Acquisitions, Divestitures and Discontinued Operations Acquisitions and Divestitures, Investments in Unconsolidated Affiliates (Details) - Variable Interest Entity, Not Primary Beneficiary [Member] - Peak Nano [Member] - USD ($) $ in Millions	Mar. 06, 2019	Feb. 16, 2018
Schedule of Equity Method Investments [Line Items]
Investment in nonconsolidated affiliate (percent)		25.00%
Purchase price	$ 20	$ 20
Conversion of note receivable	$ 5
Additional interest acquired (percent)	10.00%
Warrants to acquire additional interest (percent)	10.00%