Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0001628280-24-022952-index-headers.html | 2024-05-13 17:12:16 | |
| 0001628280-24-022952-index.html | 2024-05-13 17:12:16 | |
| 0001628280-24-022952.txt | 2024-05-13 17:12:16 | |
 0001628280-24-022952-xbrl.zip | 240800 | 2024-05-13 17:12:16 |
| exhibit311q124.htm | 12605 | 2024-05-13 17:12:16 |
| exhibit312q124.htm | 12511 | 2024-05-13 17:12:16 |
| exhibit321q124.htm | 7034 | 2024-05-13 17:12:16 |
| exhibit322q124.htm | 7084 | 2024-05-13 17:12:16 |
| FilingSummary.xml | 30765 | 2024-05-13 17:12:16 |
| Financial_Report.xlsx | 84997 | 2024-05-13 17:12:16 |
| MetaLinks.json | 744143 | 2024-05-13 17:12:16 |
| opc-20240331.htm | 1096127 | 2024-05-13 17:12:16 |
| opc-20240331.xsd | 64592 | 2024-05-13 17:12:16 |
| opc-20240331_cal.xml | 108821 | 2024-05-13 17:12:16 |
| opc-20240331_def.xml | 192918 | 2024-05-13 17:12:16 |
 opc-20240331_g1.jpg | 14876 | 2024-05-13 17:12:16 |
| opc-20240331_htm.xml | 1274494 | 2024-05-13 17:12:16 |
| opc-20240331_lab.xml | 666700 | 2024-05-13 17:12:16 |
| opc-20240331_pre.xml | 417608 | 2024-05-13 17:12:16 |
| 397880 | 2024-05-13 17:12:16 | |
| R1.htm | 45439 | 2024-05-13 17:12:16 |
| R10.htm | 16345 | 2024-05-13 17:12:16 |
| R11.htm | 40166 | 2024-05-13 17:12:16 |
| R12.htm | 262354 | 2024-05-13 17:12:16 |
| R13.htm | 12874 | 2024-05-13 17:12:16 |
| R14.htm | 12781 | 2024-05-13 17:12:16 |
| R15.htm | 47545 | 2024-05-13 17:12:16 |
| R16.htm | 5028 | 2024-05-13 17:12:16 |
| R17.htm | 13637 | 2024-05-13 17:12:16 |
| R18.htm | 8288 | 2024-05-13 17:12:16 |
| R19.htm | 5238 | 2024-05-13 17:12:16 |
| R2.htm | 123740 | 2024-05-13 17:12:16 |
| R20.htm | 5898 | 2024-05-13 17:12:16 |
| R21.htm | 5274 | 2024-05-13 17:12:16 |
| R22.htm | 8485 | 2024-05-13 17:12:16 |
| R23.htm | 6870 | 2024-05-13 17:12:16 |
| R24.htm | 116543 | 2024-05-13 17:12:16 |
| R25.htm | 45418 | 2024-05-13 17:12:16 |
| R26.htm | 32644 | 2024-05-13 17:12:16 |
| R27.htm | 23440 | 2024-05-13 17:12:16 |
| R28.htm | 113104 | 2024-05-13 17:12:16 |
| R29.htm | 13034 | 2024-05-13 17:12:16 |
| R3.htm | 52464 | 2024-05-13 17:12:16 |
| R30.htm | 46708 | 2024-05-13 17:12:16 |
| R31.htm | 4153 | 2024-05-13 17:12:16 |
| R32.htm | 111323 | 2024-05-13 17:12:16 |
| R33.htm | 9168 | 2024-05-13 17:12:16 |
| R34.htm | 24655 | 2024-05-13 17:12:16 |
| R35.htm | 27573 | 2024-05-13 17:12:16 |
| R36.htm | 16021 | 2024-05-13 17:12:16 |
| R37.htm | 38617 | 2024-05-13 17:12:16 |
| R38.htm | 12340 | 2024-05-13 17:12:16 |
| R39.htm | 39920 | 2024-05-13 17:12:16 |
| R4.htm | 12123 | 2024-05-13 17:12:16 |
| R40.htm | 19801 | 2024-05-13 17:12:16 |
| R41.htm | 20912 | 2024-05-13 17:12:16 |
| R42.htm | 38667 | 2024-05-13 17:12:16 |
| R43.htm | 24119 | 2024-05-13 17:12:16 |
| R44.htm | 68015 | 2024-05-13 17:12:16 |
| R45.htm | 7844 | 2024-05-13 17:12:16 |
| R46.htm | 12339 | 2024-05-13 17:12:16 |
| R47.htm | 68119 | 2024-05-13 17:12:16 |
| R48.htm | 30201 | 2024-05-13 17:12:16 |
| R49.htm | 16541 | 2024-05-13 17:12:16 |
| R5.htm | 102368 | 2024-05-13 17:12:16 |
| R50.htm | 27269 | 2024-05-13 17:12:16 |
| R51.htm | 8619 | 2024-05-13 17:12:16 |
| R52.htm | 7932 | 2024-05-13 17:12:16 |
| R6.htm | 7607 | 2024-05-13 17:12:16 |
| R7.htm | 125098 | 2024-05-13 17:12:16 |
| R8.htm | 45406 | 2024-05-13 17:12:16 |
| R9.htm | 36424 | 2024-05-13 17:12:16 |
| report.css | 2767 | 2024-05-13 17:12:16 |
| Show.js | 1085 | 2024-05-13 17:12:16 |