v2.4.0.6

Fair value of financial instruments (Tables)

12 Months Ended

Dec. 31, 2012

Fair value of financial instruments

Schedule of estimated carrying values and fair values of financial instruments

		2012						2011
		Carrying Amount			Fair Value			Carrying Amount			Fair Value
Cash and cash equivalents		$	60,191		$	60,191		$	60,651		$	60,651
Restricted cash			28,618			28,618			21,412			21,412
Derivative assets current			9,456			9,456			10,411			10,411
Derivative assets non-current			11,115			11,115			22,003			22,003
Derivative liabilities current			33,038			33,038			20,592			20,592
Derivative liabilities non-current			118,070			118,070			33,170			33,170
Revolving credit facility and long-term debt, including current portion			1,647,341			1,701,811			1,483,858			1,462,474
Convertible debentures			424,246			416,677			189,563			207,888

Schedule of recurring measurements of fair value hierarchy of financial assets and liabilities

		December 31, 2012
		Level 1			Level 2			Level 3			Total
Assets:
Cash and cash equivalents		$	60,191		$	—		$	—		$	60,191
Restricted cash			28,618			—			—			28,618
Derivative instruments asset			—			20,571			—			20,571
Total		$	88,809		$	20,571		$	—		$	109,380
Liabilities:
Derivative instruments liability		$	—		$	151,108		$	—		$	151,108
Total		$	—		$	151,108		$	—		$	151,108
		December 31, 2011
		Level 1			Level 2			Level 3			Total
Assets:
Cash and cash equivalents		$	60,651		$	—		$	—		$	60,651
Restricted cash			21,412			—			—			21,412
Derivative instruments asset			—			32,414			—			32,414
Total		$	82,063		$	32,414		$	—		$	114,477
Liabilities:
Derivative instruments liability		$	—		$	53,762		$	—		$	53,762
Total		$	—		$	53,762		$	—		$	53,762

X

- Definition

Tabular disclosure of the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments, assets, and liabilities. Such certain disclosures about the financial instruments, assets, and liabilities include: (1) the fair value of the required items together with their carrying amounts (as appropriate) and (2) the methodology and assumptions used in developing such estimates of fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 107

-Paragraph 14

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 18

-Subparagraph c(2), d, e, f

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 107

-Paragraph 15

-Subparagraph b-d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 159

-Paragraph 19

-Subparagraph a, b, c(1), d(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Subparagraph a, c(1), c(2), c(3), d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 10: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 107

-Paragraph 10

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 11: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

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- Definition

Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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