Equity-Based Compensation Plans Equity Based Compensation Plans (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2013	Dec. 31, 2012
Performance Cash Award 2012 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite Service Period		3 years
Percent allocated to performance year one	50.00%
Percent allocated to performance year two	0.00%
Percent allocated to performance year three	50.00%
Performance percent target achieved year one		85.00%
Performance cash:
Beginning Balance	$ 1,293,687
Long-term incentives, settled in cash, earned	314,909
Long-term Incentives, settled in cash, issued	0
Ending Balance	1,608,596	1,293,687
Performance Cash Award 2012 [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement by Share Based Payment Award Equity Instrument Other Than Option Stock Issuance Percentage Multiplier		0.00%
Performance Cash Award 2012 [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement by Share Based Payment Award Equity Instrument Other Than Option Stock Issuance Percentage Multiplier		200.00%
Performance Cash Award 2013 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite Service Period	3 years
Percent allocated to performance year one	50.00%
Percent allocated to performance year two	0.00%
Percent allocated to performance year three	50.00%
Performance cash:
Beginning Balance	0
Long-term incentives, settled in cash, earned	360,099
Long-term Incentives, settled in cash, issued	0
Ending Balance	$ 360,099
Performance Cash Award 2013 [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement by Share Based Payment Award Equity Instrument Other Than Option Stock Issuance Percentage Multiplier	0.00%
Performance Cash Award 2013 [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement by Share Based Payment Award Equity Instrument Other Than Option Stock Issuance Percentage Multiplier	200.00%

Long-Term Incentive Award, Settled in Cash

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- Definition

long-term incentive, settled in cash, earned

+ References

No definition available.

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- Definition

Long-Term Incentives, Settled in Cash, Issued

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award equity instrument other than option stock award percent allocated to performance year one

+ References

No definition available.

+ Details

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- Definition

Share based compensation arrangement by share based payment award equity instrument other than option stock award percent allocated to performance year three

+ References

No definition available.

+ Details

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- Definition

Share based compensation arrangement by share based payment award equity instrument other than option stock award percent allocated to performance year two

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award equity instrument other than option stock issuance percentage multiplier.

+ References

No definition available.

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- Definition

Share based compensation by share based payment award quity instrument other than stock award percent target achieved year one

+ References

No definition available.

+ Details

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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