| Date | Acquired | Amount |
|---|---|---|
| Oct 14, 2015 |
|
Undisclosed amount |
| Apr 21, 2014 |
|
$ 45,000,000 |
| Aug 01, 2013 |
|
Undisclosed amount |
| Jan 09, 2012 |
|
$ 287,500,000 |
| May 11, 2010 |
|
Undisclosed amount |
| Jan 09, 2002 |
|
Undisclosed amount |
| Jul 26, 2000 |
|
$ 4,000,000,000 |
