Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0000931148-16-000108-index-headers.html | 2016-03-08 09:04:21 | |
| 0000931148-16-000108-index.html | 2016-03-08 09:04:21 | |
| 0000931148-16-000108.txt | 2016-03-08 09:04:21 | |
 0000931148-16-000108-xbrl.zip | 602548 | 2016-03-08 09:04:21 |
| a1210ratioofearningstofixe.htm | 49706 | 2016-03-08 09:04:21 |
| a201510-k.htm | 5012182 | 2016-03-08 09:04:21 |
| a201510kex311.htm | 10451 | 2016-03-08 09:04:21 |
| a201510kex312.htm | 10445 | 2016-03-08 09:04:21 |
| a201510kex321.htm | 7439 | 2016-03-08 09:04:21 |
| a201510kex322.htm | 7269 | 2016-03-08 09:04:21 |
 filinglogoa19.jpg | 22476 | 2016-03-08 09:04:21 |
| FilingSummary.xml | 78377 | 2016-03-08 09:04:21 |
| Financial_Report.xlsx | 197794 | 2016-03-08 09:04:21 |
| gti-20151231.xml | 8458349 | 2016-03-08 09:04:21 |
| gti-20151231.xsd | 95915 | 2016-03-08 09:04:21 |
| gti-20151231_cal.xml | 165595 | 2016-03-08 09:04:21 |
| gti-20151231_def.xml | 884986 | 2016-03-08 09:04:21 |
| gti-20151231_lab.xml | 1244684 | 2016-03-08 09:04:21 |
| gti-20151231_pre.xml | 1043770 | 2016-03-08 09:04:21 |
| R1.htm | 28407 | 2016-03-08 09:04:21 |
| R10.htm | 56791 | 2016-03-08 09:04:21 |
| R100.htm | 28128 | 2016-03-08 09:04:21 |
| R101.htm | 41352 | 2016-03-08 09:04:21 |
| R102.htm | 57970 | 2016-03-08 09:04:21 |
| R103.htm | 17254 | 2016-03-08 09:04:21 |
| R104.htm | 24140 | 2016-03-08 09:04:21 |
| R105.htm | 10425 | 2016-03-08 09:04:21 |
| R106.htm | 5500 | 2016-03-08 09:04:21 |
| R107.htm | 21449 | 2016-03-08 09:04:21 |
| R108.htm | 9683 | 2016-03-08 09:04:21 |
| R109.htm | 234130 | 2016-03-08 09:04:21 |
| R11.htm | 474573 | 2016-03-08 09:04:21 |
| R110.htm | 171850 | 2016-03-08 09:04:21 |
| R111.htm | 170289 | 2016-03-08 09:04:21 |
| R112.htm | 15193 | 2016-03-08 09:04:21 |
| R113.htm | 6327 | 2016-03-08 09:04:21 |
| R114.htm | 8967 | 2016-03-08 09:04:21 |
| R12.htm | 119704 | 2016-03-08 09:04:21 |
| R13.htm | 72842 | 2016-03-08 09:04:21 |
| R14.htm | 35703 | 2016-03-08 09:04:21 |
| R15.htm | 32933 | 2016-03-08 09:04:21 |
| R16.htm | 111013 | 2016-03-08 09:04:21 |
| R17.htm | 71740 | 2016-03-08 09:04:21 |
| R18.htm | 12475 | 2016-03-08 09:04:21 |
| R19.htm | 588383 | 2016-03-08 09:04:21 |
| R2.htm | 107832 | 2016-03-08 09:04:21 |
| R20.htm | 32456 | 2016-03-08 09:04:21 |
| R21.htm | 14957 | 2016-03-08 09:04:21 |
| R22.htm | 200349 | 2016-03-08 09:04:21 |
| R23.htm | 21263 | 2016-03-08 09:04:21 |
| R24.htm | 20924 | 2016-03-08 09:04:21 |
| R25.htm | 1226169 | 2016-03-08 09:04:21 |
| R26.htm | 6996 | 2016-03-08 09:04:21 |
| R27.htm | 6668 | 2016-03-08 09:04:21 |
| R28.htm | 6669 | 2016-03-08 09:04:21 |
| R29.htm | 126873 | 2016-03-08 09:04:21 |
| R3.htm | 26907 | 2016-03-08 09:04:21 |
| R30.htm | 14559 | 2016-03-08 09:04:21 |
| R31.htm | 52098 | 2016-03-08 09:04:21 |
| R32.htm | 466240 | 2016-03-08 09:04:21 |
| R33.htm | 113272 | 2016-03-08 09:04:21 |
| R34.htm | 63321 | 2016-03-08 09:04:21 |
| R35.htm | 38879 | 2016-03-08 09:04:21 |
| R36.htm | 30142 | 2016-03-08 09:04:21 |
| R37.htm | 96443 | 2016-03-08 09:04:21 |
| R38.htm | 73527 | 2016-03-08 09:04:21 |
| R39.htm | 12584 | 2016-03-08 09:04:21 |
| R4.htm | 80616 | 2016-03-08 09:04:21 |
| R40.htm | 549960 | 2016-03-08 09:04:21 |
| R41.htm | 29011 | 2016-03-08 09:04:21 |
| R42.htm | 10192 | 2016-03-08 09:04:21 |
| R43.htm | 178133 | 2016-03-08 09:04:21 |
| R44.htm | 18706 | 2016-03-08 09:04:21 |
| R45.htm | 18045 | 2016-03-08 09:04:21 |
| R46.htm | 1223253 | 2016-03-08 09:04:21 |
| R47.htm | 45376 | 2016-03-08 09:04:21 |
| R48.htm | 16351 | 2016-03-08 09:04:21 |
| R49.htm | 14348 | 2016-03-08 09:04:21 |
| R5.htm | 5132 | 2016-03-08 09:04:21 |
| R50.htm | 37622 | 2016-03-08 09:04:21 |
| R51.htm | 16756 | 2016-03-08 09:04:21 |
| R52.htm | 41283 | 2016-03-08 09:04:21 |
| R53.htm | 10155 | 2016-03-08 09:04:21 |
| R54.htm | 159739 | 2016-03-08 09:04:21 |
| R55.htm | 152637 | 2016-03-08 09:04:21 |
| R56.htm | 48343 | 2016-03-08 09:04:21 |
| R57.htm | 20921 | 2016-03-08 09:04:21 |
| R58.htm | 61277 | 2016-03-08 09:04:21 |
| R59.htm | 10536 | 2016-03-08 09:04:21 |
| R6.htm | 142929 | 2016-03-08 09:04:21 |
| R60.htm | 13539 | 2016-03-08 09:04:21 |
| R61.htm | 25933 | 2016-03-08 09:04:21 |
| R62.htm | 28989 | 2016-03-08 09:04:21 |
| R63.htm | 16923 | 2016-03-08 09:04:21 |
| R64.htm | 27697 | 2016-03-08 09:04:21 |
| R65.htm | 65905 | 2016-03-08 09:04:21 |
| R66.htm | 20917 | 2016-03-08 09:04:21 |
| R67.htm | 16035 | 2016-03-08 09:04:21 |
| R68.htm | 4860 | 2016-03-08 09:04:21 |
| R69.htm | 36026 | 2016-03-08 09:04:21 |
| R7.htm | 83102 | 2016-03-08 09:04:21 |
| R70.htm | 34812 | 2016-03-08 09:04:21 |
| R71.htm | 17780 | 2016-03-08 09:04:21 |
| R72.htm | 15352 | 2016-03-08 09:04:21 |
| R73.htm | 17517 | 2016-03-08 09:04:21 |
| R74.htm | 54802 | 2016-03-08 09:04:21 |
| R75.htm | 10056 | 2016-03-08 09:04:21 |
| R76.htm | 5184 | 2016-03-08 09:04:21 |
| R77.htm | 17164 | 2016-03-08 09:04:21 |
| R78.htm | 46280 | 2016-03-08 09:04:21 |
| R79.htm | 57571 | 2016-03-08 09:04:21 |
| R8.htm | 5312 | 2016-03-08 09:04:21 |
| R80.htm | 23862 | 2016-03-08 09:04:21 |
| R81.htm | 149784 | 2016-03-08 09:04:21 |
| R82.htm | 48038 | 2016-03-08 09:04:21 |
| R83.htm | 16594 | 2016-03-08 09:04:21 |
| R84.htm | 17511 | 2016-03-08 09:04:21 |
| R85.htm | 18301 | 2016-03-08 09:04:21 |
| R86.htm | 18461 | 2016-03-08 09:04:21 |
| R87.htm | 25562 | 2016-03-08 09:04:21 |
| R88.htm | 24730 | 2016-03-08 09:04:21 |
| R89.htm | 20752 | 2016-03-08 09:04:21 |
| R9.htm | 63617 | 2016-03-08 09:04:21 |
| R90.htm | 81497 | 2016-03-08 09:04:21 |
| R91.htm | 17519 | 2016-03-08 09:04:21 |
| R92.htm | 17438 | 2016-03-08 09:04:21 |
| R93.htm | 25573 | 2016-03-08 09:04:21 |
| R94.htm | 32692 | 2016-03-08 09:04:21 |
| R95.htm | 23485 | 2016-03-08 09:04:21 |
| R96.htm | 22457 | 2016-03-08 09:04:21 |
| R97.htm | 9408 | 2016-03-08 09:04:21 |
| R98.htm | 56880 | 2016-03-08 09:04:21 |
| R99.htm | 14908 | 2016-03-08 09:04:21 |
| report.css | 2768 | 2016-03-08 09:04:21 |
| Show.js | 1411 | 2016-03-08 09:04:21 |