Other Financial Information - Narrative (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Other Financial Information [Abstract]
Net gains (losses) from foreign currency transactions		$ (6.0)	$ 16.1	$ (82.7)
Increase (Decrease) in Asset Retirement Obligations	$ 37.3

Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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