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|---|---|---|
 0000784977-21-000011-index-headers.html | 2021-02-19 08:54:00 | |
| 0000784977-21-000011-index.html | 2021-02-19 08:54:00 | |
| 0000784977-21-000011.txt | 2021-02-19 08:54:00 | |
 0000784977-21-000011-xbrl.zip | 37052 | 2021-02-19 08:54:00 |
| a2020q4ex991-pressrelease.htm | 363749 | 2021-02-19 08:54:00 |
| FilingSummary.xml | 1837 | 2021-02-19 08:54:00 |
| Financial_Report.xlsx | 5524 | 2021-02-19 08:54:00 |
 logoa051.jpg | 12600 | 2021-02-19 08:54:00 |
| MetaLinks.json | 20730 | 2021-02-19 08:54:00 |
| por-20210219.htm | 38406 | 2021-02-19 08:54:00 |
| por-20210219.xsd | 2580 | 2021-02-19 08:54:00 |
| por-20210219_cal.xml | 723 | 2021-02-19 08:54:00 |
| por-20210219_def.xml | 6372 | 2021-02-19 08:54:00 |
| por-20210219_htm.xml | 13203 | 2021-02-19 08:54:00 |
| por-20210219_lab.xml | 29958 | 2021-02-19 08:54:00 |
| por-20210219_pre.xml | 16025 | 2021-02-19 08:54:00 |
| q42020earningsslides-fin.htm | 15287 | 2021-02-19 08:54:00 |
 q42020earningsslides-fin001.jpg | 117254 | 2021-02-19 08:54:00 |
 q42020earningsslides-fin002.jpg | 202935 | 2021-02-19 08:54:00 |
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 q42020earningsslides-fin005.jpg | 91953 | 2021-02-19 08:54:00 |
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 q42020earningsslides-fin007.jpg | 103177 | 2021-02-19 08:54:00 |
 q42020earningsslides-fin008.jpg | 64223 | 2021-02-19 08:54:00 |
 q42020earningsslides-fin009.jpg | 69942 | 2021-02-19 08:54:00 |
 q42020earningsslides-fin010.jpg | 139526 | 2021-02-19 08:54:00 |
 q42020earningsslides-fin011.jpg | 129213 | 2021-02-19 08:54:00 |
 q42020earningsslides-fin012.jpg | 104779 | 2021-02-19 08:54:00 |
| R1.htm | 41955 | 2021-02-19 08:54:00 |
| report.css | 2767 | 2021-02-19 08:54:00 |
| Show.js | 1085 | 2021-02-19 08:54:00 |