Debt, Net - Conversion and EPS Impact of Convertible Notes Hedging Transactions (Details) - Convertible Notes $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($) $ / shares
2020 Convertible Notes
Debt Instrument [Line Items]
Cost of the hedge transaction(s) | $	$ 18,113
Conversion price (USD per share)	$ 45.72
2020 Convertible Notes | Hedging of Convertible Debt Instrument
Debt Instrument [Line Items]
Conversion price (USD per share)	$ 61.55
2021 Convertible Notes
Debt Instrument [Line Items]
Cost of the hedge transaction(s) | $	$ 19,545
Conversion price (USD per share)	$ 59.39
2021 Convertible Notes | Hedging of Convertible Debt Instrument
Debt Instrument [Line Items]
Conversion price (USD per share)	$ 83.14
2023 Exchangeable Notes
Debt Instrument [Line Items]
Cost of the hedge transaction(s) | $	$ 17,785
Conversion price (USD per share)	$ 44.62
2023 Exchangeable Notes | Hedging of Convertible Debt Instrument
Debt Instrument [Line Items]
Conversion price (USD per share)	$ 62.48