Stockholders' Equity and Redeemable Preferred Equity - Narrative (Details)									3 Months Ended			6 Months Ended
	May 29, 2019 USD ($)	May 23, 2019 USD ($)	May 01, 2019 USD ($)	Mar. 05, 2019 USD ($)	Feb. 28, 2019 USD ($)	Dec. 19, 2018 USD ($) $ / shares shares	May 31, 2018 USD ($) $ / shares shares	Nov. 17, 2017 USD ($) shares	Jun. 30, 2019 USD ($) $ / shares shares	Mar. 31, 2019 USD ($) shares	Jun. 30, 2018 USD ($) shares	Jun. 30, 2019 USD ($) $ / shares shares	Jun. 30, 2018 USD ($) shares	Dec. 31, 2018 USD ($) $ / shares shares	Mar. 31, 2018 shares	Dec. 31, 2017 shares
Class of Stock [Line Items]
Common stock, shares authorized (in shares) | shares									750,000,000			750,000,000		750,000,000
Common stock, par value (in dollars per share)									$ 0.01			$ 0.01		$ 0.01
Preferred stock, shares authorized (in shares) | shares									20,000,000			20,000,000
Preferred stock, par value (in dollars per share)									$ 0.01			$ 0.01
Common shares dividend declared | $			$ 14,243,000	$ 14,218,000					$ 14,243,000	$ 14,218,000	$ 0	$ 28,500,000	$ 0
Common stock, shares outstanding (in shares) | shares									43,159,931			43,159,931		43,000,862
Shares authorized under share repurchase program | $														$ 50,000,000.0
Share repurchased during period (in shares) | shares												0
SMTA Preferred Shares
Class of Stock [Line Items]
Issuance of shares of preferred stock, net (in shares) | shares							6,000,000.0				6,000,000
Preferred stock liquidation preference | $							$ 150,000,000.0
Preferred stock dividend percentage rate							10.00%
Preferred stock, per share liquidation preference (in dollars per share)							$ 25.00		$ 25			$ 25		$ 25
Liquidation preference on a quarterly basis (in dollar per share)							0.625
Liquidation preference on an annual basis (in dollars per share)							$ 2.50
Preferred stock dividends paid | $			$ 3,750,000	$ 3,750,000					$ 3,800,000			$ 7,500,000
Preferred stock, shares outstanding (in shares) | shares									6,000,000	6,000,000	6,000,000	6,000,000	6,000,000	6,000,000	0	0
SubREIT Series A Preferred Stock
Class of Stock [Line Items]
Issuance of shares of preferred stock, net (in shares) | shares							5,000				5,000
Preferred stock liquidation preference | $							$ 5,000,000.0
Preferred stock dividend percentage rate							18.00%
Preferred stock, per share liquidation preference (in dollars per share)							$ 1,000.00
Liquidation preference on a quarterly basis (in dollar per share)							45.00
Liquidation preference on an annual basis (in dollars per share)							$ 180.00
Preferred stock dividends paid | $		$ 225,000			$ 225,000
Preferred stock, shares outstanding (in shares) | shares									5,125	5,125	5,000	5,125	5,000	5,125	0	0
SubREIT Preferred Shares
Class of Stock [Line Items]
Preferred stock, per share liquidation preference (in dollars per share)									$ 1,000			$ 1,000		$ 1,000
Preferred stock dividends paid | $									$ 233,000			$ 458,000
Preferred stock, shares outstanding (in shares) | shares									5,125			5,125		5,125
SubREIT Series B Preferred Stock
Class of Stock [Line Items]
Issuance of shares of preferred stock, net (in shares) | shares						125
Preferred stock liquidation preference | $						$ 125,000
Preferred stock dividend percentage rate						12.00%
Preferred stock, per share liquidation preference (in dollars per share)						$ 1,000.00
Liquidation preference on a quarterly basis (in dollar per share)						30.00
Liquidation preference on an annual basis (in dollars per share)						$ 120.00
Preferred stock dividends paid | $	$ 8,000
Spirit Realty Capital, Inc.
Class of Stock [Line Items]
Share issuance ratio							0.01
Common Shares
Class of Stock [Line Items]
Stock issued during period (in shares) | shares							42,851,010	10,000			42,851,010
Value of stock issued | $								$ 10,000			$ 429,000