Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents, and restricted cash	$ 7,180,046	$ 5,178,187	$ 5,043,786	$ 5,028,205	$ 3,370,097	$ 3,812,041
Cash and cash equivalents
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents, and restricted cash	7,153,248		5,018,437
Other Current Assets
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents, and restricted cash	2,483		1,863
Non-current Assets
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents, and restricted cash	24,315		23,486
Cash
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents, and restricted cash	3,007,013		3,127,549
Cash | Cash and cash equivalents
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents, and restricted cash	2,980,468		3,103,525
Cash | Other Current Assets
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents, and restricted cash	2,483		1,863
Cash | Non-current Assets
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents, and restricted cash	24,062		22,161
Level 1 Securities | Money market funds
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents, and restricted cash	3,873,033		1,616,237
Level 1 Securities | Money market funds | Cash and cash equivalents
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents, and restricted cash	3,872,780		1,614,912
Level 1 Securities | Money market funds | Other Current Assets
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents, and restricted cash	0		0
Level 1 Securities | Money market funds | Non-current Assets
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents, and restricted cash	253		1,325
Level 2 Securities | Foreign Time Deposits
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents, and restricted cash	300,000		300,000
Level 2 Securities | Foreign Time Deposits | Cash and cash equivalents
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents, and restricted cash	300,000		300,000
Level 2 Securities | Foreign Time Deposits | Other Current Assets
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents, and restricted cash	0		0
Level 2 Securities | Foreign Time Deposits | Non-current Assets
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents, and restricted cash	$ 0		$ 0