Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0001193125-21-000153-index-headers.html | 2021-01-04 06:05:57 | |
| 0001193125-21-000153-index.html | 2021-01-04 06:05:57 | |
| 0001193125-21-000153.txt | 2021-01-04 06:05:57 | |
 0001193125-21-000153-xbrl.zip | 480425 | 2021-01-04 06:05:57 |
| btu-20201231.xsd | 3081 | 2021-01-04 06:05:57 |
| btu-20201231_lab.xml | 17373 | 2021-01-04 06:05:57 |
| btu-20201231_pre.xml | 10961 | 2021-01-04 06:05:57 |
| d103420d8k.htm | 38649 | 2021-01-04 06:05:57 |
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| Financial_Report.xlsx | 5455 | 2021-01-04 06:05:57 |
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| MetaLinks.json | 18388 | 2021-01-04 06:05:57 |
| R1.htm | 38621 | 2021-01-04 06:05:57 |
| report.css | 2767 | 2021-01-04 06:05:57 |
| Show.js | 1085 | 2021-01-04 06:05:57 |