Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Net sales		$ 2,023,464	$ 1,679,373	$ 1,447,743
Costs of goods sold		1,298,424	1,094,587	935,322
Gross profit		725,040	584,786	512,421
Operating expenses:
Selling and service		191,887	174,841	164,860
Research and development		50,019	42,869	37,163
General and administrative		103,841	87,581	74,693
Amortization of intangibles		22,112	28,861	32,953
Total operating expenses		367,859	334,152	309,669
Income from operations		357,181	250,634	202,752
Other (expense) income:
Interest expense		(40,956)	(42,667)	(44,568)
Investment income		1,893	298	44
Loss on extinguishment of debt	[1]	(1,332)		(574)
Loss on change in contractual interest rate	[2]			(2,957)
Other, net		(5,710)	(4,566)	(1,000)
Total other expense, net		(46,105)	(46,935)	(49,055)
Income before provision for income taxes		311,076	203,699	153,697
Provision for income taxes		69,856	44,142	56,519
Net income		241,220	159,557	97,178
Net income attributable to noncontrolling interests		2,963	1,749	24
Net income attributable to Generac Holdings Inc.		$ 238,257	$ 157,808	$ 97,154
Net income attributable to common shareholders per common share - basic: (in dollars per share)		$ 3.57	$ 2.56	$ 1.48
Weighted average common shares outstanding - basic: (in shares)		61,662,031	62,040,704	64,905,793
Net income attributable to common shareholders per common share - diluted: (in dollars per share)		$ 3.54	$ 2.53	$ 1.47
Weighted average common shares outstanding - diluted: (in shares)		62,233,225	62,642,872	65,382,774
Other comprehensive income (loss):
Foreign currency translation adjustment		$ (5,976)	$ 15,191	$ (18,545)
Net unrealized gain on derivatives		2,924	3,712	535
Pension liability adjustment		437	62	322
Other comprehensive income (loss)		(2,615)	18,965	(17,688)
Total comprehensive income		238,605	178,522	79,490
Comprehensive income (loss) attributable to noncontrolling interests		1,647	5,549	(973)
Comprehensive income attributable to Generac Holdings Inc.		$ 236,958	$ 172,973	$ 80,463

[1] Represents the write-off of original issue discount and capitalized debt issuance costs due to voluntary debt prepayments.

[2] For the year ended December 31, 2016, represents a non-cash loss relating to the continued 25 basis point increase in borrowing costs as a result of the credit agreement leverage ratio remaining above 3.0 times based on projections at that time. Following the May 2017 Term Loan amendment, which removed the pricing grid based on leverage ratio achieved, gains or losses on changes in contractual interest rate will no longer be recorded in the statements of comprehensive income. Refer to Note 10, "Credit Agreements," to the consolidated financial statements for further information on the gains and losses on changes in the contractual interest rate.