Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
Current portion of deferred revenue	$ 5,697	$ 11,088
Current portion of long-term debt, including $31,211 and $0 to related parties as of December 31, 2019 and 2018, respectively	31,670	479
Long-term debt, less current portion	186,321	211,216
Long-term portion of deferred revenue	$ 48,136	$ 46,728
Common stock, shares authorized (in shares)	400,000,000	200,000,000
Common stock, shares issued (in shares)	163,274,880	160,020,466
Common stock, shares outstanding (in shares)	163,274,880	160,020,466
Related Parties, Aggregated
Related Party Transaction [Line Items]
Current portion of deferred revenue	$ 877	$ 6,502
Current portion of long-term debt, including $31,211 and $0 to related parties as of December 31, 2019 and 2018, respectively	31,211	0
Long-term debt, less current portion	25,000	55,290
Long-term portion of deferred revenue	$ 30,182	$ 44,772

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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