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
Debt (Details) - USD ($) $ in Millions	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Debt Instrument [Line Items]
Debt	$ 7,392		$ 7,326
Amortization included in interest expense	1	$ 1
Holding Company
Debt Instrument [Line Items]
Debt	5,505		5,505
Energy Segment
Debt Instrument [Line Items]
Debt	1,196		1,170
Automotive Segment
Debt Instrument [Line Items]
Debt	405		372
Food Packaging Segment
Debt Instrument [Line Items]
Debt	271		273
Metals Segment
Debt Instrument [Line Items]
Debt	1		0
Real Estate Segment
Debt Instrument [Line Items]
Debt	2		2
Home Fashion Segment
Debt Instrument [Line Items]
Debt	12		4
Reporting Segments
Debt Instrument [Line Items]
Debt	1,887		1,821
6.000% senior unsecured notes due 2020 \| Holding Company
Debt Instrument [Line Items]
Debt	1,702		1,702
5.875% senior unsecured notes due 2022 \| Holding Company
Debt Instrument [Line Items]
Debt	1,344		1,344
6.250% senior unsecured notes due 2022 \| Holding Company
Debt Instrument [Line Items]
Debt	1,213		1,213
6.750% senior unsecured notes due 2024 \| Holding Company
Debt Instrument [Line Items]
Debt	498		498
6.375% senior unsecured notes due 2025 \| Holding Company
Debt Instrument [Line Items]
Debt	$ 748		$ 748