XML 68 R13.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
Shareholders' Equity and Long-Term Incentive Compensation - Common Stock and Treasury Stock (Details) - $ / shares
 12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Summary of common shares issued, treasury shares and shares outstanding      
Balance at the beginning of the period (in shares) 43,450,305 42,651,000 41,940,000
Restricted stock shares and restricted stock units (in shares) 264,000 457,000 280,000
Retirement of treasury stock (in shares)     431,000
Other (in shares)   343,000  
Balance at the end of the period (in shares) 44,202,503 43,450,305 42,651,000
Common Stock      
Class of Stock [Line Items]      
Authorized shares (in shares) 200,000,000.0    
Par value (in dollars per share) $ 0.01    
Summary of common shares issued, treasury shares and shares outstanding      
Balance at the beginning of the period (in shares) 51,529,000 51,186,000 50,755,000
Restricted stock shares and restricted stock units (in shares) 0 0 0
Retirement of treasury stock (in shares)     431,000
Other (in shares) 488,000 343,000  
Balance at the end of the period (in shares) 52,017,000.000 51,529,000 51,186,000
Common Stock In Treasury      
Summary of common shares issued, treasury shares and shares outstanding      
Balance at the beginning of the period (in shares) (8,078,000.000) (8,535,000) (8,815,000)
Restricted stock shares and restricted stock units (in shares) 264,000 457,000 280,000
Retirement of treasury stock (in shares)     0
Other (in shares) 0 0  
Balance at the end of the period (in shares) (7,814,000) (8,078,000.000) (8,535,000)