Summary of Significant Accounting Policies - Narrative (Details)					12 Months Ended
	Apr. 01, 2019 USD ($)	Apr. 25, 2017 USD ($) $ / shares	Jun. 07, 2016	Jul. 08, 2014	Dec. 31, 2019 USD ($) payment $ / shares shares	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Nov. 19, 2018 USD ($)	Aug. 18, 2017 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Conversion discount (premium) - Convertible senior notes					$ 3,200,000
Minimum
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives of an assets					27 years 6 months
Maximum
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives of an assets					39 years
Management Agreement | Thetis
Summary Of Significant Accounting Policies [Line Items]
Terms of agreement					15 years
Servicing Agreement | Gregory
Summary Of Significant Accounting Policies [Line Items]
Servicing fees percentage					0.42%
Servicing fee consecutive payments for rate reduction | payment					7
Percentage of fair market value of REO				1.00%
Percentage of purchase price of REO				1.00%
Servicing Agreement | Gregory | Minimum
Summary Of Significant Accounting Policies [Line Items]
Servicing fees percentage					0.65%
Servicing Agreement | Gregory | Maximum
Summary Of Significant Accounting Policies [Line Items]
Servicing fees percentage					1.25%
Amended And Restated Management Agreement | Thetis
Summary Of Significant Accounting Policies [Line Items]
Period of common shares held as base management fee (at least)					3 years
2014 Director Equity Plan
Summary Of Significant Accounting Policies [Line Items]
Number of shares available under for distribution (in shares) | shares					78,000
Vesting period					1 year
Annual retainer, shares	40.00%				50.00%
Annual retainer, cash	60.00%				50.00%
2014 Director Equity Plan | Restricted stock
Summary Of Significant Accounting Policies [Line Items]
Number of shares issued to independent directors (in shares) | shares					2,000
Annual retainer amount	$ 100,000				$ 75,000
2016 Equity Incentive Plan
Summary Of Significant Accounting Policies [Line Items]
Vesting period			3 years
Fraction of award vesting period			0.3333
Percentage of outstanding shares on a fully diluted basis (up to)			5.00%
Convertible Notes Payable
Summary Of Significant Accounting Policies [Line Items]
Aggregate principal		$ 87,500,000
Additional aggregate principal								$ 15,900,000	$ 20,500,000
Interest rate		7.25%
Conversion discount (premium) - Convertible senior notes					$ 1,300,000	$ 900,000
Convertible Notes Payable
Summary Of Significant Accounting Policies [Line Items]
Aggregate principal		$ 87,500,000						$ 108,000,000.0
Interest rate		7.25%			7.25%			7.25%	7.25%
Principal amount of note (in dollars per share) | $ / shares		$ 25.00
Common Stock | Convertible Notes Payable
Summary Of Significant Accounting Policies [Line Items]
Conversion rate					1.6694
Conversion price per share | $ / shares					$ 14.98
Accounting Standards Update 2018-07 [Member]
Summary Of Significant Accounting Policies [Line Items]
Effect on net income						$ 0	$ 0