The amount of debt that was repriced on the effective date.

No definition available.

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- Definition

Represents the minimum reference rate for variable rate of debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

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- Definition

Period of time between original maturity and revised maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, mortgage loans and commercial paper. Excludes capital lease obligations and debentures.

+ References

No definition available.

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- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, mortgage loans and commercial paper. Excludes capital lease obligations and debentures.

+ References

No definition available.

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- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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-Name Accounting Standards Codification
-Topic 942
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

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-Topic 835
-SubTopic 30
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-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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- Definition

Incremental percentage increase (decrease) in the stated rate on a debt instrument.

+ References

No definition available.

+ Details

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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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.

+ References

No definition available.

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- Definition

Amount, after accumulated amortization, of debt discount.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28541-108399

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-SubTopic 30
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-Paragraph 8
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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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- Definition

Amount of cash paid for interest. Includes, but is not limited to, payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586

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-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

+ Details

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- Definition

Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

+ Details

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Period Type:	instant

- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Long-term debt (Details) CAD in Millions, $ in Millions				9 Months Ended
Long-term debt (Details) CAD in Millions, $ in Millions	Oct. 28, 2017	Oct. 18, 2017 USD ($)	Oct. 13, 2017 USD ($)	Sep. 30, 2017 CAD	Oct. 30, 2017 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)
Long-term debt
Less: unamortized discount						$ (13.8)	$ (17.2)
Less: unamortized deferred financing costs						(11.6)	(15.3)
Less: current maturities						(156.5)	(111.9)
Less: current maturities						(156.5)	(111.9)
Total long-term debt						637.3	749.2
New term loan facility
Long-term debt
Length of extension to term of credit facility	1 year
Senior secured term loan facility, due 2023
Long-term debt
Long-term Debt, Gross						562.7	639.9
Less: current maturities						(92.5)	(100.0)
Applicable margin (as a percent)				4.25%
Senior unsecured notes, due June 2036 (Cdn$210.0)
Long-term debt
Long-term Debt, Gross						$ 168.3	156.4
Face amount of debt \| CAD				CAD 210.0
Interest rate (as a percent)				5.95%		5.95%
Epsilon Power Partners term facility, due 2019
Long-term debt
Long-term Debt, Gross						$ 8.8	13.5
Less: current maturities						(6.4)	(6.2)
Cadillac term loan, due 2025
Long-term debt
Long-term Debt, Gross						24.8	27.0
Less: current maturities						(3.0)	(3.0)
Piedmont term loan, due 2018
Long-term debt
Long-term Debt, Gross						54.6	56.6
Less: current maturities						(54.6)	(2.5)
Applicable margin (as a percent)				3.75%
Other long-term debt
Long-term debt
Long-term Debt, Gross							0.2
Less: current maturities							(0.2)
Interest rate swaps
Long-term debt
Notional amount						434.6	$ 506.9
Interest rate swaps \| New term loan facility
Long-term debt
Notional amount						$ 354.0
Forecast
Long-term debt
Interest rate margin reduction		(0.75%)
Applicable margin (as a percent)		3.50%
Forecast \| New term loan facility
Long-term debt
Face amount of debt					$ 200.0
Amount of debt repriced		$ 562.7
Forecast \| Piedmont term loan, due 2018
Long-term debt
Extinguishment of Debt, Amount			$ 54.6
Interest Paid			0.1
Payment to terminate interest rate swap agreements			9.4
Write-off of deferred financing costs			$ 0.9
Minimum \| Other long-term debt
Long-term debt
Interest rate (as a percent)				5.50%		5.50%
Maximum \| Other long-term debt
Long-term debt
Interest rate (as a percent)				6.70%		6.70%
London Interbank Offered Rate (LIBOR) \| Epsilon Power Partners term facility, due 2019
Long-term debt
Applicable margin (as a percent)				3.13%
London Interbank Offered Rate (LIBOR) \| Cadillac term loan, due 2025
Long-term debt
Applicable margin (as a percent)				1.37%
Long-term debt excluding debentures \| London Interbank Offered Rate (LIBOR) \| New term loan facility
Long-term debt
Minimum percentage of variable rate base				1.00%