Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of capitalized and expensed compensation cost from equity-based compensation arrangements.

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-- None. No documentation exists for this element. --

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Stock-based Compensation Expense and Share Repurchase - (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Stock-based compensation expense:
Stock-based compensation expense related to inventories	$ 91	$ (678)	$ (454)	$ (2,001)
Total stock-based compensation included in costs and expenses	85,532	74,456	246,104	216,990
Cost of sales
Stock-based compensation expense:
Total stock-based compensation included in costs and expenses	1,259	686	3,263	1,656
Research and development expenses
Stock-based compensation expense:
Total stock-based compensation included in costs and expenses	52,918	46,186	153,018	134,855
Sales, general and administrative expenses
Stock-based compensation expense:
Total stock-based compensation included in costs and expenses	31,355	27,584	89,823	80,479
Stock options
Stock-based compensation expense:
Share-based compensation expense by type of award	27,234	25,969	81,880	80,865
Type of award:
Unrecognized Expense	189,045		$ 189,045
Weighted-average Recognition Period			2 years 9 months 7 days
Restricted stock and restricted stock units (including PSUs)
Stock-based compensation expense:
Share-based compensation expense by type of award	55,482	46,737	$ 157,397	131,388
Type of award:
Unrecognized Expense	388,909		$ 388,909
Weighted-average Recognition Period			2 years 8 months 16 days
ESPP share issuances
Stock-based compensation expense:
Share-based compensation expense by type of award	2,725	$ 2,428	$ 7,281	$ 6,738
Type of award:
Unrecognized Expense	$ 3,051		$ 3,051
Weighted-average Recognition Period			5 months 19 days