Amortization expense of basis difference.

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Capital contribution amount for partnership.

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Represents the percent of economic interest in an equity method investment.

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Number of Variable Interest Entities

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Percentage of call contribution.

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Unfunded loan commitments to borrowers

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Venture equity percentage of ownership.

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Represents the caption on the face of the balance sheet to indicate that the entity has entered into (1) purchase or supply arrangements that will require expending a portion of its resources to meet the terms thereof, and (2) is exposed to potential losses or, less frequently, gains, arising from (a) possible claims against a company's resources due to future performance under contract terms, and (b) possible losses or likely gains from uncertainties that will ultimately be resolved when one or more future events that are deemed likely to occur do occur or fail to occur.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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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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The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

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Net carrying amount of the assets and liabilities in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), when the reporting entity is not the VIE's primary beneficiary.

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INVESTMENTS IN PARTNERSHIPS (Narrative) (Details) $ in Thousands				1 Months Ended	3 Months Ended		9 Months Ended
	Sep. 20, 2019 USD ($)	Apr. 01, 2019 USD ($)	Jun. 01, 2018 USD ($)	Jul. 31, 2019 USD ($)	Sep. 30, 2019 USD ($) entity	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) entity	Sep. 30, 2018 USD ($)	Jun. 30, 2019	Dec. 31, 2018 USD ($) entity
Schedule of Equity Method Investments [Line Items]
Carrying value of equity investments					$ 222,567		$ 222,567			$ 155,079
Unamortized balance					2,190		2,190
Equity in gains (losses) from equity method investments					6,024	$ 3,273	15,643	$ 5,655
Commitments and Contingencies.
Loans and Leases Receivable, Net Amount, Total					87,267		87,267			67,299
U.S. Real Estate Partnerships [Member]
Schedule of Equity Method Investments [Line Items]
Carrying value of equity investments					$ 20,421		$ 20,421			$ 19,961
Number of Variable Interest Entities \| entity					4		4			4
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net					$ 900		$ 900			$ 900
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount					900		900			900
U.S. Real Estate Partnerships formed in Q4 2014[Member]
Schedule of Equity Method Investments [Line Items]
Carrying value of equity investments					$ 19,500		$ 19,500
Equity method investment, ownership percentage					80.00%		80.00%
Equity method investment, economic interest percentage					78.50%		78.50%
U.S. Real Estate Partnerships formed in Q1 2018 [Member]
Schedule of Equity Method Investments [Line Items]
Carrying value of equity investments					$ 900		$ 900
Solar Facilities Investment [Member]
Schedule of Equity Method Investments [Line Items]
Carrying value of equity investments					194,647		194,647			126,339
Cumulative basis adjustment			$ 4,500		3,300		3,300
Amortization expense of basis difference					$ 200		$ 700
Equity method investment, ownership percentage					50.00%		50.00%
Solar Facilities Investment [Member] \| Unfunded Loan Commitment [Member]
Schedule of Equity Method Investments [Line Items]
Unfunded loan commitments to borrowers					$ 446,800		$ 446,800
Solar Construction Lending LLC [Member]
Schedule of Equity Method Investments [Line Items]
Carrying value of equity investments					$ 101,500		$ 101,500
Equity method investment, ownership percentage					50.00%		50.00%
Solar Permanent Lending LLC [Member]
Schedule of Equity Method Investments [Line Items]
Carrying value of equity investments					$ 100		$ 100
Equity method investment, ownership percentage					50.00%		50.00%
Solar Development Lending, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Capital contribution amount for partnership	$ 28,800
Carrying value of equity investments					$ 93,000		$ 93,000
Payments to acquire equity method investments		$ 11,300
Equity method investment, ownership percentage		5.40%			44.70%		44.70%		5.10%
Loans and Leases Receivable, Net Amount, Total		$ 11,300			$ 20,000		$ 20,000
Percentage of call contribution	100.00%
Solar Development Lending, LLC [Member] \| Capital Partner
Schedule of Equity Method Investments [Line Items]
Capital contribution amount for partnership				$ 30,000
Percentage of call contribution				98.00%
Renewable Energy Lending, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Purchase price paid			$ 5,100
Renewable Energy Lending, LLC [Member] \| Consolidated Entity Excluding Variable Interest Entities (VIE) [Member]
Schedule of Equity Method Investments [Line Items]
Venture equity percentage of ownership					100.00%		100.00%
SAWHF
Schedule of Equity Method Investments [Line Items]
Carrying value of equity investments					$ 7,499		$ 7,499			$ 8,779
Equity method investment, ownership percentage					11.85%		11.85%
Minimum [Member] \| U.S. Real Estate Partnerships formed in Q1 2018 [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage					74.25%		74.25%
Maximum [Member] \| U.S. Real Estate Partnerships formed in Q1 2018 [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage					74.92%		74.92%