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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

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- Definition

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

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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

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Fair value portion of investments accounted under the equity method.

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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.

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- Definition

Price of a single share of a number of saleable stocks of a company.

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FINANCIAL INSTRUMENTS - Fair Value of Liabilities Measured on a Recurring Basis (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	Jul. 10, 2020	Mar. 13, 2017	Jun. 30, 2020	Mar. 07, 2017
Fair Value Measurements
Closing sale price (in dollars per share)			$ 52.47
Myoscience Acquisition
Fair Value Measurements
Acquisition-related contingent consideration			$ 20,800
Convertible Senior Notes Due 2022
Fair Value Measurements
Closing sale price (in dollars per share)				$ 48.65
Initial conversion price of notes into common stock (in dollars per share)		$ 66.89
Convertible Senior Notes Due 2022 \| Maximum
Fair Value Measurements
Debt instrument, convertible, conversion premium (in shares)		5.2
Convertible Senior Notes Due 2022 \| Maximum \| Subsequent Event
Fair Value Measurements
Debt instrument, convertible, conversion premium (in shares)	2.4
Level 1
Fair Value Measurements
Equity Investments			10,032
Level 1 \| Myoscience Acquisition
Fair Value Measurements
Acquisition-related contingent consideration			0
Level 1 \| Convertible Senior Notes Due 2022
Fair Value Measurements
Convertible senior notes			0
Level 2
Fair Value Measurements
Equity Investments			0
Level 2 \| Myoscience Acquisition
Fair Value Measurements
Acquisition-related contingent consideration			0
Level 2 \| Convertible Senior Notes Due 2022
Fair Value Measurements
Convertible senior notes			378,206
Level 3
Fair Value Measurements
Equity Investments			0
Level 3 \| Myoscience Acquisition
Fair Value Measurements
Acquisition-related contingent consideration			20,830
Level 3 \| Convertible Senior Notes Due 2022
Fair Value Measurements
Convertible senior notes			0
Reported Value Measurement
Fair Value Measurements
Equity Investments			10,032
Reported Value Measurement \| Myoscience Acquisition
Fair Value Measurements
Acquisition-related contingent consideration			20,830
Reported Value Measurement \| Convertible Senior Notes Due 2022
Fair Value Measurements
Convertible senior notes			$ 314,182
Unsecured Debt \| Convertible Senior Notes Due 2022
Fair Value Measurements
Stated interest rate (as a percent)		2.375%	2.375%