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- Definition

Agreement Renewal, Term

+ References

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- Definition

Capital Leases, Fixed-Price Purchase

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- Definition

Capital Leases, Leased Interest, Percentage

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- Definition

Leases, Number

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- Definition

Long-Term Purchase Commitment, Energy Volume Required

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- Definition

Long-Term Purchase Commitment, Number Of Contracts

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- Definition

Long-Term Purchase Commitment, Percentage

+ References

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- Definition

Long-Term Purchase Commitment, Quantity Required

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- Definition

Share of plant output being purchased under a long-term contract to purchase electricity from a production plant constructed and financed by a public utility district, cooperative, or other organization.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 10.D)
-URI http://asc.fasb.org/extlink&oid=6499423&loc=d3e659339-123030

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- Definition

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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- Definition

Period covered by the long-term purchase commitment, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

+ References

No definition available.

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Commitments - Fiscal Year Maturity (Footnotes) (Details) CAD in Millions, $ in Millions	1 Months Ended	12 Months Ended
	Apr. 30, 2015 MW	Dec. 31, 2016 USD ($) GWh lease contract agreement_renewal MW	Dec. 31, 2016 CAD
Long-term Purchase Commitment [Line Items]
Agreement Renewal, Number \| agreement_renewal		10,000,000
Agreement Renewal, Term		50 years
UNS Energy Corporation \| Springerville Common Facilities
Long-term Purchase Commitment [Line Items]
Capital leases, undivided leased interest, percentage		32.20%
Fixed purchase price \| $		$ 68
Leases, Number \| lease		2
Power
Long-term Purchase Commitment [Line Items]
Purchase obligation			CAD 2,295
Power \| FortisOntario
Long-term Purchase Commitment [Line Items]
Purchase obligation			743
Power \| FortisOntario \| Maximum
Long-term Purchase Commitment [Line Items]
Amount of volume required (in mw) \| MW		145,000,000
Power \| FortisOntario \| Minimum
Long-term Purchase Commitment [Line Items]
Volume of energy required to be purchased (in GWh) \| GWh		537
Power \| FortisBC Energy
Long-term Purchase Commitment [Line Items]
Purchase obligation			486
Power \| FortisBC Electric
Long-term Purchase Commitment [Line Items]
Purchase obligation			288
Long-term renewable PPA, term		20 years
Amount of volume required (in mw) \| MW	234
Power \| FortisBC Electric \| Maximum
Long-term Purchase Commitment [Line Items]
Amount of volume required (in mw) \| MW		200
Volume of energy required to be purchased (in GWh) \| GWh		1,752
Power \| Maritime Electric
Long-term Purchase Commitment [Line Items]
Number of long-term take-or-pay contracts \| contract		2
Power \| Maritime Electric \| Nuclear Generating Station
Long-term Purchase Commitment [Line Items]
Share of plant output, percentage		4.55%
Power \| Payment guarantee \| Maritime Electric
Long-term Purchase Commitment [Line Items]
Purchase obligation			480
WECA \| FortisBC Electric
Long-term Purchase Commitment [Line Items]
Long-term renewable PPA, term	40 years
Renewable Power
Long-term Purchase Commitment [Line Items]
Purchase obligation			1,625
Renewable Power \| TEP and UNS Electric, Inc
Long-term Purchase Commitment [Line Items]
Purchase obligation \| $		$ 1,210
Purchase commitment, percentage		100.00%
Take-or-pay contract \| FortisOntario
Long-term Purchase Commitment [Line Items]
Amount of volume required (in mw) \| MW		145,000,000
Coal \| UNS Energy Corporation
Long-term Purchase Commitment [Line Items]
Purchase obligation \| $		$ 496
Gas Transportation Services \| UNS Energy Corporation
Long-term Purchase Commitment [Line Items]
Purchase obligation \| $		244
Transmission Services \| UNS Energy Corporation
Long-term Purchase Commitment [Line Items]
Purchase obligation \| $		113
Renewable Energy Credit
Long-term Purchase Commitment [Line Items]
Purchase obligation			CAD 154
Renewable Energy Credit \| UNS Energy Corporation
Long-term Purchase Commitment [Line Items]
Purchase obligation \| $		$ 107