($) Facility State Customer shares	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($) Customer shares	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2019 USD ($) Vehicle Station Facility State Acquisition Customer $ / shares shares	Dec. 31, 2018 USD ($) Customer $ / shares shares	Dec. 31, 2017 USD ($)	Jun. 30, 2021 USD ($) $ / shares shares	Jun. 30, 2020 USD ($)	Feb. 27, 2020 shares	Jan. 01, 2019 USD ($)	Jan. 01, 2018 USD ($)
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Number of vehicles in operation | Vehicle														1,000
Number of facilities in operation | Facility						15								15
Number of States in which entity operates | State						17								17
Number of acquisitions completed | Acquisition														7
Cash						$ 3,274,000				$ 1,630,000				$ 3,274,000	$ 1,630,000
Working capital deficit						66,200,000								66,200,000
Stockholders' deficit						(12,673,000)				$ (11,666,000)				(12,673,000)	(11,666,000)	$ (14,163,000)
Debt and lease obligations						$ 72,800,000								72,800,000
Cash used in operating activities														15,178,000	6,783,000
Net loss														$ (32,714,000)	$ (6,577,000)
Common stock, shares issued | shares						14,333,834				2,258,530				14,333,834	2,258,530
Repayment of factor advances		$ 100,000													$ 105,000
Cash equivalents						$ 0				$ 0				$ 0	$ 0
Number of major customers | Customer						1				1				1	1
Goodwill impairment charges														$ 0	$ 0
Indefinite-lived intangible assets						$ 0				$ 0				0	0
Long-lived asset impairment charges														3,616,000	240,000
Cumulative effect adjustments						(54,771,000)		$ (36,511,000)	$ (29,498,000)	(22,057,000)	$ (21,233,000)	$ (18,014,000)	$ (15,361,000)	(54,771,000)	(22,057,000)						$ (15,463,000)
Unrecognized income tax benefits														$ 0	$ 0
Impact on earnings per share | $ / shares														$ (2.89)	$ (3.46)
Previously Reported [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Stockholders' deficit																(12,775,000)
Net loss						0	$ 0	0	0	0	0	0	0	$ 0	$ 0
Cumulative effect adjustments								$ (35,123,000)	$ (28,110,000)	$ (20,669,000)	$ (19,845,000)	$ (16,626,000)	$ (13,973,000)		$ (20,669,000)						(14,075,000)
Net loss previously reported understated amount																1,400,000
Current liabilities, previously reported understated amount																(1,400,000)
Accumulated deficit previously reported understated amount																$ 1,400,000
Error corrections, description														The Company assessed the materiality of the error, both quantitatively and qualitatively, and concluded that the error was not material to any of its previously reported financial statements for annual or interim periods based upon qualitative aspects of the error. However, as the error was large quantitatively, the Company determined that the correction of this error would have a material effect on the financial results for the three and nine months ended September 30, 2019. Accordingly, previously issued financial statements have been revised to correct the error. The revision applies to the previously reported amount for accumulated deficit in the consolidated statement of stockholders’ deficit as of January 1, 2018 and the previously reported amounts for current liabilities and accumulated deficit in the consolidated balance sheets as of March 31, 2018, June 30, 2018, September 30, 2018, December 31, 2018, March 31, 2019, and June 30, 2019.
ASU 2014-09 [Member] | Revision of Prior Period, Change in Accounting Principle, Adjustment
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Cumulative effect adjustments																					$ 0
ASU 2016-02 [Member] | Revision of Prior Period, Change in Accounting Principle, Adjustment
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Cumulative effect adjustments																				$ 0
Minimum [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Financing transactions, award grant														$ 30,000,000
USPS [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Contractual payment terms														There is no significant financing component in the transaction price, as the USPS generally pays within the contractual payment terms of 30 to 60 days.
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Trucking [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Percentage of concentrations of credit risk														65.00%	99.00%
Revenue Benchmark [Member] | Customer Concentration Risk [Member] | USPS [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Percentage of concentrations of credit risk														88.00%	95.00%
Revenue Benchmark [Member] | Customer Concentration Risk [Member] | Trucking [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Percentage of concentrations of credit risk														88.00%	97.00%
Subsequent Event [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Aggregate gross proceeds pursuant to terms of subscription agreement					$ 6,200,000
Series B Preferred Stock [Member] | Subsequent Event [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Preferred stock issued | shares					1,000,000
Common Stock
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Stockholders' deficit						1,000								$ 1,000
Common Stock | Subsequent Event [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Common stock, shares issued | shares					1,260,000														1,260,000
Forecast [Member] | Triumph Business Capital [Member] | Letter of Intent and Memo of Understanding [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Proceeds from transportation settlements	$ 17,500,000		$ 17,500,000
Repayment of factor advances	11,000,000.0		11,000,000.0
Amount retained to reduce outstanding principal amount of factoring advances	$ 6,900,000		$ 6,900,000
Number of installments for repayment | Installment	48		48
Frequency of payments	monthly		monthly
Date of first required payment	Jan. 01, 2022		Jan. 01, 2022
Funds held in reserve against advances	$ 800,000		$ 800,000
Forecast [Member] | USPS [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Compensation received for work performed			$ 28,400,000
Note Purchase Agreements and Releases [Member] | Forecast [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Principal amount																	$ 600,000
Notes payable in cash																	$ 100,000
Warrants to purchase shares of common stock | shares																	231,453
Warrants, exercise price | $ / shares																	$ 0.01
Paycheck Protection Program Loan, CARES Act [Member] | Forecast [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Principal amount																		$ 10,000,000.0
Loan Agreement [Member] | Main Street Loan [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Principal amount due						$ 25,400,000								$ 25,400,000
Maturity date														Sep. 16, 2022
Loan Agreement [Member] | Main Street Loan [Member] | Subsequent Event [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Principal amount due					$ 31,700,000
Loan Agreement [Member] | Main Street Loan [Member] | Forecast [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Principal amount due				$ 16,700,000
Principal amount				$ 17,000,000.0
Debt instrument description				the forbearance period related to the remaining Antara debt was terminated and all existing defaults and events of defaults were waived, and the maturity date of the remaining outstanding term loan balance under the Antara Financing Agreement was extended from September 16, 2022 to the earlier of the date that is ninety-one days after the fifth anniversary of the closing date of the Main Street Loan or the date that is ninety-one days after the date the Main Street Loan is paid in full.
Financing Agreement [Member] | Forecast [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Loan obtained					$ 6,300,000
CNG [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Number of vehicles in operation | Vehicle														200
Number of fueling stations | Station														1
Number of dedicated stations | Station														5