Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2019	Dec. 31, 2018
Unbilled receivables	$ 559,553	$ 559,553	$ 673,616
Deferred revenue	9,516	9,516	$ 19,566
Contract balances, revenue recognized	1,800	17,900
Remaining performance obligations	$ 28,600	$ 28,600
Remaining performance obligations, expected timing of satisfaction period	2 years	2 years
Minimum
License agreement, term of agreement		1 year
Long-duration contracts, assumptions by product and guarantee, discount rate	3.00%	3.00%
Maximum
License agreement, term of agreement		7 years
Long-duration contracts, assumptions by product and guarantee, discount rate	6.00%	6.00%

License Agreement, Term of Agreement

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- Definition

Amount, before allowance for credit loss, of right to consideration in exchange for good or service transferred to customer, when right is conditioned on something other than passage of time.

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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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- Definition

Percentage discount rate used to calculate present value of an expected stream of future payments, which is included in the calculation of the amount of the specified guaranteed benefit obligation as of the balance sheet date.

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- Definition

Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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