Discontinued Operations - Income (Loss) From Discontinued Operations (Details) - Big Fish Games - Discontinued Operations, Disposed of by Sale - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net revenue	$ 0.0	$ 0.0	$ 0.0	$ 0.0
Selling, general and administrative expense	0.0	0.3	0.0	1.5
Legal settlement	0.0	124.0	0.0	124.0
Loss from discontinued operations before benefit for income taxes	0.0	(124.3)	0.0	(125.5)
Income tax benefit	0.0	29.1	0.0	29.4
Loss from discontinued operations, net of tax	$ 0.0	$ (95.2)	$ 0.0	$ (96.1)

Disposal Group, Including Discontinued Operations, Transaction Expense

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Amount before tax of income (loss) from operations classified as a discontinued operation. Excludes gain (loss) on disposal and provision for gain (loss) until its disposal.

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Amount after tax of income (loss) from operations classified as a discontinued operation. Excludes gain (loss) on disposal and provision for gain (loss) until disposal.

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Amount of tax expense (benefit) attributable to income (loss) from operations classified as a discontinued operation. Excludes tax expense (benefit) for gain (loss) on disposal and for provision for gain (loss) until disposal.

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Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.

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