Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0001104659-18-029622-index-headers.html | 2018-05-02 10:48:15 | |
| 0001104659-18-029622-index.html | 2018-05-02 10:48:15 | |
| 0001104659-18-029622.txt | 2018-05-02 10:48:15 | |
 0001104659-18-029622-xbrl.zip | 572673 | 2018-05-02 10:48:15 |
| a18-8536_110q.htm | 6612647 | 2018-05-02 10:48:15 |
| a18-8536_1ex12.htm | 96613 | 2018-05-02 10:48:15 |
| a18-8536_1ex31d1.htm | 12499 | 2018-05-02 10:48:15 |
| a18-8536_1ex31d2.htm | 12502 | 2018-05-02 10:48:15 |
| a18-8536_1ex32d1.htm | 4114 | 2018-05-02 10:48:15 |
| a18-8536_1ex32d2.htm | 4188 | 2018-05-02 10:48:15 |
| FilingSummary.xml | 61614 | 2018-05-02 10:48:15 |
| Financial_Report.xlsx | 180778 | 2018-05-02 10:48:15 |
 g85361gmi001.gif | 26397 | 2018-05-02 10:48:15 |
| pfg-20180331.xml | 13582876 | 2018-05-02 10:48:15 |
| pfg-20180331.xsd | 146257 | 2018-05-02 10:48:15 |
| pfg-20180331_cal.xml | 175466 | 2018-05-02 10:48:15 |
| pfg-20180331_def.xml | 625885 | 2018-05-02 10:48:15 |
| pfg-20180331_lab.xml | 1199682 | 2018-05-02 10:48:15 |
| pfg-20180331_pre.xml | 976164 | 2018-05-02 10:48:15 |
| R1.htm | 22226 | 2018-05-02 10:48:15 |
| R10.htm | 1025161 | 2018-05-02 10:48:15 |
| R11.htm | 396788 | 2018-05-02 10:48:15 |
| R12.htm | 44855 | 2018-05-02 10:48:15 |
| R13.htm | 9751 | 2018-05-02 10:48:15 |
| R14.htm | 47248 | 2018-05-02 10:48:15 |
| R15.htm | 39926 | 2018-05-02 10:48:15 |
| R16.htm | 12219 | 2018-05-02 10:48:15 |
| R17.htm | 298422 | 2018-05-02 10:48:15 |
| R18.htm | 1351833 | 2018-05-02 10:48:15 |
| R19.htm | 117020 | 2018-05-02 10:48:15 |
| R2.htm | 102845 | 2018-05-02 10:48:15 |
| R20.htm | 236219 | 2018-05-02 10:48:15 |
| R21.htm | 30227 | 2018-05-02 10:48:15 |
| R22.htm | 45296 | 2018-05-02 10:48:15 |
| R23.htm | 1566675 | 2018-05-02 10:48:15 |
| R24.htm | 8577 | 2018-05-02 10:48:15 |
| R25.htm | 32947 | 2018-05-02 10:48:15 |
| R26.htm | 92208 | 2018-05-02 10:48:15 |
| R27.htm | 1074243 | 2018-05-02 10:48:15 |
| R28.htm | 396455 | 2018-05-02 10:48:15 |
| R29.htm | 46860 | 2018-05-02 10:48:15 |
| R3.htm | 38759 | 2018-05-02 10:48:15 |
| R30.htm | 50544 | 2018-05-02 10:48:15 |
| R31.htm | 40703 | 2018-05-02 10:48:15 |
| R32.htm | 315749 | 2018-05-02 10:48:15 |
| R33.htm | 1329892 | 2018-05-02 10:48:15 |
| R34.htm | 115418 | 2018-05-02 10:48:15 |
| R35.htm | 250161 | 2018-05-02 10:48:15 |
| R36.htm | 28653 | 2018-05-02 10:48:15 |
| R37.htm | 44022 | 2018-05-02 10:48:15 |
| R38.htm | 1566986 | 2018-05-02 10:48:15 |
| R39.htm | 28071 | 2018-05-02 10:48:15 |
| R4.htm | 57263 | 2018-05-02 10:48:15 |
| R40.htm | 28173 | 2018-05-02 10:48:15 |
| R41.htm | 4585 | 2018-05-02 10:48:15 |
| R42.htm | 25038 | 2018-05-02 10:48:15 |
| R43.htm | 34570 | 2018-05-02 10:48:15 |
| R44.htm | 47429 | 2018-05-02 10:48:15 |
| R45.htm | 36883 | 2018-05-02 10:48:15 |
| R46.htm | 40431 | 2018-05-02 10:48:15 |
| R47.htm | 12961 | 2018-05-02 10:48:15 |
| R48.htm | 17139 | 2018-05-02 10:48:15 |
| R49.htm | 83274 | 2018-05-02 10:48:15 |
| R5.htm | 28188 | 2018-05-02 10:48:15 |
| R50.htm | 19752 | 2018-05-02 10:48:15 |
| R51.htm | 70500 | 2018-05-02 10:48:15 |
| R52.htm | 47216 | 2018-05-02 10:48:15 |
| R53.htm | 44330 | 2018-05-02 10:48:15 |
| R54.htm | 37232 | 2018-05-02 10:48:15 |
| R55.htm | 36426 | 2018-05-02 10:48:15 |
| R56.htm | 16342 | 2018-05-02 10:48:15 |
| R57.htm | 9532 | 2018-05-02 10:48:15 |
| R58.htm | 17598 | 2018-05-02 10:48:15 |
| R59.htm | 17787 | 2018-05-02 10:48:15 |
| R6.htm | 49461 | 2018-05-02 10:48:15 |
| R60.htm | 47887 | 2018-05-02 10:48:15 |
| R61.htm | 29250 | 2018-05-02 10:48:15 |
| R62.htm | 39274 | 2018-05-02 10:48:15 |
| R63.htm | 18516 | 2018-05-02 10:48:15 |
| R64.htm | 41658 | 2018-05-02 10:48:15 |
| R65.htm | 15859 | 2018-05-02 10:48:15 |
| R66.htm | 31914 | 2018-05-02 10:48:15 |
| R67.htm | 32156 | 2018-05-02 10:48:15 |
| R68.htm | 25027 | 2018-05-02 10:48:15 |
| R69.htm | 24192 | 2018-05-02 10:48:15 |
| R7.htm | 104240 | 2018-05-02 10:48:15 |
| R70.htm | 28025 | 2018-05-02 10:48:15 |
| R71.htm | 7975 | 2018-05-02 10:48:15 |
| R72.htm | 14943 | 2018-05-02 10:48:15 |
| R73.htm | 63946 | 2018-05-02 10:48:15 |
| R74.htm | 69375 | 2018-05-02 10:48:15 |
| R75.htm | 119310 | 2018-05-02 10:48:15 |
| R76.htm | 130429 | 2018-05-02 10:48:15 |
| R77.htm | 29544 | 2018-05-02 10:48:15 |
| R78.htm | 90601 | 2018-05-02 10:48:15 |
| R79.htm | 11830 | 2018-05-02 10:48:15 |
| R8.htm | 79596 | 2018-05-02 10:48:15 |
| R80.htm | 26921 | 2018-05-02 10:48:15 |
| R81.htm | 41680 | 2018-05-02 10:48:15 |
| R82.htm | 15202 | 2018-05-02 10:48:15 |
| R83.htm | 47767 | 2018-05-02 10:48:15 |
| R84.htm | 24018 | 2018-05-02 10:48:15 |
| R85.htm | 39822 | 2018-05-02 10:48:15 |
| R86.htm | 78909 | 2018-05-02 10:48:15 |
| R87.htm | 10829 | 2018-05-02 10:48:15 |
| R88.htm | 26280 | 2018-05-02 10:48:15 |
| R89.htm | 24688 | 2018-05-02 10:48:15 |
| R9.htm | 104160 | 2018-05-02 10:48:15 |
| R90.htm | 22802 | 2018-05-02 10:48:15 |
| R91.htm | 10441 | 2018-05-02 10:48:15 |
| R92.htm | 33550 | 2018-05-02 10:48:15 |
| R93.htm | 169158 | 2018-05-02 10:48:15 |
| R94.htm | 94435 | 2018-05-02 10:48:15 |
| R95.htm | 103930 | 2018-05-02 10:48:15 |
| R96.htm | 161905 | 2018-05-02 10:48:15 |
| R97.htm | 87522 | 2018-05-02 10:48:15 |
| R98.htm | 100294 | 2018-05-02 10:48:15 |
| report.css | 2768 | 2018-05-02 10:48:15 |
| Show.js | 1411 | 2018-05-02 10:48:15 |