Nature of operations line items.

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Percentage of interest issued to affliated of purchaser.

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Percentage of ownership interest sold owned In joint venture.

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Shares repurchase cancel and exchanged, shares.

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Value of the difference between preference in liquidation and the par or stated values of the preferred shares.

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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Represents the initial fair value recorded for assets received on transfer of financial assets in a securitization, asset-backed financing arrangement, or a similar transfer which transaction is recognized as a sale of the transferred financial assets.

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The Company - Additional Information (Detail) - USD ($) $ in Thousands						6 Months Ended
	Jun. 27, 2018	Jun. 26, 2018	Mar. 19, 2018	Jun. 22, 2017	Dec. 07, 2016	Jun. 30, 2018
Preferred Series D
Nature Of Operations [Line Items]
Proceeds from sale of investment	$ 56,765		$ 4,863	$ 10,057	$ 11,600
Liquidation preference		$ 73,480
Variable Interest Entity, Not Primary Beneficiary \| RAIT FL5 & FL6 \| Preferred Series D
Nature Of Operations [Line Items]
Shares repurchased and cancelled, shares	2,939,190					2,939,190
Proceeds from sale of investment	$ 56,765					$ 56,765
Variable Interest Entity, Not Primary Beneficiary \| RAIT FL5 & FL6 \| Preferred Series A, B, and C
Nature Of Operations [Line Items]
Liquidation preference	16,715					$ 16,715
Variable Interest Entity, Not Primary Beneficiary \| RAIT FL5 \| Melody 2016 Holdings, LLC
Nature Of Operations [Line Items]
Sale of Interest owned in joint venture		60.00%
Percentage of interest issued to affliated of purchaser		40.00%
Variable Interest Entity, Not Primary Beneficiary \| RAIT FL6 \| Melody 2017 Holdings, LLC
Nature Of Operations [Line Items]
Sale of Interest owned in joint venture		60.00%
Percentage of interest issued to affliated of purchaser		40.00%
Variable Interest Entity, Not Primary Beneficiary \| RAIT IV \| RAIT FL5 & FL6
Nature Of Operations [Line Items]
Aggregate purchase price	$ 54,632