Income Taxes	9 Months Ended
Sep. 30, 2017
Income Tax Disclosure [Abstract]
Income Taxes	The Company has adopted the provisions of ASU 2016-09 as of January 1, 2017 which requires recognition through opening retained earnings of any pre-adoption date net operating loss (“NOL”) carryforwards from nonqualified stock options and other employee share-based payments (e.g., restricted shares and share appreciation rights), as well as recognition of all income tax effects from share-based payments arising on or after January 1, 2017 in income tax expense. As a result, the Company has recognized through opening retained earnings $18.4 million of pre-adoption date NOL carryforwards with remaining carryforward periods of at least seven years (the corresponding deferred tax asset is $6.5 million). No valuation allowance is needed as the newly recognized NOL is considered more likely than not realizable given that it has sufficient positive sources of taxable income including continued profitability and utilization of NOLs, taxable reversing temporary differences and reliable forecast of income. On an interim basis, the Company estimates what its anticipated annual effective tax rate will be and records a quarterly income tax provision in accordance with the estimated annual rate, plus the tax effect of certain discrete items that arise during the quarter. As the fiscal year progresses, the Company refines its estimates based on actual events and financial results during the year. This process can result in significant changes to the Company’s estimated effective tax rate. When this occurs, the income tax provision is adjusted during the quarter in which the estimates are refined so that the year-to-date provision reflects the estimated annual effective tax rate. These changes, along with adjustments to the Company's deferred taxes and related valuation allowance, may create fluctuations in the overall effective tax rate from quarter to quarter. The Company’s effective tax rate for the three and nine months ended September 30, 2017 differed from the U.S. federal statutory rate primarily due to state income taxes and tax deficiencies from stock-based compensation. The total amount of unrecognized tax benefits, excluding associated interest and penalties, was $0.5 million as of September 30, 2017, all of which, if subsequently recognized, would have affected the Company’s tax rate. As of September 30, 2017 and December 31, 2016, the total balance of accrued interest and penalties related to uncertain tax positions was zero. The Company recognizes interest and penalties related to uncertain tax positions as a component of income tax expense, and the accrued interest and penalties are included in deferred and other long-term liabilities in the Company’s condensed consolidated balance sheets. There were no material interest or penalties included in income tax expense for the three and nine months ended September 30, 2017 and September 30, 2016. The Company is subject to taxation in the U.S. and in various foreign and state jurisdictions. Due to expired statutes of limitation, the Company’s federal income tax returns for years prior to calendar year 2014 are not subject to examination by the U.S. Internal Revenue Service. Generally, for the majority of state jurisdictions where the Company does business, periods prior to calendar year 2013 are no longer subject to examination. The Company does not anticipate a significant change to the total amount of unrecognized tax benefits within the next twelve months. Audit outcomes and the timing of settlements are subject to significant uncertainty.

Income Taxes

9 Months Ended

Sep. 30, 2017

The Company has adopted the provisions of ASU 2016-09 as of January 1, 2017 which requires recognition through opening retained earnings of any pre-adoption date net operating loss (“NOL”) carryforwards from nonqualified stock options and other employee share-based payments (e.g., restricted shares and share appreciation rights), as well as recognition of all income tax effects from share-based payments arising on or after January 1, 2017 in income tax expense. As a result, the Company has recognized through opening retained earnings $18.4 million of pre-adoption date NOL carryforwards with remaining carryforward periods of at least seven years (the corresponding deferred tax asset is $6.5 million). No valuation allowance is needed as the newly recognized NOL is considered more likely than not realizable given that it has sufficient positive sources of taxable income including continued profitability and utilization of NOLs, taxable reversing temporary differences and reliable forecast of income.

On an interim basis, the Company estimates what its anticipated annual effective tax rate will be and records a quarterly income tax provision in accordance with the estimated annual rate, plus the tax effect of certain discrete items that arise during the quarter. As the fiscal year progresses, the Company refines its estimates based on actual events and financial results during the year. This process can result in significant changes to the Company’s estimated effective tax rate. When this occurs, the income tax provision is adjusted during the quarter in which the estimates are refined so that the year-to-date provision reflects the estimated annual effective tax rate. These changes, along with adjustments to the Company's deferred taxes and related valuation allowance, may create fluctuations in the overall effective tax rate from quarter to quarter.

The Company’s effective tax rate for the three and nine months ended September 30, 2017 differed from the U.S. federal statutory rate primarily due to state income taxes and tax deficiencies from stock-based compensation.

The total amount of unrecognized tax benefits, excluding associated interest and penalties, was $0.5 million as of September 30, 2017, all of which, if subsequently recognized, would have affected the Company’s tax rate.

As of September 30, 2017 and December 31, 2016, the total balance of accrued interest and penalties related to uncertain tax positions was zero. The Company recognizes interest and penalties related to uncertain tax positions as a component of income tax expense, and the accrued interest and penalties are included in deferred and other long-term liabilities in the Company’s condensed consolidated balance sheets. There were no material interest or penalties included in income tax expense for the three and nine months ended September 30, 2017 and September 30, 2016.

The Company is subject to taxation in the U.S. and in various foreign and state jurisdictions. Due to expired statutes of limitation, the Company’s federal income tax returns for years prior to calendar year 2014 are not subject to examination by the U.S. Internal Revenue Service. Generally, for the majority of state jurisdictions where the Company does business, periods prior to calendar year 2013 are no longer subject to examination. The Company does not anticipate a significant change to the total amount of unrecognized tax benefits within the next twelve months. Audit outcomes and the timing of settlements are subject to significant uncertainty.