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STOCK-BASED COMPENSATION - Narrative (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
	Jan. 05, 2021	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Stock-based compensation
Stock-based compensation expense		$ 56,300	$ 40,000	$ 219,700	$ 69,600
Noncash stock-based compensation expense				133,577	69,599
Proceeds from stock options exercised				11,600	$ 10,900
Stock Plans
Stock-based compensation
Unrecognized compensation cost		433,200		$ 433,200
Weighted average period for recognition of cost				2 years 10 months 24 days
Thrive
Stock-based compensation
Stock-based compensation expense	$ 166,000
Noncash stock-based compensation expense		$ 1,000		$ 14,500
Accelerated vesting compensation expense	$ 65,000
Option Plan Shares \| Thrive
Stock-based compensation
Accelerated vesting (in shares)		4,982		103,996
Restricted Stock Units \| Thrive
Stock-based compensation
Accelerated vesting (in shares)		5,827		33,306