Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($)	Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock, Common [Member]	Excess Purchase Price over Predecessor Basis [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Parent [Member]	Noncontrolling Interest [Member]	Total
Balance (in shares) at Dec. 31, 2022	72,701,257		(11,284,350)
Balance at Dec. 31, 2022	$ 728,000	$ 1,016,138,000	$ (808,491,000)	$ (202,116,000)	$ 2,316,224,000	$ (65,102,000)	$ 2,257,381,000	$ 1,874,000	$ 2,259,255,000
Unrealized gain (loss) on interest rate swaps, net of tax						2,309,000	2,309,000		2,309,000
Foreign currency translation adjustment						21,179,000	21,179,000	(38,000)	21,141,000
Common stock issued under equity incentive plans, net of shares withheld for employee taxes and strike price (in shares)	396,713
Common stock issued under equity incentive plans, net of shares withheld for employee taxes and strike price	$ 4,000	2,563,000					2,567,000		2,567,000
Net share settlement of restricted stock awards (in shares)			(45,611)
Net share settlement of restricted stock awards			$ (5,496,000)				(5,496,000)		(5,496,000)
Stock repurchases (in shares)			(875,580)
Stock repurchases			$ (100,267)				(100,267)		(100,267)
Share-based compensation		30,306,000					30,306,000		30,306,000
Net income attributable to Generac Holdings Inc.					118,005,000		118,005,000		118,005,000
Net income								743,000
Net income									118,748,000
Redemption value adjustment					(10,883,000)		(10,883,000)		(10,883,000)
Payment of contingent consideration (in shares)	10,943		466,118
Payment of contingent consideration	$ 0	15,411,000	$ 33,396,000				48,807,000		48,807,000
Balance (in shares) at Sep. 30, 2023	73,108,913		(11,739,423)
Balance at Sep. 30, 2023	$ 732,000	1,064,418,000	$ (880,858,000)	(202,116,000)	2,423,346,000	(41,614,000)	2,363,908,000	2,579,000	2,366,487,000
Balance (in shares) at Jun. 30, 2023	73,097,016		(10,858,348)
Balance at Jun. 30, 2023	$ 732,000	1,053,759,000	$ (779,892,000)	(202,116,000)	2,363,015,000	(16,216,000)	2,419,282,000	2,474,000	2,421,756,000
Unrealized gain (loss) on interest rate swaps, net of tax						1,045,000	1,045,000		1,045,000
Foreign currency translation adjustment						(26,443,000)	(26,443,000)	(93,000)	(26,536,000)
Common stock issued under equity incentive plans, net of shares withheld for employee taxes and strike price (in shares)	11,897
Common stock issued under equity incentive plans, net of shares withheld for employee taxes and strike price	$ 0	732,000					732,000		732,000
Net share settlement of restricted stock awards (in shares)			(5,495)
Net share settlement of restricted stock awards			$ (699,000)				(699,000)		(699,000)
Stock repurchases (in shares)			(875,580)
Stock repurchases			$ (100,267)				(100,267)		(100,267)
Share-based compensation		9,927,000					9,927,000		9,927,000
Net income attributable to Generac Holdings Inc.					60,377,000		60,377,000		60,377,000
Net income								198,000
Net income									60,575,000
Redemption value adjustment					(46,000)		(46,000)		(46,000)
Balance (in shares) at Sep. 30, 2023	73,108,913		(11,739,423)
Balance at Sep. 30, 2023	$ 732,000	1,064,418,000	$ (880,858,000)	(202,116,000)	2,423,346,000	(41,614,000)	2,363,908,000	2,579,000	2,366,487,000
Balance (in shares) at Dec. 31, 2023	73,195,055		(13,057,298)
Balance at Dec. 31, 2023	$ 733,000	1,070,386,000	$ (1,032,921,000)	(202,116,000)	2,519,313,000	(15,143,000)	2,340,252,000	2,818,000	2,343,070,000
Unrealized gain (loss) on interest rate swaps, net of tax						(9,925,000)	(9,925,000)		(9,925,000)
Foreign currency translation adjustment						(2,919,000)	(2,919,000)	54,000	(2,865,000)
Common stock issued under equity incentive plans, net of shares withheld for employee taxes and strike price (in shares)	451,365
Common stock issued under equity incentive plans, net of shares withheld for employee taxes and strike price	$ 3,000	6,869,000					6,872,000		6,872,000
Net share settlement of restricted stock awards (in shares)			(54,281)
Net share settlement of restricted stock awards			$ (6,771,000)				(6,771,000)		(6,771,000)
Stock repurchases (in shares)			(1,046,351)
Stock repurchases			$ (152,743,000)				(152,743,000)		(152,743,000)
Share-based compensation		38,270,000					38,270,000		38,270,000
Net income attributable to Generac Holdings Inc.					199,089,000		199,089,000		199,089,000
Net income								151,000
Net income									199,240,000
Redemption value adjustment					(2,686,000)		(2,686,000)		(2,686,000)
Balance (in shares) at Sep. 30, 2024	73,646,420		(14,149,513)
Balance at Sep. 30, 2024	$ 736,000	1,115,525,000	$ (1,192,435,000)	(202,116,000)	2,715,716,000	(27,987,000)	2,409,439,000	3,023,000	2,412,462,000
Balance (in shares) at Jun. 30, 2024	73,608,578		(13,446,797)
Balance at Jun. 30, 2024	$ 736,000	1,101,074,000	$ (1,088,426,000)	(202,116,000)	2,601,974,000	(43,529,000)	2,369,713,000	2,806,000	2,372,519,000
Unrealized gain (loss) on interest rate swaps, net of tax						(10,177,000)	(10,177,000)		(10,177,000)
Foreign currency translation adjustment						25,719,000	25,719,000	181,000	25,900,000
Common stock issued under equity incentive plans, net of shares withheld for employee taxes and strike price (in shares)	37,842
Common stock issued under equity incentive plans, net of shares withheld for employee taxes and strike price	$ 0	1,336,000					1,336,000		1,336,000
Net share settlement of restricted stock awards (in shares)			(12,005)
Net share settlement of restricted stock awards			$ (1,875,000)				(1,875,000)		(1,875,000)
Stock repurchases (in shares)			(690,711)
Stock repurchases			$ (102,134)				(102,134)		(102,134)
Share-based compensation		13,115,000					13,115,000		13,115,000
Net income attributable to Generac Holdings Inc.					113,742,000		113,742,000		113,742,000
Net income								36,000
Net income									113,778,000
Redemption value adjustment									0
Balance (in shares) at Sep. 30, 2024	73,646,420		(14,149,513)
Balance at Sep. 30, 2024	$ 736,000	$ 1,115,525,000	$ (1,192,435,000)	$ (202,116,000)	$ 2,715,716,000	$ (27,987,000)	$ 2,409,439,000	$ 3,023,000	$ 2,412,462,000