Property and Equipment and Software and Content Development Costs (Schedule of Property and Equipment) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 170,789	$ 170,020
Less: accumulated depreciation	(63,363)	(58,592)
Property and equipment, net	107,426	111,428
Land [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	9,548	9,548
Building [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 61,284	61,284
Property and equipment, estimated useful life (years)	39 years
Building improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 10,874	10,874
Building improvements [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life (years)	7 years
Building improvements [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life (years)	20 years
Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,312	2,320
Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life (years)	1 year
Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life (years)	5 years
Computer hardware [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 47,886	47,768
Computer hardware [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life (years)	1 year
Computer hardware [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life (years)	5 years
Computer software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 20,299	21,347
Computer software [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life (years)	1 year
Computer software [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life (years)	5 years
Construction in progress [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 3,500	2,135
Furniture and fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 3,264	2,658
Furniture and fixtures [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life (years)	2 years
Furniture and fixtures [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life (years)	7 years
Leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 11,822	$ 12,086

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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