CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Statement [Abstract]
Lease revenue	$ 48,926	$ 51,618	$ 142,409	$ 131,664
Operating costs and expenses
General and administrative expense	6,787	6,718	19,506	19,565
Depreciation	12,063	13,328	35,632	38,997
Total operating costs and expenses	18,850	20,046	55,138	58,562
Income from operations	30,076	31,572	87,271	73,102
Other (expense) income
Interest expense, net	(10,120)	(10,357)	(31,864)	(30,196)
Other income, net	7	331	1,114	351
Total other expense	(10,113)	(10,026)	(30,750)	(29,845)
Income before income taxes	19,963	21,546	56,521	43,257
Income tax expense (benefit)	257	308	(4,885)	873
Net income	19,706	21,238	61,406	42,384
Less: Net income attributable to noncontrolling interest	5,435	5,908	16,937	11,797
Net income attributable to InfraREIT, Inc.	$ 14,271	$ 15,330	$ 44,469	$ 30,587
Net income attributable to InfraREIT, Inc. common stockholders per share:
Basic	$ 0.32	$ 0.35	$ 1.01	$ 0.70
Diluted	0.32	0.35	1.01	0.70
Cash dividends declared per common share	$ 0.25	$ 0.25	$ 0.75	$ 0.75