Quarterly Financial Data (unaudited) - Quarterly Financial Data (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2019
Sep. 30, 2019
Jun. 30, 2019
Mar. 31, 2019
Dec. 31, 2018
Sep. 30, 2018
Jun. 30, 2018
Mar. 31, 2018
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Revenues:                      
Product revenues, net $ 1,413,265 $ 949,828 $ 941,293 $ 858,435 $ 870,106 $ 784,535 $ 752,157 $ 640,799 $ 4,162,821 $ 3,047,597 $ 2,488,652
Costs and expenses:                      
Cost of sales 185,012 131,914 135,740 95,092 122,289 111,255 104,382 71,613 547,758 409,539 275,119
Research and development expenses 480,011 555,948 379,091 339,490 437,881 330,510 337,532 310,553 1,754,540 1,416,476 1,324,625
Sales, general and administrative expenses 195,277 159,674 156,502 147,045 153,210 137,295 137,303 129,808 658,498 557,616 496,079
Increase in fair value of contingent consideration 1,500 2,959 0 0         4,459 0 0
Restructuring (income) expenses         4 (174) 62 (76) 0 184 (14,246)
Intangible asset impairment charges         29,000 0 0 0 0 29,000 255,340
Total costs and expenses 861,800 850,495 671,333 581,627 742,384 578,886 579,279 511,898 2,965,255 2,412,447 2,365,409
Income from operations 551,465 99,333 269,960 276,808 127,722 205,649 172,878 128,901 1,197,566 635,150 123,243
Interest income 12,359 17,628 18,076 15,615 13,971 10,543 8,049 5,789 63,678 38,352 11,748
Interest expense (14,249) (14,548) (14,837) (14,868) (18,744) (18,686) (18,155) (16,886) (58,502) (72,471) (69,298)
Other income (expense), net 127,375 (31,747) 53,939 42,610 (90,452) (60,995) 53,819 96,838 192,177 (790) (81,382)
Income (loss) before provision for (benefit from) income taxes 676,950 70,666 327,138 320,165 32,497 136,511 216,591 214,642 1,394,919 600,241 (15,689)
(Benefit from) provision for income taxes 93,716 13,148 59,711 51,534 (1,492,599) 8,055 10,341 (12,659) 218,109 (1,486,862) (107,324)
Net income         1,525,096 128,456 206,250 227,301 1,176,810 2,087,103 91,635
Loss attributable to noncontrolling interest         25,431 290 1,110 (17,038) 0 9,793 171,849
Net income attributable to Vertex $ 583,234 $ 57,518 $ 267,427 $ 268,631 $ 1,550,527 $ 128,746 $ 207,360 $ 210,263 $ 1,176,810 $ 2,096,896 $ 263,484
Net income:                      
Basic (usd per share) $ 2.26 $ 0.22 $ 1.04 $ 1.05 $ 6.08 $ 0.51 $ 0.82 $ 0.83 $ 4.58 $ 8.24 $ 1.06
Diluted (usd per share) $ 2.23 $ 0.22 $ 1.03 $ 1.03 $ 5.97 $ 0.50 $ 0.80 $ 0.81 $ 4.51 $ 8.09 $ 1.04
Shares used in per share calculations:                      
Basic (in shares) 258,003 256,946 256,154 255,695 254,868 254,905 254,135 253,231 256,728 254,292 248,858
Diluted (in shares) 262,108 260,473 259,822 260,175 259,812 259,788 258,584 258,526 260,673 259,185 253,225
Product revenues, net                      
Revenues:                      
Product revenues, net $ 1,413,265 $ 949,828 $ 940,380 $ 857,253 $ 868,173 $ 782,511 $ 749,912 $ 637,729 $ 4,160,726 $ 3,038,325 $ 2,165,480
Collaborative and royalty revenues                      
Revenues:                      
Product revenues, net $ 0 $ 0 $ 913 $ 1,182 $ 1,933 $ 2,024 $ 2,245 $ 3,070 $ 2,095 $ 9,272 $ 323,172