v3.19.2

Debt Senior Unsecured Notes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term Debt	$ 10,677		$ 10,677		$ 10,156
Gain (Loss) on Extinguishment of Debt	(3)	$ 0	1	$ 0
Senior Unsecured Notes 2023 [Member]
Debt Instrument [Line Items]
Long-term Debt	1,228		1,228		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
Long-term Debt	2,990		2,990		$ 3,036
Debt Instrument, Repurchase Amount	44		44
Gain (Loss) on Extinguishment of Debt			4
Debt Instrument, Repurchase Amount, Cumulative	$ 399		$ 399

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Debt Instrument, Repurchase Amount, Cumulative

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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