Discontinued Operations - Income (Loss) From Discontinued Operations (Details) - Big Fish Games - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
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	0.3	1.6	1.5	2.0
Legal settlement	124.0	0.0	124.0	0.0
Loss from discontinued operations before provision for income taxes	(124.3)	(1.6)	(125.5)	(2.0)
Income tax benefit	29.1	0.4	29.4	0.5
Loss from discontinued operations, net of tax	$ (95.2)	$ (1.2)	$ (96.1)	$ (1.5)

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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 general and administrative expense attributable to disposal group, including, but not limited to, discontinued operation.

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