Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)	3 Months Ended	6 Months Ended
	Mar. 31, 2020	Jun. 30, 2020	Feb. 14, 2020	Dec. 31, 2019	Dec. 27, 2017
Summary Of Significant Accounting Policies [Line Items]
Goodwill impairment	$ 0	$ 0
Offering costs offset from proceeds of reverse capitalization		2,600,000
Deferred as prepaid expenses and other current assets	$ 7,600,000			$ 700,000
Offering costs reclassified as additional paid-in-capital		400,000
Federal tax expense (benefit)		$ 0
Partnership owned percentage in operating entity		100.00%
Preferred stock, shares authorized		1,000,000
Preferred stock, par value		$ 0.0001
Preferred stock, shares issued		0
Class of Warrant or Right, Outstanding		8,668,750			33,333.33
Warrants expire term		5 years
Warrants
Summary Of Significant Accounting Policies [Line Items]
Share Price		$ 11.50
Accounting Standards Update Topic840
Summary Of Significant Accounting Policies [Line Items]
Each warrant exercisable for common stock		1
Alta Equipment Holdings, Inc. | Reverse Recapitalization
Summary Of Significant Accounting Policies [Line Items]
Capital stock, shares authorized			201,000,000
Common stock, shares authorized			200,000,000
Preferred stock, shares authorized			1,000,000
Preferred stock, par value			$ 0.0001
Preferred stock, shares issued		0