Annual report pursuant to Section 13 and 15(d)

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

v3.3.1.900
Fair Value Measurements and Derivative Instruments Fair Value Measurements and Derivative Instruments (Derivative Financial Instruments) (Details) - USD ($)
 12 Months Ended
Feb. 02, 2015
Dec. 31, 2015
Dec. 31, 2014
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]      
Stock Appreciation Rights, Expiration Date 8 years    
Fair Value Assumptions, Expected Volatility Rate   40.00%  
Fair Value Assumptions, Risk Free Interest Rate   2.10%  
Unsecured Debt [Member] | Searchlight ALX, LP Promissory Note [Member]      
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]      
Face amount of debt $ 75,000,000.0    
Stock Appreciation Rights (SARs)      
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]      
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value   $ 32,820,000 $ 0
Issuance   21,660,000  
Stock Appreciation Rights (SARs) | Other Nonoperating Income (Expense) [Member]      
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]      
Fair value adjustment at end of period, included in Other Income (Expense)   $ 11,160,000  
Class A Common Stock | Stock Appreciation Rights (SARs)      
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]      
Rights outstanding 3,000,000    
Exercise price of rights $ 13.00    
Class A Common Stock | Stock Appreciation Rights (SARs) | Searchlight ALX, LP Promissory Note [Member]      
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]      
Rights outstanding 3,000,000    
Exercise price of rights $ 13.00    
Minimum      
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]      
Fair Value Assumptions, Expected Term   4 years  
Maximum      
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]      
Fair Value Assumptions, Expected Term   8 years