XML 52 R38.htm IDEA: XBRL DOCUMENT v3.19.1
Long-Term Debt and Common Stock (Details) - USD ($)
3 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Dec. 31, 2018
Debt Instrument [Abstract]      
Dividends Common Stock Declared Per Share $ 0.22    
Dividends Payable, Amount Per Share After Increase $ 0.2875    
Commercial Paper [Member]      
Line of Credit Facility [Line Items]      
Borrowings Outstanding $ 0   $ 0
Average Outstanding Amount   $ 18,000,000  
Weighted average interest rate (in hundredths)   1.76%  
Uncommitted Credit Facility [Member]      
Line of Credit Facility [Line Items]      
Borrowings Outstanding 0   0
Revolving Credit Agreement 2020 [Member]      
Line of Credit Facility [Line Items]      
Borrowings Outstanding 0   $ 0
Line of Credit Facility, Maximum Borrowing Capacity $ 2,000,000,000    
Line of Credit Facility, Expiration Date Jul. 21, 2020    
Maximum Total Debt To Total Capitalization Ratio Allowed Under Financial Covenant 65.00%    
Eurodollar [Member]      
Line of Credit Facility [Line Items]      
Weighted average interest rate (in hundredths) 3.50%    
Base Rate [Member]      
Line of Credit Facility [Line Items]      
Weighted average interest rate (in hundredths) 5.50%