Newbuildings (Details) - Newbuildings - USD ($) $ in Millions		6 Months Ended	12 Months Ended
Jul. 02, 2018	Dec. 31, 2018	Jul. 01, 2018	Dec. 31, 2019
Cost
Opening balance	$ 249	$ 249	$ 248	$ 0
Additions			1
Fresh Start adjustments	(249)
Closing balance	0	0	249	0
Net book value	$ 0	$ 249	$ 249	$ 0

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Balance Type:	debit
Period Type:	instant