Statements of Cash Flows Statement	12 Months Ended
	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Operating activities:
Net loss attributable to the Company	$ (7,244,000)	$ 43,467,000	$ 27,681,000
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	(7,458,000)	44,538,000	28,667,000
Reconciliation of net loss to net cash provided by (used in) operating activities:
Depreciation expense	185,065,000	171,136,000	116,777,000
Amortization of above and below Market Leases	(5,765,000)	(5,905,000)	(3,335,000)
Deferred fee income amortization	(5,346,000)	(4,323,000)	(2,347,000)
amortization of purchase option termination fee income	(9,111,000)	(8,660,000)	0
adjustment to net income MBS revenue amortization noncash	(928,000)	(320,000)	0
Deferred Sales Inducement Cost, Amortization Expense	1,997,000	1,644,000	631,000
Deferred loan cost amortization	6,450,000	7,108,000	5,084,000
deferred interest income	(5,766,000)	3,524,000	(4,970,000)
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	(1,831,000)	(320,000)	0
Share-based Compensation	1,223,000	1,703,000	3,470,000
Gain (Loss) on Disposition of Assets	(1,567,000)	(69,705,000)	(37,635,000)
Gain (Loss) on Condemnation	(207,000)	0	0
cash inflows purchase option terminations	3,591,000	7,740,000	0
Gain (Loss) on Extinguishment of Debt	84,000	0	888,000
Gain (Loss) on Sale of Mortgage Loans	(747,000)	0	0
noncash loan interest income	(637,000)	0	0
cash inflows mortgage interest from consolidated VIE	18,750,000	6,049,000	0
mortgage interes cash outflows consolidated VIE	(18,750,000)	(6,049,000)	0
Allowance for Loan and Lease Losses, Period Increase (Decrease)	2,038,000	2,533,000	0
Other Operating Activities, Cash Flow Statement	0	0	189,000
Changes in operating assets and liabilities:
(Increase) in tenant accounts receivable	(20,565,000)	(7,631,000)	(12,105,000)
Payments for (Proceeds from) Tenant Allowance	(644,000)	(7,607,000)	(14,260,000)
Loans and Leases Receivable, Allowance	2,038,000	2,533,000	0
(Increase) decrease in other assets	1,518,000	2,876,000	2,382,000
Increase in accounts payable and accrued expenses	2,406,000	6,730,000	2,853,000
Net cash provided by (used in) operating activities	145,631,000	145,381,000	86,289,000
Investing activities:
Investments in real estate loans	(98,418,000)	(200,806,000)	(148,346,000)
Proceeds from Principal Repayments on Loans and Leases Held-for-investment	54,384,000	250,448,000	94,410,000
Notes receivable issued	3,089,000	12,759,000	6,100,000
Deferred acquisition fee on real estate loans	(40,458,000)	(51,789,000)	(35,281,000)
Deferred real estate loan income	(5,692,000)	(9,946,000)	(7,864,000)
Acquisition of properties, net	(619,089,000)	(1,007,048,000)	(779,643,000)
Proceeds from Sale of Real Estate Held-for-investment	0	164,838,000	116,813,000
Receipt of insurance proceeds for capital improvements	746,000	978,000	4,719,000
Proceeds from Sale of Land Held-for-use	643,000	0	0
Payments to Develop Real Estate Assets	(100,000)	0	0
Additions to real estate assets - improvements	(48,071,000)	(44,383,000)	(11,594,000)
Increase (Decrease) in Earnest Money Deposits Outstanding	(146,000)	4,534,000	(2,034,000)
AcquisitionFeesRelatedPartyCosts	(783,000)	(2,166,000)	(1,320,000)
cash paid investment in CMBS	(30,841,000)	(45,927,000)	0
Proceeds from Sale of Mortgage-backed Securities (MBS), Available-for-sale	79,558,000	0	0
mortgage principal received from consolidated VIE	6,570,000	1,255,000	0
Increase (Decrease) in Accounts and Notes Receivable	35,239,000	41,117,000	34,229,000
Net cash (used in) investing activities	(661,057,000)	(881,805,000)	(727,177,000)
Financing activities:
Proceeds from mortgage notes payable	405,430,000	602,375,000	517,489,000
Extinguishment of Debt, Amount	(176,903,000)	(121,797,000)	(124,040,000)
Payments for mortgage loan costs	(8,705,000)	(12,299,000)	(14,772,000)
Payment for Debt Extinguishment or Debt Prepayment Cost	0	0	(817,000)
loan balance proceeds from real estate loan participants	0	5,000	224,000
payments received from real estate loan participants	(5,223,000)	(10,425,000)	(7,883,000)
Proceeds from non-revolving lines of credit	265,200,000	550,300,000	275,000,000
Payments on revolving lines of credit	(322,200,000)	(535,100,000)	(360,700,000)
Proceeds from Short-term Debt	(70,000,000)
Repayments of Short-term Debt		(11,000,000)	0
mortgage principal paid to consolidated VIE	(6,570,000)	(1,255,000)	0
cash flows financing proceeds repurchase agreements	4,857,000	0	0
cash flows financing repayments repurchase agreements	(4,857,000)	0	0
Proceeds from sales of Units, net of offering costs	501,076,000	408,644,000	306,947,000
Proceeds from Issuance of Common Stock	0	0	74,213,000
Proceeds from Warrant Exercises	11,659,000	20,052,000	80,970,000
Preferred Stock, Redemption Amount	(12,124,000)	(9,367,000)	(4,480,000)
Dividends declared and paid	(45,439,000)	(39,865,000)	(27,409,000)
Payments of Ordinary Dividends, Preferred Stock and Preference Stock	(110,827,000)	(84,427,000)	(61,966,000)
Payments for deferred offering costs, net of non cash items	(4,013,000)	(3,705,000)	(6,314,000)
Net Cash Provided by (Used in) Financing Activities	564,989,000	751,102,000	646,185,000
Cash and Cash Equivalents, Period Increase (Decrease)	49,563,000	14,678,000	5,297,000
Cash beginning of period	87,690,000	73,012,000	67,715,000
Cash end of period	137,253,000	87,690,000	73,012,000
Supplemental cash flow information:
Cash paid for interest	103,298,000	86,222,000	59,851,000
Noncash Investing and Financing Items [Abstract]
Accrued capital expenditures	4,816,000	2,317,000	2,305,000
Deemed noncash dividend	768,000	229,000	63,000
Dividends payable to non controlling interests	225,000	228,000	221,000
Payments of Ordinary Dividends, Noncontrolling Interest	(911,000)	(1,034,000)	(817,000)
Accrued and payable deferred offering costs	3,836,000	461,000	323,000
receivable for deferred offering costs	261,000	480,000	836,000
Writeoff of fully amortized deferred loan costs	1,919,000	4,829,000	411,000
Writeoff of assets due to hurricane damages	0	0	6,879,000
Payments for Tenant Improvements	0	18,202,000	28,803,000
Variable Interest Entity, Consolidated, Assets, Noncurrent, Pledged	270,669,000	264,886,000	0
Variable Interest Entity, Consolidated, Liabilities, Noncurrent	270,670,000	0	0
deconsolidation of VIE assets	578,707,000	0	0
deconsolidation of VIE liabilities	578,707,000	0	0
Proceeds from Sale of Loans Receivable	747,000	0	0
Reclass of offering costs from deferred asset to equity	12,551,000	4,044,000	2,515,000
loan receivables converted to equity for property acquisition	47,797,000	0	0
Contribution from non-controlling interests	(4,539,000)	0	(540,000)
Loans Assumed	41,550,000	47,125,000	90,722,000
Share-based Compensation	719,000	4,972,000	4,088,000
Noncash settlement of loans	512,000	1,890,000	1,512,000
loan fees received	1,565,000	4,331,000	2,634,000
mortgage debt refinanced	65,607,000	152,770,000	162,945,000
Restricted Cash and Cash Equivalents	42,872,000	48,732,000
Proceeds from Delayed Tax Exempt Exchange	0	0	31,288,000
Sales Of Agency Mortgage Backed Security Investments, Settled After Year-End	0	41,181,000	0
Common Stock [Member]
Noncash Investing and Financing Items [Abstract]
Dividends payable	12,156,000	10,840,000	9,576,000
Series A Preferred Stock [Member]
Noncash Investing and Financing Items [Abstract]
Dividends payable	10,020,000	7,920,000	5,971,000
Series M Preferred Stock [Member]
Noncash Investing and Financing Items [Abstract]
Dividends payable	560,000	269,000	70,000
Series A1 Preferred Stock [Domain]
Noncash Investing and Financing Items [Abstract]
Dividends payable	15,000	0	0
Parent [Member]
Operating activities:
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ (7,244,000)	$ 43,467,000	27,681,000
Noncash Investing and Financing Items [Abstract]
Contribution from non-controlling interests			$ 0