Subsequent Events (Details Narrative) - USD ($)						6 Months Ended
	Aug. 02, 2017	Jul. 31, 2017	Jul. 27, 2017	Jul. 26, 2017	Jun. 15, 2017	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Proceeds from issuance of offering						$ 22,527,507	$ 0
Net proceeds from issuance of shares						$ 0	$ 49,120,853
Common stock shares authorized						85,000,000		75,000,000
Excess stock, shares authorized						3,000,000		3,000,000
Preferred stock redemption amount						$ 91,595,000		$ 91,595,000
Mortgage loan						311,303,776		$ 293,025,592
Lines of credit paid down						$ 35,000,000
6.75% Series C Cumulative Redeemable Preferred Stock [Member]
Excess stock, shares authorized						3,000,000
Series C Preferred Stock [Member]
Preferred stock, redemption price per share						$ 25.00
Number of stock sold during period						5,000,000
Common stock shares authorized						110,000,000
Series C Preferred Stock [Member] | Maryland State Department of Assessments and Taxation [Member]
Increase in authorized number of shares						30,750,000
Excess stock, shares authorized						95,663,800
8.25% Series A Cumulative Redeemable Preferred Stock [Member]
Record date of dividend					May 15, 2017
8.0% Series B Cumulative Redeemable Preferred Stock [Member]
Excess stock, shares authorized						3,000,000
Record date of dividend					May 15, 2017
Subsequent Event [Member]
Mortgage loan			$ 1,200,000
Maturity date			Aug. 31, 2017
Lines of credit paid down		$ 35,000,000
Subsequent Event [Member] | 6.75% Series C Cumulative Redeemable Preferred Stock [Member]
Cumulative redeemable preferred stock, shares issued				5,000,000
Preferred stock, redemption price per share				$ 25.00
Number of stock sold during period				5,000,000
Proceeds from issuance of offering				$ 120,800,000
Cumulative redeemable preferred stock, shares authorized				5,750,000
Excess stock, shares authorized				3,000,000
Subsequent Event [Member] | Series C Preferred Stock [Member]
Exercised overallotment option and purchased additional shares	750,000
Net proceeds from issuance of shares	$ 18,200,000
Subsequent Event [Member] | Series C Preferred Stock [Member] | Maryland State Department of Assessments and Taxation [Member]
Increase in authorized number of shares				30,750,000
Reclassification of common stock shares				5,750,000
Subsequent Event [Member] | 8.25% Series A Cumulative Redeemable Preferred Stock [Member]
Preferred stock, redemption price per share		$ 25.00
Common stock shares authorized				110,000,000
Cumulative redeemable preferred stock, shares authorized		3,663,800
Preferred stock redemption amount		$ 91,595,000
Dividend paid date		Sep. 15, 2017
Record date of dividend		Aug. 15, 2017
Subsequent Event [Member] | 8.0% Series B Cumulative Redeemable Preferred Stock [Member]
Cumulative redeemable preferred stock, shares authorized				4,000,000