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

Quarterly report pursuant to Section 13 or 15(d)

Long-Term Debt (Details)

Long-Term Debt (Details) - USD ($)			3 Months Ended		9 Months Ended
Long-Term Debt (Details) - USD ($)	Apr. 01, 2015	Feb. 02, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Debt Instrument [Line Items]
Loan fees and other expenses					$ 13,979,000	$ 0
Loss on extinguishment of debt			$ 0	$ 0	27,700,000	0
Payment of debt call premiums					$ 20,244,000	$ 0
Medium-term Notes [Member] \| Amended Senior Credit Facility [Member]
Debt Instrument [Line Items]
Debt face amount		$ 275,000,000.0
Percentage of principal payable		0.25%
Loan fees and other expenses		$ 6,200,000
Medium-term Notes [Member] \| Amended Senior Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Spread on variable rate		3.25%
Interest rate floor		0.75%
Unsecured Debt [Member] \| Searchlight ALX, LP Promissory Note [Member]
Debt Instrument [Line Items]
Debt face amount		$ 75,000,000.0
Debt stated percentage		7.50%
Redemption price (percentage)					50.00%
Debt issuance price, percent		100.00%
Unamortized discount		$ 21,700,000
Senior Notes [Member] \| Senior Notes 6.875 Percent due 2025 [Member]
Debt Instrument [Line Items]
Debt face amount	$ 450,000,000
Debt stated percentage	6.875%
Debt issuance price, percent	99.105%
Repayments of debt	$ 425,000,000
Purchase price of debt in occurance of change of control, percentage of principal amount	101.00%
Purchase price in event of an asset sale, percentage of principal	100.00%
Issuance cost	$ 7,900,000
Senior Notes [Member] \| Senior Notes Due 2021
Debt Instrument [Line Items]
Debt stated percentage	6.75%
Senior Notes [Member] \| Senior Notes Due 2019
Debt Instrument [Line Items]
Loss on extinguishment of debt					$ 27,700,000
Payment of debt call premiums					20,200,000
Write off of deferred debt issuance costs					5,400,000
Write off of debt discount					$ 2,100,000
Common Stock - Class A [Member] \| Stock Appreciation Rights (SARs) [Member]
Debt Instrument [Line Items]
Stock Appreciation Rights		3,000,000
Stock Appreciation Rights issued for interest capitalization (percent)		4.00%
Exercise price of stock appreciation rights (per share)		$ 13.00
Common Stock - Class A [Member] \| Stock Appreciation Rights (SARs) [Member] \| Searchlight ALX, LP Promissory Note [Member]
Debt Instrument [Line Items]
Stock Appreciation Rights		3,000,000
Exercise price of stock appreciation rights (per share)		$ 13.00