Debt And Lines Of Credit , Narrative - Aspen Preferred OP Units and Series B-3 preferred OP units (Details) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended	9 Months Ended
	Jun. 30, 2018 USD ($)	Mar. 31, 2020 USD ($)	Sep. 30, 2019 shares $ / shares Rate	Dec. 31, 2019 USD ($)	Jun. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2014 $ / shares
Debt Instrument [Line Items]
Document Period End Date		Mar. 31, 2020
Convertible units to shares (in shares) | shares			1,013,819
Financial Instruments Subject to Mandatory Redemption, Rate Of Return	6.00%
Financial Instruments Subject to Mandatory Redemption, Term	7 years
Preferred Equity, Mandatorily Redeemable [Member]
Debt Instrument [Line Items]
Financial Instruments Subject to Mandatory Redemption, Value of Shares Issued | $	$ 35,300
Preferred OP units - mandatorily redeemable | $		$ 35,249		$ 35,249	$ 35,200
Preferred OP units [Member]
Debt Instrument [Line Items]
Convertible units to shares (in shares) | shares			270,000
Preferred OP units - mandatorily redeemable | $		$ 34,663		$ 34,663
Preferred OP units [Member] | Convertible debt - Aspen Preferred OP Units January 2024 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount | $						$ 34,700
Convertible units to shares (in shares) | shares			433,072
Debt Instrument, Interest Rate During Period | Rate			3.80%
Debt Instrument, Convertible, Conversion Price | $ / shares			$ 27.00				$ 68.00
Debt Instrument, Convertible, Percent Of Amount By Which The Market Price Of Common Stock Exceeds Threshold | Rate			25.00%
Conversion of Stock, Shares Converted | shares			0.397