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Number of shares of equity interests issued or issuable to acquire entity.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

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-Publisher FASB
-Name Accounting Standards Codification
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The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Equity (Details) - USD ($) shares in Millions, $ in Millions						9 Months Ended
	Sep. 04, 2018	Jun. 11, 2018	Mar. 28, 2018	Jan. 30, 2018	Jan. 16, 2018	Sep. 30, 2018	Dec. 31, 2017
Variable Interest Entity
Payment to acquire interest						$ 107
Acquisition of redeemable noncontrolling interest						53
Songa
Carrying amounts associated with consolidated variable interest entities
Newly issued shares (in shares)			68.0	66.9
Songa \| Maximum
Carrying amounts associated with consolidated variable interest entities
Newly issued shares (in shares)					68.6
Ocean Rig
Carrying amounts associated with consolidated variable interest entities
Newly issued shares (in shares)	147.7
ADDCL
Variable Interest Entity
Ownership interest in affiliate (as a percent)		65.00%
ADDCL
Variable Interest Entity
Payment to acquire interest		$ 0
Acquisition of redeemable noncontrolling interest						$ 53
Carrying amounts associated with consolidated variable interest entities
Assets							$ 716
Liabilities							$ 7
ADDCL \| Angco Cayman Limited
Variable Interest Entity
Ownership interest held by minority interest (as a percent)		35.00%