XML 43 R32.htm IDEA: XBRL DOCUMENT v3.8.0.1
Senior Notes (Details) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2017
Sep. 30, 2017
Dec. 31, 2016
Sep. 24, 2016
Debt Instrument [Line Items]          
Senior Notes $ 150 $ 150 $ 150 $ 0 $ 0
Senior Notes, Maturity Date Aug. 14, 2029        
Senior Notes, Interest Rate 3.70% 3.70% 3.70%    
Shelf Note - Amount $ 150 $ 150 $ 150    
Shelf Notes - Maximum Maturity Date Range - in years 12        
Shelf Notes - Maximum Issuance Date August 14, 2020        
Debt Instrument, Percentage of Principal Amount Redeemable 1        
Shelf Notes - Additional Interest Rate 0.005        
Debt Instrument, Covenant Compliance all        
Amount of incremental credit facility which will result in modification of debt covenants     100    
Number of Financial Covenants [Member]          
Debt Instrument [Line Items]          
Debt Instrument, Covenant Description   2      
Fixed Charge Coverage Ratio Minimum Requirement [Member]          
Debt Instrument [Line Items]          
Debt Instrument, Covenant Description   2.00      
Leverage Ratio Maximum Requirement [Member]          
Debt Instrument [Line Items]          
Debt Instrument, Covenant Description   4.00