Noncontrolling Interest - Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Reconciliation for equity attributable to noncontrolling interests
Balance at the beginning of period			$ 684,231
Net loss	$ (157,715)	$ (60,680)	(262,831)	$ (111,303)
Issuance of ordinary shares in follow-on offering, net of transaction costs			757,587
Share-based compensation			36,037
Exercise of options			10,582
Adjustment to opening balance of equity			(2,291)
Other comprehensive income, net of tax of nil:
Foreign currency translation adjustments	2,033	554	2,305	644
Unrealized holding gain, net	719	$ 19	1,048	$ 7
Net-current period other comprehensive income			3,353
Balance at the end of period	1,226,668		1,226,668
BeiGene, Ltd. Shareholder's Equity
Reconciliation for equity attributable to noncontrolling interests
Balance at the beginning of period			669,809
Net loss			(261,483)
Issuance of ordinary shares in follow-on offering, net of transaction costs			757,587
Share-based compensation			36,037
Exercise of options			10,582
Adjustment to opening balance of equity			(2,666)
Other comprehensive income, net of tax of nil:
Foreign currency translation adjustments			2,283
Unrealized holding gain, net			1,048
Net-current period other comprehensive income			3,331
Balance at the end of period	1,213,197		1,213,197
Non-controlling Interests
Reconciliation for equity attributable to noncontrolling interests
Balance at the beginning of period			14,422
Net loss			(1,348)
Adjustment to opening balance of equity			375
Other comprehensive income, net of tax of nil:
Foreign currency translation adjustments			22
Net-current period other comprehensive income			22
Balance at the end of period	$ 13,471		$ 13,471