Name:	gnrc_BusinessAcquisitionPurchasePriceAllocationIntangibleAssetsIncludingGoodwill
Namespace Prefix:	gnrc_
Data Type:	xbrli:monetaryItemType
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The amount, measured at acquisition-date fair value, of all liabilities assumed that arise from contingencies and were recognized by the entity.

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-Publisher FASB
-Name Accounting Standards Codification
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This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
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Name:	us-gaap_Goodwill
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Data Type:	xbrli:monetaryItemType
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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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-Subparagraph (b)
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Name:	us-gaap_StatementBusinessSegmentsAxis=gnrc_DomesticMember
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