Quarterly report pursuant to Section 13 or 15(d)

Debt (Details)

 v2.3.0.11
Debt (Details) (USD $)
 3 Months Ended 6 Months Ended
Jun. 30, 2011
Jun. 30, 2010
Jun. 30, 2011
Jun. 30, 2010
Dec. 31, 2010
Debt          
Carrying Value $ 2,299,416,000   $ 2,299,416,000   $ 2,323,681,000
Interest expense associated with amortization of discount     3,367,000 2,649,000  
Capitalized interest costs 4,300,000 4,200,000 8,600,000 8,100,000  
Mortgage and Other Secured Loans:
          
Debt          
Carrying Value 1,565,046,000   1,565,046,000   1,643,005,000
Fixed rate mortgage loans
          
Debt          
Carrying Value 1,063,369,000   1,063,369,000   1,173,358,000
Stated Interest Rates, low end of range (as a percent)     5.20%    
Stated Interest Rates, high end of range (as a percent)     7.87%    
Unamortized discount included in carrying value 2,800,000   2,800,000   3,200,000
Weighted average interest rate (as a percent) 6.01%   6.01%    
Fixed rate mortgage loan maturing 2034
          
Debt          
Carrying Value 4,500,000   4,500,000    
Revolving Construction Facility
          
Debt          
Maximum Availability 225,000,000   225,000,000    
Carrying Value 175,001,000   175,001,000   142,339,000
Description of variable rate basis     LIBOR    
Variable rate, spread low end of range (as a percent) 1.60%   1.60%    
Variable rate, spread high end of range (as a percent) 2.00%   2.00%    
Weighted average interest rate (as a percent) 1.95%   1.95%    
Variable rate secured loans
          
Debt          
Carrying Value 309,923,000   309,923,000   310,555,000
Description of variable rate basis     LIBOR    
Variable rate, spread low end of range (as a percent) 2.25%   2.25%    
Variable rate, spread high end of range (as a percent) 3.00%   3.00%    
Floor interest rates on certain of debt, low end of range (as a percent)     4.25%    
Floor interest rates on certain of debt, high end of range (as a percent)     5.50%    
Variable rate secured loan maturing in 2012 with one-year extension option. 221,400,000   221,400,000    
Extension option period (in years)     1    
Other construction loan facility
          
Debt          
Maximum Availability 23,400,000   23,400,000    
Carrying Value 16,753,000   16,753,000   16,753,000
Description of variable rate basis     LIBOR    
Variable rate, spread (as a percent) 2.75%   2.75%    
Interest rate on debt (as a percent) 2.95%   2.95%    
Revolving Credit Facility
          
Debt          
Maximum Availability 800,000,000   800,000,000    
Carrying Value 342,000,000   342,000,000   295,000,000
Description of variable rate basis     LIBOR    
Variable rate, spread low end of range (as a percent) 0.75%   0.75%    
Variable rate, spread high end of range (as a percent) 1.25%   1.25%    
Weighted average interest rate (as a percent) 1.14%   1.14%    
Extension option period (in years)     1    
Unsecured notes payable
          
Debt          
Carrying Value 4,995,000   4,995,000   1,947,000
Stated interest rate (as a percent) 0.00%   0.00%    
Unamortized discount included in carrying value 2,000,000   2,000,000   1,100,000
4.25% Exchangeable Senior Notes
          
Debt          
Carrying Value 225,539,000   225,539,000   223,846,000
Stated interest rate (as a percent) 4.25%   4.25%    
Unamortized discount included in carrying value 14,500,000   14,500,000   16,200,000
Exchange rate per $1000 principal amount (in common shares)     20.8145    
Convertible debt principal amount, basis for exchange 1,000   1,000    
Exchange price per common share based on exchange rate (in dollars per share) $ 48.04   $ 48.04    
Principal amount of debt 240,000,000   240,000,000    
Effective interest rate, including amortization of issuance costs (as a percent) 6.05%   6.05%    
Interest expense at stated interest rate 2,550,000 2,380,000 5,100,000 2,380,000  
Interest expense associated with amortization of discount 852,000 803,000 1,692,000 803,000  
Total interest expenses 3,402,000 3,183,000 6,792,000 3,183,000  
3.5% Exchangeable Senior Notes
          
Debt          
Carrying Value 161,836,000   161,836,000   159,883,000
Stated interest rate (as a percent) 3.50%   3.50%    
Unamortized discount included in carrying value 664,000   664,000   2,600,000
Exchange rate per $1000 principal amount (in common shares)     19.3470    
Convertible debt principal amount, basis for exchange 1,000   1,000    
Exchange price per common share based on exchange rate (in dollars per share) $ 51.69   $ 51.69    
Principal amount of debt 162,500,000   162,500,000    
Effective interest rate, including amortization of issuance costs (as a percent) 5.97%   5.97%    
Interest expense at stated interest rate 1,422,000 1,422,000 2,844,000 2,844,000  
Interest expense associated with amortization of discount 984,000 927,000 1,953,000 1,840,000  
Total interest expenses $ 2,406,000 $ 2,349,000 $ 4,797,000 $ 4,684,000