Income Taxes Level 1 (Notes)	9 Months Ended
Income Taxes Level 1 (Notes)	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Income Tax Disclosure	Income Taxes Income tax expense during interim periods is based on our estimated annual effective income tax rate plus any discrete items, which are recorded in the period in which they occur. Discrete items include, among others, such events as changes in estimates due to the finalization of tax returns, tax audit settlements, expiration of statutes of limitation, and increases or decreases in valuation allowances on deferred tax assets. Our effective tax rate was 22.7% and 2.7% for the three months ended September 30, 2020 and 2019, respectively. Our effective tax rate was 23.6% and 17.3% for the nine months ended September 30, 2020 and 2019, respectively. The lower effective tax rate for the three and nine months ended September 30, 2019 was primarily due to the reduction in tax liability as a result of the expiration of statutes of limitation and higher excess tax benefits on the settlement of employee share-based awards. Unrecognized Tax Benefits As of September 30, 2020, the total amount of our unrecognized tax benefits was $1.3 million and the total amount of our accrued interest was $0.7 million. The federal statutes of limitation have expired for all tax years prior to 2017, and we are not currently under audit by the IRS. Various state jurisdictions are auditing years 2013 through 2018. There are currently no federal or provincial audits in Canada; however, years subsequent to 2015 remain open and could be subject to examination. It is reasonably possible that the amount of unrecognized tax benefits may change within the next twelve months. However, given the number of years that remain subject to examination and the number of matters being examined, an estimate of the range of the possible increase or decrease cannot be made.

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.