| Date Filed | Type | Description |
| 03/29/2022 |
10-K
| Annual Report for the period ended December 31, 2021 |
| 04/16/2021 |
10-K/A
| Annual Report for the period ended December 31, 2020 [amend] |
| 03/31/2021 |
10-K
| Annual Report for the period ended December 31, 2020 |
| 03/30/2020 |
10-K
| Annual Report for the period ended December 31, 2019 |
| 04/01/2019 |
10-K
| Annual Report for the period ended December 31, 2018 |
| 04/02/2018 |
10-K
| Annual Report for the period ended December 31, 2017 |
| 03/16/2017 |
10-K
| Annual Report for the period ended December 31, 2016 |
| 03/14/2016 |
10-KT
| Form 10-KT - Transition reports [Rule 13a-10 or 15d-10] |
| 07/14/2015 |
10-K
| Annual Report for the period ended April 30, 2015 |
| 07/29/2014 |
10-K
| Annual Report for the period ended April 30, 2014 |
| 06/26/2013 |
10-K
| Annual Report for the period ended April 30, 2013 |
| 07/24/2012 |
10-K
| Annual Report for the period ended April 30, 2012 |
| 08/29/2011 |
10-K/A
| Annual Report for the period ended April 30, 2011 [amend] |
| 07/14/2011 |
10-K
| Annual Report for the period ended April 30, 2011 |
| 07/23/2010 |
10-K
| Annual Report for the period ended April 30, 2010 |
| 03/25/2010 |
10-K/A
| Annual Report for the period ended April 30, 2009 [amend] |
| 08/12/2009 |
10-K
| Annual Report for the period ended April 30, 2009 |
| 08/13/2008 |
10-K
| Annual Report for the period ended April 30, 2008 |
| 08/14/2007 |
10-K
| Annual Report for the period ended April 30, 2007 |
| 07/28/2006 |
10-K
| Annual Report for the period ended April 30, 2006 |
| 08/15/2005 |
10-K
| Annual Report for the period ended April 30, 2005 |
| 08/13/2004 |
10-K
| Annual Report for the period ended April 30, 2004 |
| 07/18/2003 |
10-K
| Annual Report for the period ended April 30, 2003 |
| 07/26/2002 |
10-K
| Annual Report for the period ended April 30, 2002 |
| 07/26/2001 |
10-K
| Annual Report for the period ended April 30, 2001 |
| 08/03/2000 |
10-K405
| Form 10-K405 - Annual report [Sections 13 and 15(d), S-K Item 405] |
| 09/01/1999 |
10-K405
| Form 10-K405 - Annual report [Sections 13 and 15(d), S-K Item 405] |
| 07/29/1998 |
10-K405
| Form 10-K405 - Annual report [Sections 13 and 15(d), S-K Item 405] |
| 07/29/1997 |
10-K405
| Form 10-K405 - Annual report [Sections 13 and 15(d), S-K Item 405] |
| 08/02/1996 |
10-K405
| Form 10-K405 - Annual report [Sections 13 and 15(d), S-K Item 405] |