v2.4.0.8

Long-term debt (Details) In Millions, unless otherwise specified																					0 Months Ended	1 Months Ended	9 Months Ended		0 Months Ended	9 Months Ended						1 Months Ended								0 Months Ended		0 Months Ended
	Sep. 30, 2013 USD ($)	Dec. 31, 2012 USD ($)	Sep. 30, 2013 Senior unsecured notes, due 2018 USD ($)	Dec. 31, 2012 Senior unsecured notes, due 2018 USD ($)	Sep. 30, 2013 Senior unsecured notes, due June 2036 USD ($)	Sep. 30, 2013 Senior unsecured notes, due June 2036 CAD	Dec. 31, 2012 Senior unsecured notes, due June 2036 USD ($)	Dec. 31, 2012 Senior unsecured notes, due June 2036 CAD	Sep. 30, 2013 Senior unsecured notes, due July 2014 USD ($)	Dec. 31, 2012 Senior unsecured notes, due July 2014 USD ($)	Sep. 30, 2013 Series A senior unsecured notes, due August 2015 USD ($)	Dec. 31, 2012 Series A senior unsecured notes, due August 2015 USD ($)	Sep. 30, 2013 Series B senior unsecured notes, due August 2017 USD ($)	Dec. 31, 2012 Series B senior unsecured notes, due August 2017 USD ($)	Sep. 30, 2013 Epsilon Power Partners term facility, due 2019 USD ($)	Dec. 31, 2012 Epsilon Power Partners term facility, due 2019 USD ($)	Sep. 30, 2013 Cadillac term loan, due 2025 USD ($)	Dec. 31, 2012 Cadillac term loan, due 2025 USD ($)	Sep. 30, 2013 Cadillac term loan, due 2025 Minimum	Sep. 30, 2013 Cadillac term loan, due 2025 Maximum	Apr. 19, 2013 Piedmont bridge loan, due 2013	Jul. 31, 2013 Piedmont bridge loan, due 2013 USD ($)	Sep. 30, 2013 Piedmont bridge loan, due 2013 USD ($)	Dec. 31, 2012 Piedmont bridge loan, due 2013 USD ($)	Aug. 02, 2013 Senior credit facility	Sep. 30, 2013 Senior credit facility USD ($)	Sep. 30, 2013 Meadow Creek term loan, due 2024 USD ($)	Dec. 31, 2012 Meadow Creek term loan, due 2024 USD ($)	Sep. 30, 2013 Meadow Creek term loan, due 2024 Minimum	Sep. 30, 2013 Meadow Creek term loan, due 2024 Maximum	Sep. 30, 2013 Construction loan USD ($)	Apr. 30, 2013 Cash grant loan USD ($)	Sep. 30, 2013 Cash grant loan USD ($)	Sep. 30, 2013 Rockland term loan, due 2027 USD ($)	Dec. 31, 2012 Rockland term loan, due 2027 USD ($)	Sep. 30, 2013 Other long-term debt USD ($)	Dec. 31, 2012 Other long-term debt USD ($)	Sep. 30, 2013 Other long-term debt Minimum	Sep. 30, 2013 Other long-term debt Maximum	Aug. 02, 2013 Amended senior credit facility USD ($)	Jul. 31, 2013 Amended senior credit facility USD ($)	Aug. 02, 2013 Amended senior credit facility US Prime Rate	Aug. 02, 2013 Amended senior credit facility Eurocurrency LIBOR Rate	Aug. 02, 2013 Amended senior credit facility Cdn. Prime Rate	Aug. 02, 2013 Amended senior credit facility Minimum USD ($)	Aug. 02, 2013 Amended senior credit facility Minimum US Prime Rate	Aug. 02, 2013 Amended senior credit facility Minimum Eurocurrency LIBOR Rate	Aug. 02, 2013 Amended senior credit facility Minimum Cdn. Prime Rate	Aug. 02, 2013 Amended senior credit facility Maximum	Aug. 02, 2013 Amended senior credit facility Maximum US Prime Rate	Aug. 02, 2013 Amended senior credit facility Maximum Eurocurrency LIBOR Rate	Aug. 02, 2013 Amended senior credit facility Maximum Cdn. Prime Rate
Long-term debt
Total debt			$ 460.0	$ 460.0	$ 203.8	210.0	$ 211.1	210.0	$ 190.0	$ 190.0	$ 150.0	$ 150.0	$ 75.0	$ 75.0	$ 31.2	$ 33.5	$ 36.0	$ 37.8					$ 76.6	$ 127.4			$ 171.4	$ 208.7			$ 171.4		$ 56.5	$ 85.8	$ 86.5	$ 1.0	$ 0.3
Less current maturities	(206.7)	(121.2)							190.0						4.5	3.0	2.1	2.4					4.4	55.1			4.1	59.5						1.4	1.2	0.2
Total long-term debt	1,274.1	1,459.1
Interest rate (as a percent)			9.00%		6.00%	6.00%			5.90%		5.90%		6.00%		7.40%				6.00%	8.00%									2.90%	5.10%				6.40%				5.50%	6.70%
Variable interest rate basis																							Libor			LIBOR																US Prime Rate	Eurocurrency LIBOR Rate	Cdn. Prime Rate
Amount drawn on the senior credit facility																										25.0
Letters of credit issued but not drawn																										91.2
Applicable margin (as a percent)																							3.50%			4.25%																				2.75%	2.75%	2.75%		4.75%	4.75%	4.75%
Bridge loan																							51.0
Recovery as a percentage of capital cost																					30.00%
Construction loan																							82.0
Amount received under the 1603 federal grant program																						49.5
Repayment of debt from proceeds from 1603 grant with U.S. Treasury																						51.0										49.0
Maximum borrowing capacity																										150.0														150.0	300.0
Maximum capacity to be utilized for letter of credit																																								200
Contribution to cover shortfall resulting from the federal sequester on spending																						1.5										4.7
Aggregate amount of sublimit available for borrowings																																								25
Cash collateralized required if letters of credit and borrowings outstanding under the amended credit facility exceeds $125 million																																													125
Threshold limit of amended credit facility for required cash collateralized																																													125
Unrestricted cash and cash equivalents																																													75
Consolidated Total Net Debt to Consolidated EBITDA																									7.50																								7.75
Consolidated EBITDA to Consolidated Interest Expense																									2.25																				1.60
Commitment fee (as a percent)																									1.50%																				0.75%				1.75%
Consolidated Total Net Debt to Consolidated EBITDA Over Time																									700.00%
Period preceding the maturity of debt for voluntarily prepayment or repurchase of any outstanding debt																																								60 days
Contribution to cover shortfall resulting from lower grant-eligible costs																																$ 2.8

X

- Definition

Represents the amount of contribution made to cover shortfall resulting from the federal sequester on spending.

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Represents the amount of contribution made to cover shortfall resulting from lower grant-eligible costs.

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- Definition

Represents the ratio of consolidated adjusted earnings before interest, taxes, depreciation and amortization to interest expense required to be maintained under the terms of the debt covenants.

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Represents the ratio of consolidated total debt to consolidated adjusted earnings before, interest, taxes, depreciation and amortization allowed under the terms of the debt covenants.

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Represents the ratio of consolidated total debt to consolidated adjusted earnings before, interest, taxes, depreciation and amortization allowed under the terms of the debt covenants over time.

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Represents the period preceding the maturity of debt that can be used for voluntarily prepayment or repurchase of any outstanding debt of the entity under the terms of the debt covenants.

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Represents the amount of unrestricted cash and cash equivalents to be maintained under the terms of the debt covenants.

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No definition available.

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Represents the amount of cash collateralized required if letters of credit and borrowings outstanding under the amended credit facility exceeds specified limit.

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Represents the sublimit amount of borrowing capacity available for borrowing under a line of credit facility.

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Represents the threshold limit of amended credit facility for required cash collateralized.

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The cash inflow from government grants during the period.

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Represents the recovery as a percentage of capital cost under 1603 federal grant program.

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- Definition

Short-Term financing which is expected to be paid back relatively quickly, such as by a subsequent longer-term loan. Also called swing loan or bridge financing.

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This element represents the carrying value of a short-term real estate loan to finance building costs. The funds are disbursed as needed or in accordance with a prearranged plan; generally, a portion of the funds is disbursed at inception and the remainder as construction progresses. The money is repaid on completion of the project, usually from the proceeds of a mortgage loan. The rate is normally higher than the prime rate, and there is usually an origination fee. The effective yield on these loans tends to be high, and the lender has a security interest in the real property. Note that there are separate concepts for the current and noncurrent portions of long-term construction loans.

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

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The reference rate for the variable rate of the 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.

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

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Face (par) amount of the original debt instrument that was repurchased.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Amount borrowed under the credit facility as of the balance sheet date.

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The maximum amount of borrowing capacity under a line of credit that is available as of the balance sheet date for a specific purpose other than for financing goods acquired for inventory or imminent delivery to a customer.

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- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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No definition available.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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