Derivative Instruments - Estimated Fair Values of Derivative Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Interest rate swap - notional amount $440 million
Derivative Instruments, Gain (Loss)
Contract/Notional Amount	$ 440,000	$ 440,000
Carrying Amount	(2,576)	(2,768)
Fair Value	$ (2,576)	$ (2,768)
Interest rate swap - notional amount $440 million | LIBOR
Derivative Instruments, Gain (Loss)
Derivative, basis spread on variable rate (maximum)	2.74%	2.74%
Interest rate swap - notional amount $200 million
Derivative Instruments, Gain (Loss)
Contract/Notional Amount	$ 200,000	$ 200,000
Carrying Amount	(1,172)	(1,259)
Fair Value	$ (1,172)	$ (1,259)
Interest rate swap - notional amount $200 million | LIBOR
Derivative Instruments, Gain (Loss)
Derivative, basis spread on variable rate (maximum)	2.74%	2.74%