Debt (Details Textual) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
2018 Revolver [Member]
Debt Instrument [Line Items]
Secured Long-term Debt, Noncurrent	$ 0.0	$ 800.0
Secured Debt Term A [Member]
Debt Instrument [Line Items]
Secured Long-term Debt, Noncurrent	$ 0.0	415.7
Senior Unsecured Notes Due 2023 [Member] [Domain]
Debt Instrument [Line Items]
Fixed interest rate	3.95%
Senior Unsecured Notes Due 2028 [Member]
Debt Instrument [Line Items]
Fixed interest rate	4.60%
Senior Secured Notes Due 2026 [Member]
Debt Instrument [Line Items]
Secured Long-term Debt, Noncurrent	$ 298.1	$ 297.8
Fixed interest rate	3.85%

Contractual interest rate for funds borrowed, under the debt agreement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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+ References

No definition available.

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- Definition

Carrying amount of collateralized debt obligations with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion. Obligations include, but not limited to, mortgage loans, chattel loans, and other borrowings secured by assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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