Amount of amortization expense attributable to debt discount (premium) and debt issuance costs.

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Debt (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Debt (Details) - USD ($) $ in Millions	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Debt Instrument [Line Items]
Debt	$ 8,658		$ 8,658		$ 7,326
Amortization included in interest expense	3	$ 1	4	$ 2
Holding Company
Debt Instrument [Line Items]
Debt	6,755		6,755		5,505
Energy Segment
Debt Instrument [Line Items]
Debt	1,195		1,195		1,170
Automotive Segment
Debt Instrument [Line Items]
Debt	406		406		372
Food Packaging Segment
Debt Instrument [Line Items]
Debt	270		270		273
Metals Segment
Debt Instrument [Line Items]
Debt	10		10		0
Real Estate Segment
Debt Instrument [Line Items]
Debt	2		2		2
Home Fashion Segment
Debt Instrument [Line Items]
Debt	20		20		4
Reporting Segments
Debt Instrument [Line Items]
Debt	1,903		1,903		1,821
6.000% senior unsecured notes due 2020 \| Holding Company
Debt Instrument [Line Items]
Debt	1,701		1,701		1,702
5.875% senior unsecured notes due 2022 \| Holding Company
Debt Instrument [Line Items]
Debt	1,345		1,345		1,344
6.250% senior unsecured notes due 2022 \| Holding Company
Debt Instrument [Line Items]
Debt	1,212		1,212		1,213
6.750% senior unsecured notes due 2024 \| Holding Company
Debt Instrument [Line Items]
Debt	498		498		498
6.375% senior unsecured notes due 2025 \| Holding Company
Debt Instrument [Line Items]
Debt	748		748		748
6.250% senior unsecured notes due 2026 \| Holding Company
Debt Instrument [Line Items]
Face value of debit issued	$ 1,250		$ 1,250
Interest rate on debt issued	6.25%		6.25%
Debt	$ 1,251		$ 1,251		$ 0