XML 54 R43.htm IDEA: XBRL DOCUMENT v3.8.0.1
Stockholders' Equity - Scheduled Vesting for Outstanding Restricted Stock Units (Details) - Restricted Stock Units - shares
shares in Millions
Mar. 31, 2018
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Nine Months Ended December 31, 2018 6.0  
Year Ended December 31, 2019 7.2  
Year Ended December 31, 2020 3.7  
Year Ended December 31, 2021 1.8  
Year Ended December 31, 2022 0.2  
Thereafter 0.2  
Total 19.1 20.1