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
Balance (in shares) at Mar. 31, 2023	73,052,760		(10,855,203)
Balance at Mar. 31, 2023	$ 731,000	1,042,786,000	$ (779,533,000)	(202,116,000)	2,319,638,000	(42,343,000)	2,339,163,000	2,216,000	2,341,379,000
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						1,264,000	1,264,000		1,264,000
Foreign currency translation adjustment						47,622,000	47,622,000	55,000	47,677,000
Common stock issued under equity incentive plans, net of shares withheld for employee taxes and strike price (in shares)	384,816
Common stock issued under equity incentive plans, net of shares withheld for employee taxes and strike price	$ 4,000	1,832,000					1,836,000		1,836,000
Net share settlement of restricted stock awards (in shares)			(40,116)
Net share settlement of restricted stock awards			$ (4,797,000)				(4,797,000)		(4,797,000)
Share-based compensation		20,379,000					20,379,000		20,379,000
Net income attributable to Generac Holdings Inc.					57,628,000		57,628,000		57,628,000
Net income (loss)								545,000
Net income (loss)									58,173,000
Redemption value adjustment					(10,837,000)		(10,837,000)		(10,837,000)
Payment of contingent consideration (in shares)	10,943		466,118
Payment of contingent consideration	$ 0	15,410,000	$ 33,396,000				48,806,000		48,806,000
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
Balance (in shares) at Mar. 31, 2023	73,052,760		(10,855,203)
Balance at Mar. 31, 2023	$ 731,000	1,042,786,000	$ (779,533,000)	(202,116,000)	2,319,638,000	(42,343,000)	2,339,163,000	2,216,000	2,341,379,000
Unrealized gain (loss) on interest rate swaps, net of tax						5,752,000	5,752,000		5,752,000
Foreign currency translation adjustment						20,375,000	20,375,000	(5,000)	20,370,000
Common stock issued under equity incentive plans, net of shares withheld for employee taxes and strike price (in shares)	44,256
Common stock issued under equity incentive plans, net of shares withheld for employee taxes and strike price	$ 1,000	928,000					929,000		929,000
Net share settlement of restricted stock awards (in shares)			(3,145)
Net share settlement of restricted stock awards			$ (359,000)				(359,000)		(359,000)
Share-based compensation		10,045,000					10,045,000		10,045,000
Net income attributable to Generac Holdings Inc.					45,198,000		45,198,000		45,198,000
Net income (loss)								263,000
Net income (loss)									45,461,000
Redemption value adjustment					(1,821,000)		(1,821,000)		(1,821,000)
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
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
Balance (in shares) at Mar. 31, 2024	73,492,146		(13,087,185)
Balance at Mar. 31, 2024	$ 735,000	1,081,985,000	$ (1,037,227,000)	(202,116,000)	2,542,859,000	(18,832,000)	2,367,404,000	2,908,000	2,370,312,000
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						252,000	252,000		252,000
Foreign currency translation adjustment						(28,638,000)	(28,638,000)	(127,000)	(28,765,000)
Common stock issued under equity incentive plans, net of shares withheld for employee taxes and strike price (in shares)	413,523
Common stock issued under equity incentive plans, net of shares withheld for employee taxes and strike price	$ 3,000	5,533,000					5,536,000		5,536,000
Net share settlement of restricted stock awards (in shares)			(42,276)
Net share settlement of restricted stock awards			$ (4,896,000)				(4,896,000)		(4,896,000)
Stock repurchases (in shares)			(355,640)
Stock repurchases			$ (50,609,000)				(50,609,000)		(50,609,000)
Share-based compensation		25,155,000					25,155,000		25,155,000
Net income attributable to Generac Holdings Inc.					85,347,000		85,347,000		85,347,000
Net income (loss)								115,000
Net income (loss)									85,462,000
Redemption value adjustment					(2,686,000)		(2,686,000)		(2,686,000)
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
Balance (in shares) at Mar. 31, 2024	73,492,146		(13,087,185)
Balance at Mar. 31, 2024	$ 735,000	1,081,985,000	$ (1,037,227,000)	(202,116,000)	2,542,859,000	(18,832,000)	2,367,404,000	2,908,000	2,370,312,000
Unrealized gain (loss) on interest rate swaps, net of tax						(1,730,000)	(1,730,000)		(1,730,000)
Foreign currency translation adjustment						(22,967,000)	(22,967,000)	(40,000)	(23,007,000)
Common stock issued under equity incentive plans, net of shares withheld for employee taxes and strike price (in shares)	116,432
Common stock issued under equity incentive plans, net of shares withheld for employee taxes and strike price	$ 1,000	6,374,000					6,375,000		6,375,000
Net share settlement of restricted stock awards (in shares)			(3,972)
Net share settlement of restricted stock awards			$ (590,000)				(590,000)		(590,000)
Stock repurchases (in shares)			(355,640)
Stock repurchases			$ (50,609)				(50,609)		(50,609)
Share-based compensation		12,715,000					12,715,000		12,715,000
Net income attributable to Generac Holdings Inc.					59,115,000		59,115,000		59,115,000
Net income (loss)								(62,000)
Net income (loss)									59,053,000
Redemption value adjustment									0
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