| Cover Page Document | Jul. 28, 2021 |
| Cover [Abstract] | |
| Entity Incorporation, State or Country Code | DE |
| Document Type | 8-K |
| Entity Registrant Name | SPOK HOLDINGS, INC |
| Entity File Number | 001-32358 |
| 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 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, par value $0.0001 per share |
| Trading Symbol | SPOK |
| Entity Emerging Growth Company | false |
| Amendment Flag | false |
| Entity Central Index Key | 0001289945 |
| Security Exchange Name | NASDAQ |
| Document Period End Date | Jul. 28, 2021 |
