Cumulative Other Comprehensive Loss - Schedule of Amounts Recognized in Cumulative Other Comprehensive Loss (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Amounts recognized in cumulative other comprehensive income (Loss) by component
Balance as of beginning of period	$ 3,183,998
Balance as of end of period	3,391,561
Unrealized Gain (Loss) on Marketable Securities
Amounts recognized in cumulative other comprehensive income (Loss) by component
Balance as of beginning of period	(342)
Other comprehensive income before reclassifications	342
Net current period other comprehensive income	342
Balance as of end of period	$ 0

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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