Property and Equipment and Software and Content Development Costs (Schedule of Property and Equipment) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 172,387	$ 170,789
Less: accumulated depreciation	(73,698)	(63,363)
Property and equipment, net	98,689	107,426
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	$ 11,720	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	$ 2,646	2,312
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	$ 50,064	47,886
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	$ 21,982	20,299
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	$ 1,611	3,500
Furniture and fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 3,187	3,264
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	$ 10,345	$ 11,822

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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