Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and restricted cash	$ 5,043,786	$ 3,812,041	$ 2,822,795	$ 1,467,576
Cash
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and restricted cash	3,127,549	2,588,945
Level 1 securities | Money market funds
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and restricted cash	1,616,237	1,223,096
Level 2 securities | Foreign Time Deposits
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and restricted cash	300,000
Cash and cash equivalents
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and restricted cash	5,018,437	3,794,483
Cash and cash equivalents | Cash
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and restricted cash	3,103,525	2,572,685
Cash and cash equivalents | Level 1 securities | Money market funds
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and restricted cash	1,614,912	1,221,798
Cash and cash equivalents | Level 2 securities | Foreign Time Deposits
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and restricted cash	300,000
Other Current Assets
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and restricted cash	1,863
Other Current Assets | Cash
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and restricted cash	1,863
Other Current Assets | Level 1 securities | Money market funds
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and restricted cash	0
Other Current Assets | Level 2 securities | Foreign Time Deposits
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and restricted cash	0
Non-current Assets
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and restricted cash	23,486	17,558
Non-current Assets | Cash
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and restricted cash	22,161	16,260
Non-current Assets | Level 1 securities | Money market funds
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and restricted cash	1,325	$ 1,298
Non-current Assets | Level 2 securities | Foreign Time Deposits
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents and restricted cash	$ 0