XML 58 R40.htm IDEA: XBRL DOCUMENT v3.8.0.1

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2017

Income Tax Disclosure [Abstract]

Components of income tax expense

Components of income tax expense are as follows (in millions):

	Year Ended December 31,
	2017				2016				2015
Current income tax expense:
State income tax	$	1			$	2			$	1
Canadian federal and provincial income tax	27				83				83
Total current income tax expense	$	28			$	85			$	84
Deferred income tax expense/(benefit):
Canadian federal and provincial income tax	$	16			$	(60	)		$	16
Total deferred income tax expense/(benefit)	$	16			$	(60	)		$	16
Total income tax expense	$	44			$	25			$	100

Summary of differences between tax expense based on the statutory federal income tax rate and the effective income tax expense

The difference between income tax expense based on the statutory federal income tax rate and our effective income tax expense is summarized as follows (in millions):

	Year Ended December 31,
	2017				2016				2015
Income before tax	$	902			$	755			$	1,006
Partnership earnings not subject to current Canadian tax	(756		)		(723		)		(773		)
	$	146			$	32			$	233
Canadian federal and provincial corporate tax rate	27		%		27		%		26		%
Income tax at statutory rate	$	39			$	8			$	61
Canadian withholding tax	$	2			$	13			$	14
Canadian permanent differences and rate changes	2				2				24
State income tax	1				2				1
Total income tax expense	$	44			$	25			$	100

Deferred tax assets and liabilities

Deferred tax assets and liabilities are aggregated by the applicable tax paying entity and jurisdiction and result from the following (in millions):

	December 31,
	2017				2016
Deferred tax assets:
Derivative instruments	$	74			$	49
Book accruals in excess of current tax deductions	22				24
Net operating losses	3				4
Total deferred tax assets	99				77
Deferred tax liabilities:
Property and equipment in excess of tax values	(455		)		(394		)
Other	(50		)		(41		)
Total deferred tax liabilities	(505		)		(435		)
Net deferred tax liabilities	$	(406	)		$	(358	)
Balance sheet classification of deferred tax assets/(liabilities):
Other long-term assets, net	$	3			$	4
Other long-term liabilities and deferred credits	(409		)		(362		)
	$	(406	)		$	(358	)

X

- References

No definition available.

+ Details

Name:	us-gaap_IncomeTaxDisclosureAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tabular disclosure of the components of income tax expense attributable to continuing operations for each year presented including, but not limited to: current tax expense (benefit), deferred tax expense (benefit), investment tax credits, government grants, the benefits of operating loss carryforwards, tax expense that results from allocating certain tax benefits either directly to contributed capital or to reduce goodwill or other noncurrent intangible assets of an acquired entity, adjustments of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity, and adjustments of the beginning-of-the-year balances of a valuation allowance because of a change in circumstances that causes a change in judgment about the realizability of the related deferred tax asset in future years.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319

+ Details

Name:	us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tabular disclosure of the components of net deferred tax asset or liability recognized in an entity's statement of financial position, including the following: the total of all deferred tax liabilities, the total of all deferred tax assets, the total valuation allowance recognized for deferred tax assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319

+ Details

Name:	us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tabular disclosure of the reconciliation using percentage or dollar amounts of the reported amount of income tax expense attributable to continuing operations for the year to the amount of income tax expense that would result from applying domestic federal statutory tax rates to pretax income from continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

+ Details

Name:	us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration