Consolidated Financial Statements' Components - Depreciation, Amortization and Accretion (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Depreciation	$ 6,197	$ 7,727	$ 8,176
Amortization	2,500	2,500	2,886
Accretion	552	542	562
Total depreciation, amortization and accretion expense	9,249	10,769	11,624
Leasehold improvements
Property, Plant and Equipment [Line Items]
Depreciation	63	232	234
Asset retirement costs
Property, Plant and Equipment [Line Items]
Depreciation	(766)	(300)	(388)
Paging and computer equipment
Property, Plant and Equipment [Line Items]
Depreciation	6,526	7,397	8,024
Furniture, fixtures and vehicles
Property, Plant and Equipment [Line Items]
Depreciation	$ 374	$ 398	$ 306

The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

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-Publisher FASB
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- Definition

Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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The aggregate net amount of depreciation, amortization, and accretion recognized during an accounting period. As a noncash item, the net amount is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

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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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No definition available.

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