v3.19.3

Debt Senior Unsecured Notes (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term Debt		$ 10,709		$ 10,709		$ 10,156
Gain (Loss) on Extinguishment of Debt		(12)	$ (1)	(11)	$ (1)
Senior Unsecured Notes 2023 [Member]
Debt Instrument [Line Items]
Long-term Debt	[1]	1,229		1,229		1,227
Senior Unsecured Notes 2024 [Member]
Debt Instrument [Line Items]
Long-term Debt		589		589		599
Senior Unsecured Notes 2025 [Member]
Debt Instrument [Line Items]
Long-term Debt		1,173		1,173		$ 1,210
Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount, Cumulative		438		438
Debt Instrument, Repurchased Face Amount		48		48
Debt Instrument, Repurchase Amount		44		44
Gain (Loss) on Extinguishment of Debt				4
Debt Instrument, Repurchase Amount, Cumulative		$ 399		$ 399
[1] On October 23, 2019, we announced the commencement of a cash tender offer (the “2023 Offer”) for any and all of our outstanding 2023 Senior Unsecured Notes. The 2023 Offer is being made exclusively pursuant to an offer to purchase dated October 23, 2019 (the “Offer to Purchase”), which sets forth the terms and conditions of the 2023 Offer. Consummation of the 2023 Offer is subject to, and conditioned upon, the satisfaction or waiver of certain conditions described in the Offer to Purchase, and is expected to be completed in the fourth quarter of 2019. We may, in our sole discretion, terminate, extend or amend the 2023 Offer at any time as described in the Offer to Purchase.

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