Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0001193125-14-055202-index-headers.html | 2014-02-14 17:17:18 | |
| 0001193125-14-055202-index.html | 2014-02-14 17:17:18 | |
| 0001193125-14-055202.txt | 2014-02-14 17:17:18 | |
 0001193125-14-055202-xbrl.zip | 364498 | 2014-02-14 17:17:18 |
| d639801d10k.htm | 2590947 | 2014-02-14 17:17:18 |
| d639801dex1018.htm | 72807 | 2014-02-14 17:17:18 |
| d639801dex1019.htm | 70246 | 2014-02-14 17:17:18 |
| d639801dex111.htm | 10228 | 2014-02-14 17:17:18 |
| d639801dex211.htm | 5383 | 2014-02-14 17:17:18 |
| d639801dex231.htm | 2039 | 2014-02-14 17:17:18 |
| d639801dex311.htm | 9575 | 2014-02-14 17:17:18 |
| d639801dex312.htm | 9575 | 2014-02-14 17:17:18 |
| d639801dex321.htm | 3542 | 2014-02-14 17:17:18 |
| d639801dex322.htm | 3543 | 2014-02-14 17:17:18 |
| FilingSummary.xml | 60949 | 2014-02-14 17:17:18 |
| Financial_Report.xls | 2727890 | 2014-02-14 17:17:18 |
| Financial_Report.xlsx | 454599 | 2014-02-14 17:17:18 |
 g639801g47j74.jpg | 78510 | 2014-02-14 17:17:18 |
| navg-20131231.xml | 3419609 | 2014-02-14 17:17:18 |
| navg-20131231.xsd | 109511 | 2014-02-14 17:17:18 |
| navg-20131231_cal.xml | 160053 | 2014-02-14 17:17:18 |
| navg-20131231_def.xml | 753807 | 2014-02-14 17:17:18 |
| navg-20131231_lab.xml | 879196 | 2014-02-14 17:17:18 |
| navg-20131231_pre.xml | 881134 | 2014-02-14 17:17:18 |
| R1.htm | 39414 | 2014-02-14 17:17:18 |
| R10.htm | 34292 | 2014-02-14 17:17:18 |
| R100.htm | 9534 | 2014-02-14 17:17:18 |
| R101.htm | 50215 | 2014-02-14 17:17:18 |
| R102.htm | 29071 | 2014-02-14 17:17:18 |
| R103.htm | 17449 | 2014-02-14 17:17:18 |
| R104.htm | 39030 | 2014-02-14 17:17:18 |
| R11.htm | 14864 | 2014-02-14 17:17:18 |
| R12.htm | 154399 | 2014-02-14 17:17:18 |
| R13.htm | 308317 | 2014-02-14 17:17:18 |
| R14.htm | 61155 | 2014-02-14 17:17:18 |
| R15.htm | 74625 | 2014-02-14 17:17:18 |
| R16.htm | 50770 | 2014-02-14 17:17:18 |
| R17.htm | 6183 | 2014-02-14 17:17:18 |
| R18.htm | 7468 | 2014-02-14 17:17:18 |
| R19.htm | 5964 | 2014-02-14 17:17:18 |
| R2.htm | 117766 | 2014-02-14 17:17:18 |
| R20.htm | 13536 | 2014-02-14 17:17:18 |
| R21.htm | 24021 | 2014-02-14 17:17:18 |
| R22.htm | 27371 | 2014-02-14 17:17:18 |
| R23.htm | 77575 | 2014-02-14 17:17:18 |
| R24.htm | 7265 | 2014-02-14 17:17:18 |
| R25.htm | 77848 | 2014-02-14 17:17:18 |
| R26.htm | 25819 | 2014-02-14 17:17:18 |
| R27.htm | 74236 | 2014-02-14 17:17:18 |
| R28.htm | 44577 | 2014-02-14 17:17:18 |
| R29.htm | 18213 | 2014-02-14 17:17:18 |
| R3.htm | 27071 | 2014-02-14 17:17:18 |
| R30.htm | 12475 | 2014-02-14 17:17:18 |
| R31.htm | 28347 | 2014-02-14 17:17:18 |
| R32.htm | 79477 | 2014-02-14 17:17:18 |
| R33.htm | 13766 | 2014-02-14 17:17:18 |
| R34.htm | 149856 | 2014-02-14 17:17:18 |
| R35.htm | 327671 | 2014-02-14 17:17:18 |
| R36.htm | 42625 | 2014-02-14 17:17:18 |
| R37.htm | 75264 | 2014-02-14 17:17:18 |
| R38.htm | 50062 | 2014-02-14 17:17:18 |
| R39.htm | 8467 | 2014-02-14 17:17:18 |
| R4.htm | 90659 | 2014-02-14 17:17:18 |
| R40.htm | 26561 | 2014-02-14 17:17:18 |
| R41.htm | 15433 | 2014-02-14 17:17:18 |
| R42.htm | 80989 | 2014-02-14 17:17:18 |
| R43.htm | 76486 | 2014-02-14 17:17:18 |
| R44.htm | 22936 | 2014-02-14 17:17:18 |
| R45.htm | 34243 | 2014-02-14 17:17:18 |
| R46.htm | 26269 | 2014-02-14 17:17:18 |
| R47.htm | 135714 | 2014-02-14 17:17:18 |
| R48.htm | 58324 | 2014-02-14 17:17:18 |
| R49.htm | 44219 | 2014-02-14 17:17:18 |
| R5.htm | 40768 | 2014-02-14 17:17:18 |
| R50.htm | 29076 | 2014-02-14 17:17:18 |
| R51.htm | 45256 | 2014-02-14 17:17:18 |
| R52.htm | 21448 | 2014-02-14 17:17:18 |
| R53.htm | 74286 | 2014-02-14 17:17:18 |
| R54.htm | 29301 | 2014-02-14 17:17:18 |
| R55.htm | 15846 | 2014-02-14 17:17:18 |
| R56.htm | 24430 | 2014-02-14 17:17:18 |
| R57.htm | 21562 | 2014-02-14 17:17:18 |
| R58.htm | 11699 | 2014-02-14 17:17:18 |
| R59.htm | 23283 | 2014-02-14 17:17:18 |
| R6.htm | 17271 | 2014-02-14 17:17:18 |
| R60.htm | 37291 | 2014-02-14 17:17:18 |
| R61.htm | 33425 | 2014-02-14 17:17:18 |
| R62.htm | 33792 | 2014-02-14 17:17:18 |
| R63.htm | 17240 | 2014-02-14 17:17:18 |
| R64.htm | 45025 | 2014-02-14 17:17:18 |
| R65.htm | 28229 | 2014-02-14 17:17:18 |
| R66.htm | 46710 | 2014-02-14 17:17:18 |
| R67.htm | 21548 | 2014-02-14 17:17:18 |
| R68.htm | 11268 | 2014-02-14 17:17:18 |
| R69.htm | 124979 | 2014-02-14 17:17:18 |
| R7.htm | 61086 | 2014-02-14 17:17:18 |
| R70.htm | 12419 | 2014-02-14 17:17:18 |
| R71.htm | 46252 | 2014-02-14 17:17:18 |
| R72.htm | 29549 | 2014-02-14 17:17:18 |
| R73.htm | 33659 | 2014-02-14 17:17:18 |
| R74.htm | 57525 | 2014-02-14 17:17:18 |
| R75.htm | 42924 | 2014-02-14 17:17:18 |
| R76.htm | 18422 | 2014-02-14 17:17:18 |
| R77.htm | 56542 | 2014-02-14 17:17:18 |
| R78.htm | 14020 | 2014-02-14 17:17:18 |
| R79.htm | 24866 | 2014-02-14 17:17:18 |
| R8.htm | 128505 | 2014-02-14 17:17:18 |
| R80.htm | 23737 | 2014-02-14 17:17:18 |
| R81.htm | 17372 | 2014-02-14 17:17:18 |
| R82.htm | 20846 | 2014-02-14 17:17:18 |
| R83.htm | 10637 | 2014-02-14 17:17:18 |
| R84.htm | 18545 | 2014-02-14 17:17:18 |
| R85.htm | 6551 | 2014-02-14 17:17:18 |
| R86.htm | 52035 | 2014-02-14 17:17:18 |
| R87.htm | 97489 | 2014-02-14 17:17:18 |
| R88.htm | 15233 | 2014-02-14 17:17:18 |
| R89.htm | 21372 | 2014-02-14 17:17:18 |
| R9.htm | 6399 | 2014-02-14 17:17:18 |
| R90.htm | 35935 | 2014-02-14 17:17:18 |
| R91.htm | 34717 | 2014-02-14 17:17:18 |
| R92.htm | 37300 | 2014-02-14 17:17:18 |
| R93.htm | 33105 | 2014-02-14 17:17:18 |
| R94.htm | 94389 | 2014-02-14 17:17:18 |
| R95.htm | 44226 | 2014-02-14 17:17:18 |
| R96.htm | 74305 | 2014-02-14 17:17:18 |
| R97.htm | 26403 | 2014-02-14 17:17:18 |
| R98.htm | 59342 | 2014-02-14 17:17:18 |
| R99.htm | 87512 | 2014-02-14 17:17:18 |
| report.css | 2740 | 2014-02-14 17:17:18 |
| Show.js | 1410 | 2014-02-14 17:17:18 |