XML 83 R81.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
Long-Term Debt (Narrative) (Details)
1 Months Ended 12 Months Ended
Jan. 31, 2019
USD ($)
Dec. 31, 2019
USD ($)
type_of_borrowing
business_day
lender
Dec. 31, 2018
USD ($)
Short-term Debt [Line Items]      
Maximum borrowing capacity   $ 1,200,000,000.0 $ 800,000,000.0
Long-term debt $ 12,500,000    
Number of lenders in syndicate | lender   13  
Credit facility outstanding   $ 61,500,000 70,000,000.0
Number of types of borrowing that may be elected under the facility | type_of_borrowing   4  
Number of business days' notice to terminate facility | business_day   3  
Letters of credit      
Short-term Debt [Line Items]      
Maximum borrowing capacity   $ 125,000,000.0  
Term Loan Facility      
Short-term Debt [Line Items]      
Maturities (term) 5 years    
Long-term debt $ 500,000,000.0    
Leverage ratio, max   425.00%  
Leverage ratio, minimum   350.00%  
Percentage of total assets   15.00%  
Revolving credit facility      
Short-term Debt [Line Items]      
Maximum borrowing capacity $ 1,200,000,000.0   $ 800,000,000.0
Letters of credit      
Short-term Debt [Line Items]      
Credit facility outstanding   $ 0