Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Expected Indexation

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Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Expected Rate of Return on Plan Assets

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

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Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

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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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Acquisitions, Goodwill And Other Intangible Assets (Narrative) (Details) - USD ($) $ in Thousands	1 Months Ended			3 Months Ended	6 Months Ended
	Jan. 31, 2020	Dec. 31, 2019	Aug. 31, 2019	Mar. 31, 2020	Jun. 30, 2020	Jun. 30, 2019
Business Acquisition [Line Items]
Cash consideration, net of cash acquired					$ 94,713	$ 8,530
Benefit obligation measurement, discount rate					1.20%
Benefit obligation measurement, expected rate of return on plan assets					1.20%
Benefit obligation measurement, wage inflation					2.00%
Minimum
Business Acquisition [Line Items]
Benefit obligation measurement, expected indexation					0.00%
Maximum
Business Acquisition [Line Items]
Benefit obligation measurement, expected indexation					2.00%
Polyplastic
Business Acquisition [Line Items]
Percentage of interests acquired	100.00%
Cash consideration, net of cash acquired	$ 95,766
Contingent consideration maximum	$ 7,700
Acquired intangible assets useful life	15 years
Total fair value of consideration given	$ 98,562
CURT
Business Acquisition [Line Items]
Percentage of interests acquired		100.00%
Cash consideration, net of cash acquired		$ 337,640			$ 336,587
CURT \| Minimum
Business Acquisition [Line Items]
Acquired intangible assets useful life		16 years
CURT \| Maximum
Business Acquisition [Line Items]
Acquired intangible assets useful life		20 years
Lewmar Marine Limited
Business Acquisition [Line Items]
Percentage of interests acquired			100.00%
Cash consideration, net of cash acquired				$ 43,224	$ 43,224
Total fair value of consideration given			$ 43,200
Lewmar Marine Limited \| Customer Relationships
Business Acquisition [Line Items]
Acquired intangible assets useful life			15 years