CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net loss	$ (514,021)	$ (384,734)	$ (255,916)
Other comprehensive income (loss):
Unrealized gain (loss) on available-for-sale debt securities, net of tax of $1,148, $0 and $0, for the years ended December 31, 2019, 2018 and 2017, respectively	3,447	(132)	(342)
Less: amounts recognized for net realized gain included in net loss	(323)	(31)	(412)
Total other comprehensive income (loss)	3,124	(163)	(754)
Comprehensive loss	$ (510,897)	$ (384,897)	$ (256,670)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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