Liberty Broadband Corporation Quarterly report pursuant to Section 13 or 15(d)

Software Impairment (Details) - USD ($)	3 Months Ended		9 Months Ended
Software Impairment (Details) - USD ($)	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Software impairment charge	$ 0	$ 2,571,000	$ 0	$ 29,839,000
Wireless, Internet, Video, Local Service, and Long Distance Customer Billing Systems [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Fair Value of Capital Expenditures		0		0
Software impairment charge				20,700,000
Internally Developed Machine-To-Machine Billing System [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Software impairment charge		500,000		7,100,000
User Management Software [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Software impairment charge		$ 1,000,000		$ 1,000,000