Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Unamortized Intangible Assets
Amortization expense of intangible assets	$ 10.7	$ 6.4	$ 17.2	$ 11.3
Estimated average amortization, year one	44.9		44.9
Estimated average amortization, year two	44.9		44.9
Estimated average amortization, year three	44.9		44.9
Estimated average amortization, year four	44.9		44.9
Estimated average amortization, year five	44.9		44.9
AMS
Amortized Intangible Assets
Gross Carrying Amount	665.1		665.1		$ 419.0
Accumulated Amortization	124.4		124.4		106.9
Accumulated Impairments	20.7		20.7		20.7
Accumulated Foreign Exchange	(1.5)		(1.5)		(2.8)
Net Carrying Amount	521.5		521.5		294.2
AMS \| Trade names
Amortized Intangible Assets
Accumulated Impairments	0.1		0.1		0.1
Accumulated Foreign Exchange	(0.3)		(0.3)		(0.6)
Unamortized Intangible Assets
Gross Carrying Amount	20.0		20.0		20.0
Net Carrying Amount	20.2		20.2		20.5
AMS \| Customer relationships
Amortized Intangible Assets
Gross Carrying Amount	540.9		540.9		339.8
Accumulated Amortization	102.6		102.6		88.5
Accumulated Impairments	0.0		0.0		0.0
Accumulated Foreign Exchange	(1.9)		(1.9)		(2.9)
Net Carrying Amount	440.2		440.2		254.2
AMS \| Developed technology
Amortized Intangible Assets
Gross Carrying Amount	79.4		79.4		42.1
Accumulated Amortization	16.8		16.8		14.1
Accumulated Impairments	0.0		0.0		0.0
Accumulated Foreign Exchange	0.1		0.1		(0.2)
Net Carrying Amount	62.5		62.5		28.2
AMS \| Trade names
Amortized Intangible Assets
Gross Carrying Amount	40.4		40.4		32.7
Accumulated Amortization	2.0		2.0		1.4
Accumulated Impairments	20.7		20.7		20.7
Accumulated Foreign Exchange	0.3		0.3		0.3
Net Carrying Amount	17.4		17.4		10.3
AMS \| Non-compete agreements
Amortized Intangible Assets
Gross Carrying Amount	2.9		2.9		2.9
Accumulated Amortization	2.4		2.4		2.4
Accumulated Impairments	0.0		0.0		0.0
Accumulated Foreign Exchange	0.0		0.0		0.0
Net Carrying Amount	0.5		0.5		0.5
AMS \| Patents
Amortized Intangible Assets
Gross Carrying Amount	1.5		1.5		1.5
Accumulated Amortization	0.6		0.6		0.5
Accumulated Impairments	0.0		0.0		0.0
Accumulated Foreign Exchange	0.0		0.0		0.0
Net Carrying Amount	$ 0.9		$ 0.9		$ 1.0

Indefinite-Lived Intangible Assets (Excluding Goodwill), Gross

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Intangible Assets, Accumulated Foreign Exchange Gain (Loss)

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Intangible Assets, Accumulated Impairment Loss

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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