PROPERTY PLANT AND EQUIPMENT (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Reconciliation of changes in property, plant and equipment [abstract]
Beginning Balance		$ 6,947
Ending Balance	$ 13,859	13,859	$ 6,947
Right-of-use assets	1,144	1,144
Teekay Offshore \| Vessels
Reconciliation of changes in property, plant and equipment [abstract]
Impairment expense	63	63
Gross Carrying Amount
Reconciliation of changes in property, plant and equipment [abstract]
Beginning Balance		8,415	3,425
Additions		594	500
Disposals		(143)	(131)
Acquisitions through business combinations		6,141	4,913
Transfers and assets reclassified as held for sale		(223)	(38)
Changes in accounting policy		978	0
Net foreign currency exchange differences		105	(254)
Ending Balance	15,867	15,867	8,415
Accumulated Depreciation and Impairment
Reconciliation of changes in property, plant and equipment [abstract]
Beginning Balance		(1,468)	(895)
Depreciation/depletion/impairment expense		(582)	(720)
Disposals		62	62
Transfers and assets reclassified as held for sale		28	2
Net foreign currency exchange differences		(48)	83
Ending Balance	$ (2,008)	$ (2,008)	$ (1,468)

Increase (Decrease) Due To Change In Accounting Policy, Property, Plant And Equipment

No definition available.

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- Definition

The increase in property, plant and equipment resulting from acquisitions through business combinations. [Refer: Business combinations [member]; Property, plant and equipment]

+ References

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The amount of additions to property, plant and equipment other than those acquired through business combinations. [Refer: Business combinations [member]; Property, plant and equipment]

+ References

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- Definition

The amount of depreciation of property, plant and equipment. [Refer: Depreciation and amortisation expense; Property, plant and equipment]

+ References

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- Definition

The decrease in property, plant and equipment resulting from disposals. [Refer: Property, plant and equipment]

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- Definition

The amount of impairment loss recognised in profit or loss for property, plant and equipment. [Refer: Impairment loss recognised in profit or loss; Property, plant and equipment]

+ References

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The increase (decrease) in property, plant and equipment resulting from net exchange differences arising on the translation of the financial statements from the functional currency into a different presentation currency, including the translation of a foreign operation into the presentation currency of the reporting entity. [Refer: Property, plant and equipment]

+ References

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The increase (decrease) in property, plant and equipment resulting from transfers. [Refer: Property, plant and equipment]

+ References

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- Definition

The amount of tangible assets that: (a) are held for use in the production or supply of goods or services, for rental to others, or for administrative purposes; and (b) are expected to be used during more than one period.

+ References

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No definition available.

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- Definition

The amount of assets that represent a lessee's right to use an underlying asset for the lease term. Underlying asset is an asset that is the subject of a lease, for which the right to use that asset has been provided by a lessor to a lessee.

+ References

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