|
Credit Risk and Fair Value of Financial Instruments Level 4 (Details) (USD $)
In Thousands, unless otherwise specified
|
Sep. 30, 2013
|
Jun. 30, 2013
|
Dec. 31, 2012
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
| Bank credit facility due March 2016 |
$ 0 |
$ 86,600 |
$ 86,600 |
| Mortgage notes and other debt, maturities through 2047 |
4,711 |
|
5,698 |
| Total fair value of debt instruments |
2,221,612 |
|
1,991,339 |
|
February 2013 [Member]
|
|
|
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
| Senior Notes |
0 |
|
4,786 |
|
April 2015 [Member]
|
|
|
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
| Senior Notes |
145,676 |
|
150,112 |
|
April 2016 [Member]
|
|
|
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
| Senior Notes |
216,621 |
|
222,049 |
|
June 2017 [Member]
|
|
|
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
| Senior Notes |
327,450 |
|
341,094 |
|
October 2018 [Member]
|
|
|
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
| Senior Notes |
284,560 |
|
298,750 |
|
May 2019 [Member]
|
|
|
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
| Senior Notes |
266,875 |
|
276,250 |
|
November 2020 [Member]
|
|
|
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
| Senior Notes |
190,500 |
|
204,500 |
|
November 2021 [Member]
|
|
|
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
| Senior Notes |
170,250 |
|
186,000 |
|
January 2022 [Member]
|
|
|
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
| Senior Notes |
407,469 |
|
0 |
|
April 2027 [Member]
|
|
|
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
| Senior Notes |
$ 207,500 |
|
$ 215,500 |