The price per share of the conversion feature embedded in the debt instrument.

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Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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Debt Instrument, Convertible, Earliest Redemption Period By Company

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Payments To Acquire Securitized Debt

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Financings - Convertible Senior Unsecured Notes (Details)	1 Months Ended		12 Months Ended
	Aug. 31, 2019 USD ($)	Oct. 31, 2017 USD ($) $ / shares	Dec. 31, 2019 USD ($)
Convertible Debt \| Six Point Seventy Five Percent Convertible Senior Unsecured Notes
Debt Instrument [Line Items]
Debt instrument, face amount	$ 40,000,000.0	$ 115,000,000.0	$ 205,000,000.0
Interest rate, stated percentage	6.75%	6.75%	6.75%
Proceeds from issuance of long-term debt	$ 38,800,000	$ 111,100,000
Convertible senior unsecured notes, earliest redemption period by company	3 months	3 months	3 months
Redemption price, percentage		100.00%
Convertible senior unsecured notes, conversion price (in dollars per share) \| $ / shares		$ 12.02
Convertible Debt \| December 2019 Reopened Notes
Debt Instrument [Line Items]
Debt instrument, face amount			$ 50,000,000.0
Interest rate, stated percentage			6.75%
Proceeds from issuance of long-term debt			$ 49,200,000
Convertible Debt \| Three Point Seventy Five Percent Convertible Senior Unsecured Notes
Debt Instrument [Line Items]
Convertible senior unsecured notes, conversion ratio		0.0831947
RETL Trust \| Secured Debt
Debt Instrument [Line Items]
Debt instrument, face amount			674,331,000
RETL Trust \| Secured Debt \| Commercial Mortgage Pass-Through Certificate, Class A
Debt Instrument [Line Items]
Debt instrument, face amount			219,431,000
MRCD Trust \| Secured Debt
Debt Instrument [Line Items]
Debt instrument, face amount			245,000,000
MRCD Trust \| Secured Debt \| Commercial Mortgage Pass-Through Certificate, Class A
Debt Instrument [Line Items]
Payments to acquire securitized debt			150,900,000
Debt instrument, face amount			$ 234,500,000