Income Taxes	3 Months Ended
Mar. 31, 2014
Income Tax Disclosure [Abstract]
Income Taxes	9. INCOME TAXES As of December 31, 2013, the Company determined that it more likely than not will realize most of its deferred tax assets and, as a result, reversed a significant portion of its valuation allowance. As of March 31, 2014, the Company has a valuation allowance of $4.2 million, primarily related to certain state tax credits the Company estimates will expire before they are realized. The Company analyzes its position in each reporting period, considering all available positive and negative evidence, in determining the expected realization of its deferred tax assets. The Company’s effective tax rate for the three months ended March 31, 2014 and 2013 was 37.3% and 0.9% respectively, which resulted in expense of $7.3 million and $0.2 million, respectively. The lower effective tax rate for the three months ended March 31, 2013 was a direct result of the Company maintaining a full valuation allowance against its deferred tax assets. During the three months ended March 31, 2014, the Company realized $6.5 million of excess tax benefits from stock-based awards and, accordingly, recorded an increase to additional paid-in capital. The Company operates in multiple tax jurisdictions and, in the normal course of business, its tax returns are subject to examination by various taxing authorities. Such examinations may result in future assessments by these taxing authorities, and the Company accrues a liability when it believes that it is more likely than not that benefits of tax positions will not be realized. The Company believes that adequate provisions have been made for all tax returns subject to examination. As of March 31, 2014, federal tax years 2010 through 2013 remain subject to examination, while tax returns in certain state tax jurisdictions for years 2008 through 2013 remain subject to examination. The Company’s returns filed with the state of Michigan for tax years 2008 through 2011 are currently under examination. No material adjustments are expected as a result of the audit. In September 2013, the Internal Revenue Service issued Treasury Decision 9636, which enacted final tax regulations regarding the capitalization and expensing of amounts paid to acquire, produce, or improve tangible property. The regulations also include guidance regarding the retirement of depreciable property. The Company has assessed the impact of the final regulations on its financial statements and does not expect any material adjustments or changes.

9. INCOME TAXES

As of December 31, 2013, the Company determined that it more likely than not will realize most of its deferred tax assets and, as a result, reversed a significant portion of its valuation allowance. As of March 31, 2014, the Company has a valuation allowance of $4.2 million, primarily related to certain state tax credits the Company estimates will expire before they are realized. The Company analyzes its position in each reporting period, considering all available positive and negative evidence, in determining the expected realization of its deferred tax assets.

The Company’s effective tax rate for the three months ended March 31, 2014 and 2013 was 37.3% and 0.9% respectively, which resulted in expense of $7.3 million and $0.2 million, respectively. The lower effective tax rate for the three months ended March 31, 2013 was a direct result of the Company maintaining a full valuation allowance against its deferred tax assets.

During the three months ended March 31, 2014, the Company realized $6.5 million of excess tax benefits from stock-based awards and, accordingly, recorded an increase to additional paid-in capital.

The Company operates in multiple tax jurisdictions and, in the normal course of business, its tax returns are subject to examination by various taxing authorities. Such examinations may result in future assessments by these taxing authorities, and the Company accrues a liability when it believes that it is more likely than not that benefits of tax positions will not be realized. The Company believes that adequate provisions have been made for all tax returns subject to examination. As of March 31, 2014, federal tax years 2010 through 2013 remain subject to examination, while tax returns in certain state tax jurisdictions for years 2008 through 2013 remain subject to examination. The Company’s returns filed with the state of Michigan for tax years 2008 through 2011 are currently under examination. No material adjustments are expected as a result of the audit.

In September 2013, the Internal Revenue Service issued Treasury Decision 9636, which enacted final tax regulations regarding the capitalization and expensing of amounts paid to acquire, produce, or improve tangible property. The regulations also include guidance regarding the retirement of depreciable property. The Company has assessed the impact of the final regulations on its financial statements and does not expect any material adjustments or changes.