Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2018	Oct. 19, 2018
Document Document And Entity Information [Abstract]
Entity Registrant Name	Spok Holdings, Inc
Entity Central Index Key	0001289945
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding (shares)		19,456,066
Entity Small Business	false
Entity Emerging Growth Company	false