Compensation Related Costs, Share Based Payments	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Share-based Payment Arrangement	We have stock award plans for key employees and directors, pursuant to which awards of stock options, SSARs, restricted stock, restricted stock units, and performance stock units (PSUs) are granted. In addition, we offer an employee stock purchase plan to employees.In July 2021, LP modified the performance vesting criteria of approximately 149,000 PSU awards granted in 2020. The modification was considered a Type III modification under the Accounting for Share-Based Payments (Topic 718), in which the original awards were canceled, and the modified awards were considered granted on the modification date. Post-modification stock-based compensation expense related to these awards will be recognized over the remaining service period using modification date fair values of between $56.35 and $64.12 and the number of awards expected to vest. We recognized $5 million in stock-based compensation expense during the three months ended September 30, 2021, and 2020. We recognized $10 million and $8 million in stock-based compensation expense during the nine months ended September 30, 2021, and 2020, respectively. At September 30, 2021, there was $34 million of unrecognized stock-based compensation expense related to unvested PSUs, restricted stock units, and SSARs attributable to future service.