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Goodwill and Intangible Assets (Narrative) (Details) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($) reportingUnit	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)
Finite-Lived Intangible Assets [Line Items]
Goodwill impairment loss	$ 56,850	$ 27,369	$ 56,850	$ 27,369
Goodwill	1,539,663		1,539,663		$ 1,591,474
Amortization expense	33,000	36,300	100,000	119,300
Digital Media
Finite-Lived Intangible Assets [Line Items]
Goodwill impairment loss			84,200		27,400
Digital Media \| Operating Segments
Finite-Lived Intangible Assets [Line Items]
Goodwill impairment loss	56,900	27,400	56,850	27,400
Goodwill	1,014,681		1,014,681		$ 1,065,989
Digital Media \| Operating Segments \| Digital Media Subsegment
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 79,200	$ 86,900	$ 79,200	$ 86,900
Number of reporting units \| reportingUnit		2