Fair Value Measurements (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Financial liability recorded at fair value on a recurring basis [Abstract]
Interest rate swaps	$ (47)	$ (221)
Fixed-rate debt on Consolidated Balance Sheets
Fixed-rate debt outstanding [abstract]
Fixed-rate debt	1,718	1,855
Estimated fair value of fixed-rate debt
Fixed-rate debt outstanding [abstract]
Fixed-rate debt	1,746	1,915
Recurring
Financial liability recorded at fair value on a recurring basis [Abstract]
Interest rate swaps	(47)	(221)
Recurring | Level 1
Financial liability recorded at fair value on a recurring basis [Abstract]
Interest rate swaps	0	0
Recurring | Level 2
Financial liability recorded at fair value on a recurring basis [Abstract]
Interest rate swaps	(47)	(221)
Recurring | Level 3
Financial liability recorded at fair value on a recurring basis [Abstract]
Interest rate swaps	$ 0	$ 0