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Term of semiconductor product licenses.

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The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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Amount of cash outflow for taxes classified as other.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

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Summary Of Significant Accounting Policies - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Amortization		$ 49,766	$ 50,847	$ 58,149
Provisions for doubtful accounts		1,474	2,009	1,304
Net foreign exchange (losses) gains		(1,935)	77	486
Income tax provision		136,443	114,679	104,244
Net cash provided by (used in) operating activities		430,438	365,980	375,699
Net cash provided by (used in) financing activities		(294,651)	$ (288,630)	$ (299,927)
Minimum [Member]
Cumulative effect of new accounting principle in period of adoption		$ 165,000
Semiconductor product licenses, term		24 months
Property and equipment, estimated useful lives (years)		1 year
Maximum [Member]
Cumulative effect of new accounting principle in period of adoption		$ 190,000
Semiconductor product licenses, term		36 months
Property and equipment, estimated useful lives (years)		40 years
Customer Concentration Risk [Member]
Number of customers with more than five percent of revenue		0	0	0
Scenario, Forecast [Member] \| Minimum [Member]
Payments for other taxes	$ 15,000
Scenario, Forecast [Member] \| Maximum [Member]
Payments for other taxes	$ 20,000
Gross Impact [Member] \| Minimum [Member]
Cumulative effect of new accounting principle in period of adoption		$ 230,000
Gross Impact [Member] \| Maximum [Member]
Cumulative effect of new accounting principle in period of adoption		260,000
Adjustments for New Accounting Pronouncement [Member]
Income tax provision		$ (13,300)
Net cash provided by (used in) operating activities			$ 0	$ 0
Net cash provided by (used in) financing activities			$ 0	$ 0