Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0001166928-21-000018-index-headers.html | 2021-03-01 07:11:23 | |
| 0001166928-21-000018-index.html | 2021-03-01 07:11:23 | |
| 0001166928-21-000018.txt | 2021-03-01 07:11:23 | |
 0001166928-21-000018-xbrl.zip | 687351 | 2021-03-01 07:11:23 |
| FilingSummary.xml | 64984 | 2021-03-01 07:11:23 |
| Financial_Report.xlsx | 170319 | 2021-03-01 07:11:23 |
| MetaLinks.json | 1032218 | 2021-03-01 07:11:23 |
| R1.htm | 63415 | 2021-03-01 07:11:23 |
| R10.htm | 53167 | 2021-03-01 07:11:23 |
| R100.htm | 62532 | 2021-03-01 07:11:23 |
| R101.htm | 49498 | 2021-03-01 07:11:23 |
| R102.htm | 75217 | 2021-03-01 07:11:23 |
| R103.htm | 52711 | 2021-03-01 07:11:23 |
| R11.htm | 22656 | 2021-03-01 07:11:23 |
| R12.htm | 116252 | 2021-03-01 07:11:23 |
| R13.htm | 485370 | 2021-03-01 07:11:23 |
| R14.htm | 16690 | 2021-03-01 07:11:23 |
| R15.htm | 13004 | 2021-03-01 07:11:23 |
| R16.htm | 10976 | 2021-03-01 07:11:23 |
| R17.htm | 38524 | 2021-03-01 07:11:23 |
| R18.htm | 10856 | 2021-03-01 07:11:23 |
| R19.htm | 50046 | 2021-03-01 07:11:23 |
| R2.htm | 93593 | 2021-03-01 07:11:23 |
| R20.htm | 85538 | 2021-03-01 07:11:23 |
| R21.htm | 32888 | 2021-03-01 07:11:23 |
| R22.htm | 6810 | 2021-03-01 07:11:23 |
| R23.htm | 35516 | 2021-03-01 07:11:23 |
| R24.htm | 122394 | 2021-03-01 07:11:23 |
| R25.htm | 18271 | 2021-03-01 07:11:23 |
| R26.htm | 167024 | 2021-03-01 07:11:23 |
| R27.htm | 92864 | 2021-03-01 07:11:23 |
| R28.htm | 74528 | 2021-03-01 07:11:23 |
| R29.htm | 114211 | 2021-03-01 07:11:23 |
| R3.htm | 20484 | 2021-03-01 07:11:23 |
| R30.htm | 22209 | 2021-03-01 07:11:23 |
| R31.htm | 119870 | 2021-03-01 07:11:23 |
| R32.htm | 486803 | 2021-03-01 07:11:23 |
| R33.htm | 16080 | 2021-03-01 07:11:23 |
| R34.htm | 10775 | 2021-03-01 07:11:23 |
| R35.htm | 8462 | 2021-03-01 07:11:23 |
| R36.htm | 34131 | 2021-03-01 07:11:23 |
| R37.htm | 9431 | 2021-03-01 07:11:23 |
| R38.htm | 47012 | 2021-03-01 07:11:23 |
| R39.htm | 87341 | 2021-03-01 07:11:23 |
| R4.htm | 108673 | 2021-03-01 07:11:23 |
| R40.htm | 29263 | 2021-03-01 07:11:23 |
| R41.htm | 35234 | 2021-03-01 07:11:23 |
| R42.htm | 117390 | 2021-03-01 07:11:23 |
| R43.htm | 10130 | 2021-03-01 07:11:23 |
| R44.htm | 157142 | 2021-03-01 07:11:23 |
| R45.htm | 95290 | 2021-03-01 07:11:23 |
| R46.htm | 74555 | 2021-03-01 07:11:23 |
| R47.htm | 9323 | 2021-03-01 07:11:23 |
| R48.htm | 9113 | 2021-03-01 07:11:23 |
| R49.htm | 8900 | 2021-03-01 07:11:23 |
| R5.htm | 50644 | 2021-03-01 07:11:23 |
| R50.htm | 4293 | 2021-03-01 07:11:23 |
| R51.htm | 4260 | 2021-03-01 07:11:23 |
| R52.htm | 4432 | 2021-03-01 07:11:23 |
| R53.htm | 35602 | 2021-03-01 07:11:23 |
| R54.htm | 30220 | 2021-03-01 07:11:23 |
| R55.htm | 26488 | 2021-03-01 07:11:23 |
| R56.htm | 8507 | 2021-03-01 07:11:23 |
| R57.htm | 46372 | 2021-03-01 07:11:23 |
| R58.htm | 4840 | 2021-03-01 07:11:23 |
| R59.htm | 32208 | 2021-03-01 07:11:23 |
| R6.htm | 44181 | 2021-03-01 07:11:23 |
| R60.htm | 12157 | 2021-03-01 07:11:23 |
| R61.htm | 78520 | 2021-03-01 07:11:23 |
| R62.htm | 9593 | 2021-03-01 07:11:23 |
| R63.htm | 59690 | 2021-03-01 07:11:23 |
| R64.htm | 12175 | 2021-03-01 07:11:23 |
| R65.htm | 13179 | 2021-03-01 07:11:23 |
| R66.htm | 5032 | 2021-03-01 07:11:23 |
| R67.htm | 51970 | 2021-03-01 07:11:23 |
| R68.htm | 54232 | 2021-03-01 07:11:23 |
| R69.htm | 28288 | 2021-03-01 07:11:23 |
| R7.htm | 4621 | 2021-03-01 07:11:23 |
| R70.htm | 26595 | 2021-03-01 07:11:23 |
| R71.htm | 20901 | 2021-03-01 07:11:23 |
| R72.htm | 15073 | 2021-03-01 07:11:23 |
| R73.htm | 22820 | 2021-03-01 07:11:23 |
| R74.htm | 22513 | 2021-03-01 07:11:23 |
| R75.htm | 29793 | 2021-03-01 07:11:23 |
| R76.htm | 34045 | 2021-03-01 07:11:23 |
| R77.htm | 25484 | 2021-03-01 07:11:23 |
| R78.htm | 28827 | 2021-03-01 07:11:23 |
| R79.htm | 20461 | 2021-03-01 07:11:23 |
| R8.htm | 103736 | 2021-03-01 07:11:23 |
| R80.htm | 51931 | 2021-03-01 07:11:23 |
| R81.htm | 13253 | 2021-03-01 07:11:23 |
| R82.htm | 19582 | 2021-03-01 07:11:23 |
| R83.htm | 57969 | 2021-03-01 07:11:23 |
| R84.htm | 41277 | 2021-03-01 07:11:23 |
| R85.htm | 6516 | 2021-03-01 07:11:23 |
| R86.htm | 4706 | 2021-03-01 07:11:23 |
| R87.htm | 27711 | 2021-03-01 07:11:23 |
| R88.htm | 29306 | 2021-03-01 07:11:23 |
| R89.htm | 12272 | 2021-03-01 07:11:23 |
| R9.htm | 6788 | 2021-03-01 07:11:23 |
| R90.htm | 37856 | 2021-03-01 07:11:23 |
| R91.htm | 89442 | 2021-03-01 07:11:23 |
| R92.htm | 7679 | 2021-03-01 07:11:23 |
| R93.htm | 10864 | 2021-03-01 07:11:23 |
| R94.htm | 8108 | 2021-03-01 07:11:23 |
| R95.htm | 8103 | 2021-03-01 07:11:23 |
| R96.htm | 62397 | 2021-03-01 07:11:23 |
| R97.htm | 7019 | 2021-03-01 07:11:23 |
| R98.htm | 74519 | 2021-03-01 07:11:23 |
| R99.htm | 6099 | 2021-03-01 07:11:23 |
| report.css | 2768 | 2021-03-01 07:11:23 |
| Show.js | 1086 | 2021-03-01 07:11:23 |
| wtba-20201231.htm | 4696089 | 2021-03-01 07:11:23 |
| wtba-20201231.xsd | 83375 | 2021-03-01 07:11:23 |
| wtba-20201231x10kex1019.htm | 55459 | 2021-03-01 07:11:23 |
| wtba-20201231x10kex1020.htm | 55839 | 2021-03-01 07:11:23 |
| wtba-20201231x10kex21.htm | 6534 | 2021-03-01 07:11:23 |
| wtba-20201231x10kex23.htm | 3636 | 2021-03-01 07:11:23 |
| wtba-20201231x10kex311.htm | 10589 | 2021-03-01 07:11:23 |
| wtba-20201231x10kex312.htm | 10926 | 2021-03-01 07:11:23 |
| wtba-20201231x10kex321.htm | 4147 | 2021-03-01 07:11:23 |
| wtba-20201231x10kex322.htm | 4220 | 2021-03-01 07:11:23 |
| wtba-20201231_cal.xml | 191721 | 2021-03-01 07:11:23 |
| wtba-20201231_def.xml | 489051 | 2021-03-01 07:11:23 |
 wtba-20201231_g1.jpg | 130064 | 2021-03-01 07:11:23 |
| wtba-20201231_htm.xml | 4499645 | 2021-03-01 07:11:23 |
| wtba-20201231_lab.xml | 1063632 | 2021-03-01 07:11:23 |
| wtba-20201231_pre.xml | 738971 | 2021-03-01 07:11:23 |