Summary of Significant Accounting Policies - Change in estimate (Details) - Service Life - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2020	Dec. 31, 2019
Change in Accounting Estimate [Line Items]
Decrease to depreciation expense	$ 1,898		$ 4,511
Decrease to net loss	$ 1,533		$ 3,687
Decrease to loss per share	$ 0.02		$ 0.05
Video gaming terminals and equipment
Change in Accounting Estimate [Line Items]
Useful life		10 years	10 years	7 years

Change In Accounting Estimate, Increase (Decrease) Depreciation Expense

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- Definition

Change In Accounting Estimate, Increase (Decrease) Net Income (Loss)

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Change In Accounting Estimate, Increase (Decrease) To Net Loss Per Share

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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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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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