Income Taxes (Details) (USD $)	3 Months Ended
Mar. 31, 2015	Sep. 30, 2012	Dec. 31, 2014
Unrecognized Tax Benefits [Abstract]
Unrecognized tax benefit - Permanent tax positions	$ 1,500,000		$ 1,500,000
Unrecognized tax benefit - Temporary tax positions	12,300,000		11,700,000
Total unrecognized tax benefit	13,800,000us-gaap_UnrecognizedTaxBenefits		13,200,000us-gaap_UnrecognizedTaxBenefits
NOL and tax credit carryforwards	(5,500,000)		(4,800,000)
Upper bound of decrease in unrecognized tax benefit that is reasonably possible	(2,000,000)
Amounts accrued for penalties related to unrecognized tax benefits	0
Internal Revenue Service (IRS)
Tax Audits [Abstract]
Earliest year subject to examination	2009
Year(s) under examination		2010 and 2011
Year of carryback claim under examination		2009
Potential Tax Adjustments	$ 12,000,000
State Jurisdiction (Texas)
Tax Audits [Abstract]
Earliest year subject to examination	2009

The earliest open tax year(s) subject to income tax examination by a taxing authority.

No definition available.

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- Definition

The potential income tax expense that could become payable in the event of a successful challenge by a taxing authority of an entity's income tax position.

+ References

No definition available.

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- Definition

Tax benefits associated with NOL and tax credit carryforwards that reduce unrecognized tax benefits.

+ References

No definition available.

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- Definition

The tax year(s) being audited in connection with the income tax examination.

+ References

No definition available.

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- Definition

The total amount of unrecognized tax benefits for which the ultimate deductibility is highly certain but for which there is uncertainty about the timing of such deductibility and, if recognized, would not affect the effective tax rate but would accelerate the payment of cash to the taxing authority to an earlier period.

+ References

No definition available.

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- Definition

The tax year of a carryback claim under examination from a taxing authority.

+ References

No definition available.

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- Definition

Amount of (increase) decrease reasonably possible in the estimated upper bound of the unrecognized tax benefit for a tax position taken or expected to be taken.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

-Paragraph 15A

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- Definition

Amount of statutory penalties accrued for a tax position claimed or expected to be claimed by the entity, in its tax return.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)

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- Definition

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (b)

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