XML 21 R1.htm IDEA: XBRL DOCUMENT v3.22.0.1
Cover Page - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2021
Feb. 14, 2022
Jun. 30, 2021
Cover [Abstract]      
Document Type 10-K    
Document Annual Report true    
Document Period End Date Dec. 31, 2021    
Current Fiscal Year End Date --12-31    
Document Transition Report false    
Entity File Number 001-32358    
Entity Registrant Name SPOK HOLDINGS, INC    
Entity Incorporation, State or Country Code DE    
Entity Tax Identification Number 16-1694797    
Entity Address, Address Line One 5911 Kingstown Village Pkwy, 6th Floor    
Entity Address, City or Town Alexandria    
Entity Address, State or Province VA    
Entity Address, Postal Zip Code 22315    
City Area Code 800    
Local Phone Number 611-8488    
Title of 12(b) Security Common Stock, par value $0.0001 per share    
Trading Symbol SPOK    
Security Exchange Name NASDAQ    
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Accelerated Filer    
Entity Small Business true    
Entity Emerging Growth Company false    
ICFR Auditor Attestation Flag false    
Entity Shell Company false    
Entity Public Float     $ 181
Entity Common Stock, Shares Outstanding (shares)   19,742,512  
Documents Incorporated by Reference Portions of the registrant’s Definitive Proxy Statement for the 2022 Annual Meeting of Stockholders of the registrant, which will be filed with the Securities and Exchange Commission pursuant to Regulation 14A no later than May 2, 2022, are incorporated by reference into Part III of this Report.    
Entity Central Index Key 0001289945    
Document Fiscal Year Focus 2021    
Document Fiscal Period Focus FY    
Amendment Flag false