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Business Combinations, Goodwill and Intangible Assets, Business Combinations (Details) - USD ($) $ in Millions		12 Months Ended
	Sep. 19, 2018	Dec. 31, 2018	Dec. 31, 2017
Business Combination Segment Allocation [Line Items]
Goodwill		$ 62.4	$ 37.2
Imperial Machine and Tool Co. (''IMT'') [Member]
Business Combination Segment Allocation [Line Items]
Cash	$ 0.9
Accounts receivable	2.6
Prepaid expenses and other current assets	0.6
Inventory	2.9
Property, plant and equipment	4.1
Identifiable intangible assets with definite lives	9.2
Goodwill	25.2
Accounts payable and other current liabilities	(1.4)
Total purchase price	44.1
Purchase price, net of cash acquired	$ 43.2
Acquisition-related costs		$ 0.6