REAL ESTATE OWNED - Amortization of intangible assets (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Intangible assets, net
Balance as of December 31, 2019	$ 81,458
2020	44,241
2021	3,341
2022	3,210
2023	3,029
2024	2,883
Thereafter	24,754
Accumulated depreciation	4,131,330	$ 3,654,160
Real estate
Intangible assets, net
Balance as of December 31, 2019	37,844
2020	3,062
2021	2,840
2022	2,740
2023	2,643
2024	2,525
Thereafter	24,034
Accumulated depreciation	2,700
Amortization expense	2,700
In-place lease
Intangible assets, net
Balance as of December 31, 2019	43,614
2020	41,179
2021	501
2022	470
2023	386
2024	358
Thereafter	720
Accumulated depreciation	23,600
Amortization expense	$ 20,800

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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The cumulative amount of depreciation for real estate property held for investment purposes.

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