| Date | Acquired | Amount |
|---|---|---|
| Feb 27, 2017 |
|
Undisclosed amount |
| Mar 02, 2010 |
|
Undisclosed amount |
| Apr 17, 2008 |
|
Undisclosed amount |
| Oct 15, 2004 |
|
$ 519,000,000 |
| Feb 19, 2004 |
|
$ 85,000,000 |
