Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands		6 Months Ended
		Jun. 30, 2021	Jun. 30, 2020
Cash flows from operating activities:
Net income (loss)		$ 149,763	$ (97,760)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization		20,412	17,248
Stock-based compensation expense		83,083	60,441
Amortization of right-of-use assets		13,979	15,947
Amortization of content assets	[1]	28,093	12,182
Provision for (recoveries of) doubtful accounts		(1,099)	3,516
Other items, net		(8)	290
Changes in operating assets and liabilities:
Accounts receivable		(56,661)	21,372
Inventories		5,899	4,713
Prepaid expenses and other current assets		(30,235)	(5,222)
Other non-current assets		(72,195)	2,095
Accounts payable		16,433	20,847
Accrued liabilities		16,543	6,336
Operating lease liabilities		(18,394)	12,695
Other long-term liabilities		(527)	(556)
Deferred revenue		(10,326)	5,952
Net cash provided by operating activities		144,760	80,096
Cash flows from investing activities:
Purchases of property and equipment		(13,898)	(64,109)
Acquisitions of businesses, net of cash acquired		(136,778)
Proceeds from escrows associated with acquisition			1,058
Net cash used in investing activities		(150,676)	(63,051)
Cash flows from financing activities:
Proceeds from equity issued under at-the-market offerings, net of issuance costs		989,615	349,609
Proceeds from borrowings, net of issuance costs			69,325
Repayments of borrowings		(2,500)	(71,825)
Proceeds from equity issued under incentive plans		10,285	5,877
Net cash provided by financing activities		997,400	352,986
Net increase in cash, cash equivalents and restricted cash		991,484	370,031
Cash, cash equivalents and restricted cash —beginning of period		1,093,249	517,333
Cash, cash equivalents and restricted cash —end of period		2,084,733	887,364
Cash, cash equivalents and restricted cash at end of period:
Cash and cash equivalents		2,083,273	885,825
Restricted cash, current			1,539
Restricted cash, non-current		1,460
Cash, cash equivalents and restricted cash —end of period		2,084,733	887,364
Supplemental disclosures of cash flow information:
Cash paid for interest		1,290	2,118
Cash paid for income taxes		487	482
Supplemental disclosures of noncash investing and financing activities:
Non-cash consideration for business combination		15,200
Services to be received as part of a business combination		6,300
Unpaid portion of property and equipment purchases		3,709	5,218
Unpaid portion of acquisition-related expenses		$ 271
Unpaid portion of purchased intangibles			400
Unpaid portion of at-the-market issuance costs			$ 150

[1] Included in Cost of revenue, platform in the condensed consolidated statements of operations.