Supplemental Disclosures of Cash Flow Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Supplemental Disclosures of Cash Flow Information [Abstract]
Cash paid for interest	$ 5,875	$ 3,368	$ 50,218	$ 29,820
Cash paid for income taxes	965		17,306	68
Noncash property changes	$ 10,325	$ 3,220	$ 46,182	$ 20,789

Increase in noncash property additions as relates to supplemental disclosures of cash flow information.

No definition available.

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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

+ 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=6367179&loc=d3e4297-108586

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3536-108585

+ Details

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- Definition

The amount of cash paid for interest during the period net of cash paid for interest that is capitalized.

+ References

+ Details

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- Details

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