Derivative Financial Instruments - Summary of Fair Value of Interest Rate Related Derivative Financial Instruments and Their Classification on Condensed Consolidated Balance Sheets (Details) - Designated as Hedging Instrument - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Other Current Assets
Derivative [Line Items]
Fair value of derivative instruments, asset derivatives	$ 1,639	$ 486
Other Assets
Derivative [Line Items]
Fair value of derivative instruments, asset derivatives	$ 5,530	$ 3,398