The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Goodwill and Intangible Assets - Narrative (Details) $ in Millions	3 Months Ended	12 Months Ended
	Sep. 30, 2020 USD ($)	Dec. 31, 2021 USD ($) market	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Business Acquisition [Line Items]
Amortization expense		$ 0.8	$ 0.7	$ 0.5
FCC spectrum licenses
Business Acquisition [Line Items]
Indefinite-lived intangible assets acquired	$ 16.1	$ 16.1
Number of markets included in transaction \| market		15
Indefinite-lived intangible assets, cost basis of assets included in transaction		$ 4.5