| Date | Acquired | Amount |
|---|---|---|
| Oct 23, 2017 |
|
Undisclosed amount |
| Apr 28, 2017 |
|
Undisclosed amount |
| Mar 21, 2017 |
|
Undisclosed amount |
| Jan 06, 2017 |
|
Undisclosed amount |
| Aug 09, 2016 |
|
Undisclosed amount |
| Jun 07, 2016 |
|
Undisclosed amount |
| Dec 21, 2015 |
|
$ 1,500,000,000 |
| Mar 16, 2015 |
|
Undisclosed amount |
| Apr 08, 2013 |
|
Undisclosed amount |
| Dec 10, 2009 |
|
Undisclosed amount |
| Apr 04, 2006 |
|
Undisclosed amount |
