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Equity Investments in the Managed Programs and Real Estate - Narratives (Details)		3 Months Ended		6 Months Ended
	Jun. 10, 2021 USD ($) unit	Jun. 30, 2021 USD ($) shares	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($) shares	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)	Apr. 13, 2020 shares
Equity investments
Total equity in earnings (losses) of equity method investments		$ (156,000)	$ 33,983,000	$ (9,889,000)	$ (11,807,000)
Distributions of earnings from equity method investments				3,730,000	3,121,000
Other-than-temporary impairment charges				6,800,000
Equity method investments in real estate		351,865,000		351,865,000		$ 283,446,000
Equity method investments
Equity investments
Investment income		300,000		300,000
Real Estate
Equity investments
Equity method investments in real estate		289,939,000		289,939,000		226,889,000
Real Estate \| Unconsolidated Real Estate Investment
Equity investments
Distributions of earnings from equity method investments				11,100,000	8,500,000
Aggregate unamortized basis difference on equity investments		8,900,000		8,900,000		16,100,000
Managed Programs
Equity investments
Total equity in earnings (losses) of equity method investments		1,698,000	$ 33,772,000	3,084,000	(13,583,000)
Affiliated Entity \| WLT
Equity investments
Total equity in earnings (losses) of equity method investments		(4,000,000.0)		(8,500,000)
Affiliated Entity \| CPA:18 – Global
Equity investments
Distributions of earnings from equity method investments				900,000	1,800,000
Equity method investments in real estate		$ 56,590,000		$ 56,590,000		51,949,000
Affiliated Entity \| CPA:18 – Global \| Class A
Equity investments
Asset management fees receivable, shares \| shares		118,863		118,863
Affiliated Entity \| CPA:18 – Global operating partnership
Equity investments
Distributions of earnings from equity method investments				$ 3,300,000	1,900,000
Equity method investments in real estate		$ 209,000		209,000		209,000
Affiliated Entity \| CWI 1
Equity investments
Distributions of earnings from equity method investments					800,000
Affiliated Entity \| CWI 2
Equity investments
Distributions of earnings from equity method investments					500,000
Affiliated Entity \| CESH
Equity investments
Distributions of earnings from equity method investments				100,000	$ 0
Equity method investments in real estate		5,127,000		5,127,000		4,399,000
Affiliated Entity \| Managed Programs
Equity investments
Aggregate unamortized basis difference on equity investments		21,100,000		21,100,000		18,800,000
Equity method investments in real estate		61,926,000		61,926,000		56,557,000
Affiliated Entity \| Common Stock \| WLT
Equity investments
Shares owned (shares) \| shares							12,208,243
Affiliated Entity \| State Farm Mutual Automobile Insurance Co. \| Real Estate \| CPA:18 – Global
Equity investments
Equity method investments in real estate		7,832,000		7,832,000		15,475,000
Affiliated Entity \| Las Vegas Retail Complex \| Real Estate \| Third Party
Equity investments
Equity method investments in real estate		$ 85,147,000		$ 85,147,000		$ 0
Affiliated Entity \| Las Vegas Retail Complex \| Real Estate \| Third Party \| Construction Commitment
Equity investments
Funding commitment	$ 224,300,000
Stated interest rate (percentage)	6.00%
Debt instrument term (months)	36 months
Equity method investments in real estate	$ 84,900,000
Number of units (units) \| unit	2
Equity purchase option	47.50%
Affiliated Entity \| Las Vegas Retail Complex \| Real Estate \| Third Party \| Construction Commitment \| Minimum
Equity investments
Funding term (months)	15 months
Affiliated Entity \| Las Vegas Retail Complex \| Real Estate \| Third Party \| Construction Commitment \| Maximum
Equity investments
Funding term (months)	22 months