| Date | Acquired | Amount |
|---|---|---|
| Sep 23, 2014 |
|
$ 107,500,000 |
| Aug 13, 2013 |
|
$ 225,000,000 |
| Feb 21, 2013 |
|
Undisclosed amount |
| May 25, 2011 |
|
Undisclosed amount |
| Feb 23, 2010 |
|
Undisclosed amount |
