Related Party Transactions - Additional Information (Details) - LTRIP - USD ($) shares in Millions	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Related Party Transaction [Line Items]
Beneficially ownership of shares of common stock	18.2
Percentage taken from outstanding shares of common stock	14.40%
Percentage of beneficially ownership of shares of common stock class B	22.30%
Right to voting	one vote per share
Beneficially ownership of equity securities	57.60%
Related party transactions	$ 0	$ 0
Class B Common Stock
Related Party Transaction [Line Items]
Beneficially ownership of shares of common stock	12.8
Percentage taken from outstanding shares of common stock	100.00%
Right to voting	Ten votes per share