Description of Business and Presentation of Financial Statements - Additional Information (Details) (USD $)	0 Months Ended	3 Months Ended		0 Months Ended
	Feb. 04, 2015 Director	Mar. 31, 2015	Mar. 31, 2014	Mar. 09, 2015	Dec. 31, 2014	Jan. 29, 2015
Description Of Business And Presentation Of Financial Statements [Line Items]
Business combination, assets assumed, marketable securities		$ 1,100,000
Business combination, liabilities assumed, notes payable		1,000,000
Proceeds from sale of marketable securities		1,065,000
Realized gain on sale of marketable securities		66,000
Percentage of partnership units outstanding		71.90%
Common stock, shares issued under IPO		43,565,495
Net proceeds from issuance of common stock upon initial public offering	172,400,000	493,722,000
Contributed to the operating partnership	323,200,000		1,171,000
Offering expenses		6,300,000
Number of directors	7
Members capital, shares issued					35,053,186
Common Class A
Description Of Business And Presentation Of Financial Statements [Line Items]
Common shares received	19,617,755
Common Class C
Description Of Business And Presentation Of Financial Statements [Line Items]
Common shares received	25,145
LTIP Units
Description Of Business And Presentation Of Financial Statements [Line Items]
Operating partnership issued	28,000
Revolving Credit Facility
Description Of Business And Presentation Of Financial Statements [Line Items]
Repayments of outstanding revolving credit facility		72,000,000
Sharyland Distribution & Transmission Services | Revolving Credit Facility
Description Of Business And Presentation Of Financial Statements [Line Items]
Repayments of outstanding revolving credit facility		150,000,000
InfraREIT, L.L.C.
Description Of Business And Presentation Of Financial Statements [Line Items]
Common stock, shares issued under IPO	1,700,000
Common stock sold under IPO, per share	$ 21.551
Contributed to the operating partnership	323,200,000
Partners capital received	8,000,000
Members capital, shares issued	15,000,000
Common stock conversion basis		one-for-one basis
InfraREIT, L.L.C. | Common Class A
Description Of Business And Presentation Of Financial Statements [Line Items]
Common shares received	19,617,755
InfraREIT, L.L.C. | Common Class C
Description Of Business And Presentation Of Financial Statements [Line Items]
Common shares received	25,145
InfraREIT, L.L.C. | LTIP Units
Description Of Business And Presentation Of Financial Statements [Line Items]
Common shares received				11,264
Common stock conversion basis		one-to-one basis
InfraREIT, L.L.C. | Operating Partnership Unit
Description Of Business And Presentation Of Financial Statements [Line Items]
Reverse share split						0.938550
Hunt-InfraREIT
Description Of Business And Presentation Of Financial Statements [Line Items]
Common stock, shares issued under IPO	1,551,878					1,700,000
Non-cash expense		44,900,000
Operating partnership issued	1,167,287
Common shares received				2,329,283
Hunt-InfraREIT | CREZ Project
Description Of Business And Presentation Of Financial Statements [Line Items]
Operating partnership issued	983,814
Hunt-InfraREIT | Operating Partnership Unit
Description Of Business And Presentation Of Financial Statements [Line Items]
Common shares received	1,551,878
MC Transmission Holdings Inc. | Operating Partnership Unit
Description Of Business And Presentation Of Financial Statements [Line Items]
Shares purchased consideration for promissory note	3,325,874
Initial Public Offering
Description Of Business And Presentation Of Financial Statements [Line Items]
Common stock, shares issued under IPO	23,000,000
Common stock sold under IPO, per share	$ 23.00
Net proceeds from issuance of common stock upon initial public offering	529,000,000
Hunt Consolidated Incorporation
Description Of Business And Presentation Of Financial Statements [Line Items]
Percentage of partnership units outstanding		28.10%
Repayments of related party debt		1,000,000
Westwood Trust
Description Of Business And Presentation Of Financial Statements [Line Items]
Shares purchased consideration for promissory note	6,242,999
Principal amount of shares purchased consideration for promissory note	$ 66,500,000