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|---|---|---|
 0001193125-19-086276-index-headers.html | 2019-03-26 12:12:35 | |
| 0001193125-19-086276-index.html | 2019-03-26 12:12:35 | |
| 0001193125-19-086276.txt | 2019-03-26 12:12:35 | |
 0001193125-19-086276-xbrl.zip | 94192 | 2019-03-26 12:12:35 |
| d684135d10k.htm | 816086 | 2019-03-26 12:12:35 |
| d684135dex105d.htm | 7007 | 2019-03-26 12:12:35 |
| d684135dex311.htm | 11571 | 2019-03-26 12:12:35 |
| d684135dex312.htm | 11573 | 2019-03-26 12:12:35 |
| d684135dex321.htm | 4600 | 2019-03-26 12:12:35 |
| d684135dex322.htm | 4433 | 2019-03-26 12:12:35 |
| FilingSummary.xml | 20541 | 2019-03-26 12:12:35 |
| Financial_Report.xlsx | 42212 | 2019-03-26 12:12:35 |
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| poto-20181231.xml | 848096 | 2019-03-26 12:12:35 |
| poto-20181231.xsd | 29830 | 2019-03-26 12:12:35 |
| poto-20181231_cal.xml | 40215 | 2019-03-26 12:12:35 |
| poto-20181231_def.xml | 156924 | 2019-03-26 12:12:35 |
| poto-20181231_lab.xml | 236031 | 2019-03-26 12:12:35 |
| poto-20181231_pre.xml | 193109 | 2019-03-26 12:12:35 |
| R1.htm | 39604 | 2019-03-26 12:12:35 |
| R10.htm | 136728 | 2019-03-26 12:12:35 |
| R11.htm | 43597 | 2019-03-26 12:12:35 |
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| R2.htm | 57222 | 2019-03-26 12:12:35 |
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| R8.htm | 15887 | 2019-03-26 12:12:35 |
| R9.htm | 16206 | 2019-03-26 12:12:35 |
| report.css | 2767 | 2019-03-26 12:12:35 |
| Show.js | 1085 | 2019-03-26 12:12:35 |