| Date | Acquired | Amount |
|---|---|---|
| Aug 27, 2015 |
|
$ 1,700,000,000 |
| Aug 12, 2014 |
|
Undisclosed amount |
| Feb 17, 2012 |
|
$ 12,000,000 |
| Nov 26, 2007 |
|
$ 125,000,000 |
| Oct 30, 2007 |
|
$ 55,000,000 |
| Apr 30, 2007 |
|
$ 102,000,000 |
| Apr 09, 2007 |
|
$ 11,400,000 |
| Mar 16, 2004 |
|
$ 45,000,000 |
| Jul 09, 2002 |
|
$ 57,000,000 |
