SUBSEQUENT EVENTS - Additional Information (Detail)				1 Months Ended
	Nov. 12, 2021 USD ($)	Oct. 13, 2021 USD ($)	Sep. 15, 2021 USD ($)	Oct. 31, 2021 USD ($) a ft²	Oct. 06, 2021 shares	Sep. 30, 2021 shares	Dec. 31, 2020 shares
Subsequent Event [Line Items]
Net Proceeds After Discounts and Commissions, Before Expenses and Payment of Structuring Fee		$ 53,300,000
Land Purchase Description				a Delaware corporation, pursuant to which Greenidge has agreed to purchase from the seller two parcels of land containing approximately 175 acres of land located in Spartanburg, South Carolina, including over 750,000 square feet of industrial buildings (the “Property”)
Area Of Land | ft²				750,000
Common stock, shares issued | shares						38,667,705	0
Series of Individually Immaterial Asset Acquisitions [Member]
Subsequent Event [Line Items]
Purchase Price of the Property				$ 15,000,000.0
Land [Member]
Subsequent Event [Line Items]
Area Of Land | a				175
Common Class A [Member]
Subsequent Event [Line Items]
Common stock, shares issued | shares						9,627,705
Common Class B [Member]
Subsequent Event [Line Items]
Common stock, shares issued | shares						29,040,000
Greenidge Generation Holdings Inc [Member]
Subsequent Event [Line Items]
Registered public offering		$ 55,200,000
Senior Notes Due		8.50%
Common Stock Purchase Agreement and Registration Rights Agreement [Member] | Common Class A [Member]
Subsequent Event [Line Items]
Proceeds from common stock purchase agreement			$ 500,000
Common Stock Purchase Agreement and Registration Rights Agreement [Member] | Greenidge Generation Holdings Inc [Member] | Private Placement [Member]
Subsequent Event [Line Items]
Proceeds from common stock purchase agreement			$ 200,000,000
L S C Agreement [Member]
Subsequent Event [Line Items]
Escrow Deposit				$ 2,500,000
Subsequent Event [Member] | Common Stock Purchase Agreement and Registration Rights Agreement [Member] | Common Class A [Member]
Subsequent Event [Line Items]
Common stock, shares issued | shares					3,500,000
Sale of stock	$ 1,977,500
Proceeds from sale of stock	$ 47,900,000