|
Credit Risk and Fair Value of Financial Instruments Level 4 (Details) (USD $)
In Thousands, unless otherwise specified
|
Dec. 31, 2011
|
Dec. 31, 2010
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
| Bank credit facility due March 2016 |
$ 65,000 |
$ 0 |
| Mortgage notes and other debt, maturities through 2047 |
36,340 |
37,991 |
| Total fair value of debt instruments |
1,895,423 |
1,789,056 |
|
February 2013 [Member]
|
|
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
| Senior Notes |
4,971 |
9,092 |
|
October 2014 [Member]
|
|
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
| Senior Notes |
196,954 |
194,244 |
|
April 2015 [Member]
|
|
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
| Senior Notes |
150,083 |
161,968 |
|
April 2016 [Member]
|
|
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
| Senior Notes |
216,375 |
216,653 |
|
June 2017 [Member]
|
|
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
| Senior Notes |
323,025 |
302,375 |
|
October 2018 [Member]
|
|
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
| Senior Notes |
276,875 |
262,500 |
|
May 2019 [Member]
|
|
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
| Senior Notes |
262,500 |
251,250 |
|
November 2021 [Member]
|
|
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
| Senior Notes |
167,550 |
158,063 |
|
April 2027 [Member]
|
|
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
| Senior Notes |
$ 195,750 |
$ 194,920 |