The price per share of the conversion feature embedded in the debt instrument.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031898-161870

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Net Income Per Share (Narrative) (Details) - Convertible Debt - $ / shares	Apr. 03, 2020	Mar. 10, 2020	Mar. 05, 2020	Feb. 04, 2020	Feb. 03, 2020	Jan. 31, 2020	Nov. 11, 2019	Aug. 01, 2016	Mar. 04, 2016
2.5% Convertible Senior Notes due April 1, 2021
Debt Instrument [Line Items]
Conversion price (in usd per share)					$ 16.77				$ 16.77
Stated interest rate (as a percent)				2.50%	2.50%		2.50%		2.50%
2.0% Convertible Senior Notes due August 15, 2021
Debt Instrument [Line Items]
Conversion price (in usd per share)					$ 20.41			$ 20.41
Stated interest rate (as a percent)				2.00%	2.00%		2.00%	2.00%
New 2.5% Convertible Senior Notes due April 1, 2022
Debt Instrument [Line Items]
Conversion price (in usd per share)				$ 16.77
Stated interest rate (as a percent)	2.50%			2.50%			2.50%
New 2.0% Convertible Senior Notes due August 15, 2022
Debt Instrument [Line Items]
Conversion price (in usd per share)				$ 20.41
Stated interest rate (as a percent)	2.00%			2.00%			2.00%
2.5% Convertible Senior Notes due April 1, 2022
Debt Instrument [Line Items]
Conversion price (in usd per share)			$ 19	$ 8.40		$ 8.40
Stated interest rate (as a percent)	2.50%	2.50%	2.50%	2.50%			2.50%
2.0% Convertible Senior Notes due August 15, 2022
Debt Instrument [Line Items]
Conversion price (in usd per share)				$ 10.23		$ 10.23
Stated interest rate (as a percent)	2.00%			2.00%			2.00%