Goodwill and Intangible Assets - Summary of Goodwill (Detail) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Indefinite Lived Intangible Assets By Major Class [Line Items] | |||
| Balance as of December 31, 2015 | $ 12,005 | ||
| Goodwill acquired | 16,922 | ||
| Goodwill impairment | (13,021) | $ 0 | $ 0 |
| Foreign currency translation adjustments | (2,067) | ||
| Balance as of December 31, 2016 | 13,839 | 12,005 | |
| CareDx [Member] | |||
| Indefinite Lived Intangible Assets By Major Class [Line Items] | |||
| Balance as of December 31, 2015 | 12,005 | ||
| Goodwill acquired | 0 | ||
| Goodwill impairment | 0 | ||
| Foreign currency translation adjustments | 0 | ||
| Balance as of December 31, 2016 | 12,005 | 12,005 | |
| Allenex [Member] | |||
| Indefinite Lived Intangible Assets By Major Class [Line Items] | |||
| Balance as of December 31, 2015 | 0 | ||
| Goodwill acquired | 16,922 | ||
| Goodwill impairment | (13,021) | ||
| Foreign currency translation adjustments | (2,067) | ||
| Balance as of December 31, 2016 | $ 1,834 | $ 0 | |