Annual report pursuant to Section 13 and 15(d)

Unsecured Revolving Credit Facility (Change In The Operating Partnership's Unsecured Debt Ratings) (Details)

v3.3.1.900
Unsecured Revolving Credit Facility (Change In The Operating Partnership's Unsecured Debt Ratings) (Details) - Unsecured Revolving Credit Facility [Member]
 12 Months Ended
Dec. 31, 2015
No Ratings Or Less Than Baa3 [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 1.70%
Facility Fee Basis Points 0.35%
Baa3 [Member] | BBB- [Member]  
Line of Credit Facility [Line Items]  
Unsecured Debt Ratings BBB- or Baa3 (current)
Interest Rate - Applicable Basis Points Above LIBOR 1.30%
Facility Fee Basis Points 0.30%
Baa2 [Member] | BBB [Member]  
Line of Credit Facility [Line Items]  
Unsecured Debt Ratings BBB or Baa2
Interest Rate - Applicable Basis Points Above LIBOR 1.10%
Facility Fee Basis Points 0.20%
Baa1 [Member] | BBB+ [Member]  
Line of Credit Facility [Line Items]  
Unsecured Debt Ratings BBB+ or Baa1
Interest Rate - Applicable Basis Points Above LIBOR 1.00%
Facility Fee Basis Points 0.15%
A3 Or Higher [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 0.925%
Facility Fee Basis Points 0.125%