Income Taxes	6 Months Ended
Jun. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	12. Income Taxes The Company’s effective income tax rate fluctuates from the U.S. statutory tax rate based on, among other factors, changes in pretax income in countries with varying statutory tax rates, impact of state and local taxes, and other differences related to the recognition of income and expense between U.S. GAAP and tax. The Company’s effective income tax rate for the three months ended June 30, 2018 was 43.9%, compared with 37.9% for the three months ended June 30, 2017. The higher effective income tax rate for the three months ended June 30, 2018 was primarily attributable to changes in forecasted annual pretax income from the first quarter of 2018 to the second quarter of 2018. The Company’s effective income tax rate for the six months ended June 30, 2018 was 15.2%, compared with 37.5% for the six months ended June 30, 2017. The lower effective income tax rate for the six months ended June 30, 2018 was primarily attributable to the reduction to the U.S. federal statutory tax rate and additional limitations for the deductibility of meals and entertainment expenses as a result of Tax Reform. The Company also recorded a valuation allowance against the net deferred tax assets of a certain Canadian subsidiary of the Company due to a change in judgment as to the realizability of these assets in the first quarter of 2018. The Company recognized the income tax effects of Tax Reform in its audited financial statements included in the Company’s 2017 Annual Report on Form 10-K in accordance with Staff Accounting Bulletin No. 118, which provides SEC staff guidance for the application of ASC Topic 740, Income Taxes, in the reporting period during which Tax Reform was signed into law. The guidance also provides for a measurement period of up to one year from the enactment date of Tax Reform for the Company to complete its accounting for the U.S. tax law changes. As such, the Company’s 2017 financial results reflected the provisional estimate of the income tax effects of the Tax Reform. This continues to represent a provisional estimate of the impact of Tax Reform. The estimate of the impact of Tax Reform was based on certain assumptions and the Company’s current interpretation of Tax Reform. This estimate may change as the Company receives additional clarification and implementation guidance and as additional interpretations of Tax Reform become available.

12. Income Taxes

The Company’s effective income tax rate fluctuates from the U.S. statutory tax rate based on, among other factors, changes in pretax income in countries with varying statutory tax rates, impact of state and local taxes, and other differences related to the recognition of income and expense between U.S. GAAP and tax.

The Company’s effective income tax rate for the three months ended June 30, 2018 was 43.9%, compared with 37.9% for the three months ended June 30, 2017. The higher effective income tax rate for the three months ended June 30, 2018 was primarily attributable to changes in forecasted annual pretax income from the first quarter of 2018 to the second quarter of 2018.

The Company’s effective income tax rate for the six months ended June 30, 2018 was 15.2%, compared with 37.5% for the six months ended June 30, 2017. The lower effective income tax rate for the six months ended June 30, 2018 was primarily attributable to the reduction to the U.S. federal statutory tax rate and additional limitations for the deductibility of meals and entertainment expenses as a result of Tax Reform. The Company also recorded a valuation allowance against the net deferred tax assets of a certain Canadian subsidiary of the Company due to a change in judgment as to the realizability of these assets in the first quarter of 2018.

The Company recognized the income tax effects of Tax Reform in its audited financial statements included in the Company’s 2017 Annual Report on Form 10-K in accordance with Staff Accounting Bulletin No. 118, which provides SEC staff guidance for the application of ASC Topic 740, Income Taxes, in the reporting period during which Tax Reform was signed into law. The guidance also provides for a measurement period of up to one year from the enactment date of Tax Reform for the Company to complete its accounting for the U.S. tax law changes. As such, the Company’s 2017 financial results reflected the provisional estimate of the income tax effects of the Tax Reform. This continues to represent a provisional estimate of the impact of Tax Reform. The estimate of the impact of Tax Reform was based on certain assumptions and the Company’s current interpretation of Tax Reform. This estimate may change as the Company receives additional clarification and implementation guidance and as additional interpretations of Tax Reform become available.