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

Quarterly report pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Business and Summary of Significant Accounting Principles (Policies)
Notes Tables
Notes Details

Fair Value Measurements and Derivative Instruments Fair Value Measurements and Derivative Instruments (Derivative Financial Instruments) (Details)

v3.3.0.814

Fair Value Measurements and Derivative Instruments Fair Value Measurements and Derivative Instruments (Derivative Financial Instruments) (Details) - USD ($)		9 Months Ended
	Feb. 02, 2015	Sep. 30, 2015
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Stock Appreciation Rights, Expiration Date	8 years
Unsecured Debt [Member] \| Searchlight ALX, LP Promissory Note [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt face amount	$ 75,000,000.0
Stock Appreciation Rights (SARs) [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value measurement with unobservable inputs, beginning balance		$ 0
Issuance		21,660,000
Fair value adjustment at end of period, included in Other Income (Expense)		5,040,000
Fair value measurement with unobservable inputs, ending balance		$ 26,700,000
Stock Appreciation Rights (SARs) [Member] \| Common Stock - Class A [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Stock Appreciation Rights	3,000,000
Exercise price of stock appreciation rights (per share)	$ 13.00
Stock Appreciation Rights (SARs) [Member] \| Common Stock - Class A [Member] \| Searchlight ALX, LP Promissory Note [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Stock Appreciation Rights	3,000,000
Exercise price of stock appreciation rights (per share)	$ 13.00

- Definition

Stock Appreciation Rights, Expiration Date

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Number of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section S99

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Face (par) amount of debt instrument at time of issuance.

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-SubTopic 30

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of purchases, (sales), issuances and (settlements) of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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