Convertible Senior Notes - Prepaid Forward Stock Purchase (Narrative) (Details) - USD ($) shares in Millions, $ in Millions		1 Months Ended
Jun. 03, 2020	Jun. 30, 2015
Debt Disclosure [Abstract]
Payments pursuant to prepaid forwards		$ 150.0
Stock repurchased and retired during period shares (in shares)	1.6
Antidilutive securities excluded from net loss per share (in shares)	1.8

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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-Publisher FASB
-Name Accounting Standards Codification
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