| Document and Entity Information - USD ($) $ in Millions | 12 Months Ended | ||
| Dec. 31, 2015 | Mar. 14, 2016 | Jun. 30, 2015 | |
| Entity Information [Line Items] | |||
| Entity Registrant Name | Alphatec Holdings, Inc. | ||
| Entity Central Index Key | 1,350,653 | ||
| Current Fiscal Year End Date | --12-31 | ||
| Entity Filer Category | Accelerated Filer | ||
| Document Type | 10-K | ||
| Trading Symbol | ATEC | ||
| Document Period End Date | Dec. 31, 2015 | ||
| Document Fiscal Year Focus | 2,015 | ||
| Document Fiscal Period Focus | FY | ||
| Amendment Flag | false | ||
| Entity Well-known Seasoned Issuer | No | ||
| Entity Current Reporting Status | Yes | ||
| Entity Voluntary Filers | No | ||
| Entity Common Stock, Shares Outstanding | 102,150,232 | ||
| Entity Public Float | $ 88.1 |
