Condensed Consolidated Statements of Operations Condensed Consolidated Statement of Operations (parentheticals) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Discontinued Operation, Tax Effect of Income (Loss) from Discontinued Operation During Phase-out Period	$ 0	$ 0
Discontinued Operation, Tax Effect of Gain (Loss) from Disposal of Discontinued Operation	$ 0	$ 0

Amount of tax expense (benefit) on gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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