Consolidated Balance Sheets (Parentheticals) - $ / shares	Dec. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Preferred stock, Series D, shares authorized (in shares)	40,040,000
Preferred stock, Series D, par value (in dollars per share)	$ 0.01
Preferred stock, Series D, liquidation value (in dollars per share)	$ 1,000
Preferred stock, Series D, shares issued (in shares)	767
Preferred stock, Series D, shares outstanding (in shares)	767
Common stock, Class A, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, Class A, shares authorized (in shares)	175,000,000	175,000,000
Common stock, Class A, shares issued (in shares)	113,628,601	92,347,643
Common stock, Class A, shares outstanding (in shares)	113,628,601	92,347,643

Face amount or stated value per share of common stock.

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