Annual report pursuant to Section 13 and 15(d)

Unsecured Revolving Credit Facility And Term Loans (Schedule Of Interest Rate On Outstanding Borrowings Payable) (Details)

v3.20.4
Unsecured Revolving Credit Facility And Term Loans (Schedule Of Interest Rate On Outstanding Borrowings Payable) (Details)
 12 Months Ended
Mar. 06, 2018
Dec. 31, 2020
2017 Term Loan [Member]    
Line of Credit Facility [Line Items]    
Interest Rate - Applicable Basis Points Above LIBOR 1.55%  
2016 Term Loan [Member]    
Line of Credit Facility [Line Items]    
Interest Rate - Applicable Basis Points Above LIBOR 1.55%  
No Ratings Or Less Than Baa3 [Member] | 2017 Term Loan [Member] | No Ratings Or Less Than BBB- [Member]    
Line of Credit Facility [Line Items]    
Unsecured Debt Ratings   No ratings or less than BBB-/Baa3
No Ratings Or Less Than Baa3 [Member] | 2016 Term Loan [Member] | No Ratings Or Less Than BBB- [Member]    
Line of Credit Facility [Line Items]    
Unsecured Debt Ratings   No ratings or less than BBB-/Baa3
Interest Rate - Applicable Basis Points Above LIBOR   1.85%
Baa3 [Member] | 2017 Term Loan [Member] | BBB- [Member]    
Line of Credit Facility [Line Items]    
Unsecured Debt Ratings   BBB- or Baa3 (interest rate based on Company's election through March 5, 2018)
Baa3 [Member] | 2016 Term Loan [Member] | BBB- [Member]    
Line of Credit Facility [Line Items]    
Unsecured Debt Ratings   BBB- or Baa3 (interest rate based on Company's election through March 5, 2018)
Interest Rate - Applicable Basis Points Above LIBOR   1.40%
Baa2 [Member] | 2017 Term Loan [Member] | BBB [Member]    
Line of Credit Facility [Line Items]    
Unsecured Debt Ratings   BBB or Baa2
Baa2 [Member] | 2016 Term Loan [Member] | BBB [Member]    
Line of Credit Facility [Line Items]    
Unsecured Debt Ratings   BBB or Baa2
Interest Rate - Applicable Basis Points Above LIBOR   1.15%
Baa1 [Member] | 2017 Term Loan [Member] | BBB+ [Member]    
Line of Credit Facility [Line Items]    
Unsecured Debt Ratings   BBB+ or Baa1
Baa1 [Member] | 2016 Term Loan [Member] | BBB+ [Member]    
Line of Credit Facility [Line Items]    
Unsecured Debt Ratings   BBB+ or Baa1
Interest Rate - Applicable Basis Points Above LIBOR   1.00%
A3 Or Higher [Member] | 2017 Term Loan [Member] | A- Or Higher [Member]    
Line of Credit Facility [Line Items]    
Unsecured Debt Ratings   A- or A3 or higher
A3 Or Higher [Member] | 2016 Term Loan [Member] | A- Or Higher [Member]    
Line of Credit Facility [Line Items]    
Unsecured Debt Ratings   A- or A3 or higher
Interest Rate - Applicable Basis Points Above LIBOR   0.90%
Base Rate [Member] | No Ratings Or Less Than Baa3 [Member] | 2016 Term Loan [Member] | No Ratings Or Less Than BBB- [Member]    
Line of Credit Facility [Line Items]    
Interest Rate - Applicable Basis Points Above LIBOR   0.85%
Base Rate [Member] | Baa3 [Member] | 2016 Term Loan [Member] | BBB- [Member]    
Line of Credit Facility [Line Items]    
Interest Rate - Applicable Basis Points Above LIBOR   0.40%
Base Rate [Member] | Baa2 [Member] | 2016 Term Loan [Member] | BBB [Member]    
Line of Credit Facility [Line Items]    
Interest Rate - Applicable Basis Points Above LIBOR   0.15%
Base Rate [Member] | Baa1 [Member] | 2016 Term Loan [Member] | BBB+ [Member]    
Line of Credit Facility [Line Items]    
Interest Rate - Applicable Basis Points Above LIBOR   0.00%
Base Rate [Member] | A3 Or Higher [Member] | 2016 Term Loan [Member] | A- Or Higher [Member]    
Line of Credit Facility [Line Items]    
Interest Rate - Applicable Basis Points Above LIBOR   0.00%