Fair Value Measurements (Details) - USD ($) $ in Millions	12 Months Ended
Mar. 31, 2019	Dec. 31, 2019
Fair Value Measurements [Abstract]
Investments	$ 6.0	$ 4.4
Deferred compensation obligations	6.0	$ 4.4
Decrease in fair value of investments	(1.6)
Decrease in fair value of deferred compensation obligations	$ (1.6)

No definition available.

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- Definition

Fair value of obligations measured on a recurring basis.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

The increase (decrease) during the reporting period in the obligation created by employee agreements whereby earned compensation will be paid in the future.

+ References

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- Definition

Amount of increase (decrease) of investment in debt and equity securities, measured at fair value with changes in fair value recognized in net income.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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-Paragraph 19
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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.4)
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