Derivative Instruments - Net Gains and Losses on Derivatives (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized (loss) gain on interest rate hedges	$ (8,016)	$ 420	$ 1,808
Interest Rate Swap
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized (loss) gain on interest rate hedges	$ (8,016)	$ 420	$ 1,808