CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Unaudited) - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Class A and B common stock	Additional paid-in	Additional paid-in Cumulative Effect, Period of Adoption, Adjustment	Accumulated other comprehensive income (loss)	Accumulated deficit	Accumulated deficit Cumulative Effect, Period of Adoption, Adjustment
Beginning balance (in shares) at Dec. 31, 2019			432,796,720
Beginning balance at Dec. 31, 2019	$ 1,715,050		$ 0	$ 2,223,749		$ 1,629	$ (510,328)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(105,891)						(105,891)
Shares issued in connection with employee stock plans (in shares)			5,222,525
Shares issued in connection with employee stock plans	31,406			31,406
Issuance of common stock in connection with business combination (in shares)			357,017
Issuance of common stock in connection with business combination	14,999			14,999
Change in other comprehensive loss	(5,061)					(5,061)
Share-based compensation	79,562			79,562
Tax withholding related to vesting of restricted stock units (in shares)			(722,606)
Tax withholding related to vesting of restricted stock units	(48,772)			(48,772)
Conversion feature of convertible senior notes, due 2025, net of allocated costs	152,258			152,258
Purchase of bond hedges in conjunction with issuance of convertible senior notes, due 2025	(149,200)			(149,200)
Sale of warrants in conjunction with issuance of convertible senior notes, due 2025	99,500			99,500
Issuance of common stock in conjunction with the conversion of senior notes (in shares)			1,109,980
Issuance of common stock in conjunction with the conversion of senior notes	24,094			24,094
Ending balance (in shares) at Mar. 31, 2020			438,763,636
Ending balance at Mar. 31, 2020	1,807,945		$ 0	2,427,596		(3,432)	(616,219)
Beginning balance (in shares) at Dec. 31, 2019			432,796,720
Beginning balance at Dec. 31, 2019	1,715,050		$ 0	2,223,749		1,629	(510,328)
Ending balance (in shares) at Dec. 31, 2020			456,184,776
Ending balance at Dec. 31, 2020	$ 2,681,569	$ (399,734)	$ 0	2,955,464	$ (502,708)	23,328	(297,223)	$ 102,974
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accounting Standards Update [Extensible List]	mic:AccountingStandardsUpdate202006Member
Net income (loss)	$ 39,008						39,008
Shares issued in connection with employee stock plans (in shares)			4,311,094
Shares issued in connection with employee stock plans	32,891			32,891
Change in other comprehensive loss	(13,129)					(13,129)
Share-based compensation	121,965			121,965
Tax withholding related to vesting of restricted stock units (in shares)			(669,076)
Tax withholding related to vesting of restricted stock units	(152,013)			(152,013)
Issuance of common stock in conjunction with the conversion of senior notes (in shares)			166,967
Issuance of common stock in conjunction with the conversion of senior notes	3,816			3,816
Exercise of bond hedges in conjunction with the conversion of senior notes, due 2022 (in shares)			(5,325,320)
Ending balance (in shares) at Mar. 31, 2021			454,668,441
Ending balance at Mar. 31, 2021	$ 2,314,373		$ 0	$ 2,459,415		$ 10,199	$ (155,241)