Share-Based Compensation - Change in Number of BSPCE/OSA/RSU/BSA (Details)	3 Months Ended
	Mar. 31, 2020 shares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments [Roll Forward]
Beginning balance (in shares)	7,902,288
Granted (in shares)	126,674
Exercised (in shares)	(5,700)
Vested (in shares)	(640,528)
Forfeited (in shares)	(396,381)
Expired (in shares)	(3,600)
Ending balance (in shares)	6,982,753
OSA/BSPCE
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Beginning balance, options (in shares)	2,559,534
Granted, options (in shares)	0
Exercised, options (in shares)	(5,700)
Vested, options (in shares)	0
Forfeited, options (in shares)	(107,929)
Expired, options (in shares)	(3,600)
Ending balance, options (in shares)	2,442,305
RSU
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Beginning balance (in shares)	4,978,987
Granted (in shares)	126,674
Exercised (in shares)	0
Vested (in shares)	(640,528)
Forfeited (in shares)	(275,710)
Expired (in shares)	0
Ending balance (in shares)	4,189,423
BSAs
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Beginning balance, options (in shares)	363,767
Granted, options (in shares)	0
Exercised, options (in shares)	0
Vested, options (in shares)	0
Forfeited, options (in shares)	(12,742)
Expired, options (in shares)	0
Ending balance, options (in shares)	351,025