Income Taxes - Roll forward of interest accrued on unrecognized tax benefits (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Accrued interest on the consolidated balance sheets	$ 0.1	$ 0.5	$ 0.8	$ 0.7
Interest expense (income) related to unrecognized tax benefits	(0.4)	(0.3)	0.1
Penalties in the consolidated income statements	0.0	0.0	$ 0.0
Accrued penalties on the consolidated balance sheets	0.0	$ 0.0
Unrecognized tax benefits, decrease resulting from statute of limitations	$ 2.1

No definition available.

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- Definition

Amount of statutory penalties accrued for a tax position claimed or expected to be claimed by the entity, in its tax return.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32718-109319

+ Details

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- Definition

Amount of expense for penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

+ Details

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- Definition

Amount of interest expense accrued for an underpayment of income taxes.

+ References

+ Details

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- Definition

Amount of interest expense for an underpayment of income taxes.

+ References

+ Details

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- Definition

Unrecognized tax benefits, decrease possible in the next 12 months resulting from statute of limitations

+ References

No definition available.

+ Details

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