Cash Flows Between Transferor and Transferee, Proceeds from New Transfers, Amount Funded

No definition available.

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- Definition

Loan Collateral, Measurement Input

+ References

No definition available.

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- Definition

Mortgage Loans on Real Estate, Commercial and Consumer, Percentage of Portfolio

+ References

No definition available.

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- Definition

Mortgage Loans on Real Estate, Impairment

+ References

No definition available.

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- Definition

Proceeds From Pre-payment Penalties

+ References

No definition available.

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- Definition

Provision For Loan And Lease Losses And Impairment

+ References

No definition available.

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- Definition

Qualitative and Quantitative Information, Transferor's Continuing Involvement, Arrangements of Financial Support, Amount Funded

+ References

No definition available.

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- Definition

Cash Flows between a transferor and a transferee attributable to newly transferred assets related to either a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (d)(1)
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- Definition

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.

+ References

No definition available.

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

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- Definition

The percentage points (also referred to as 'margin') added to the reference rate as stated in the loan agreement and used to compute the variable rate on the loans receivable. For instance, the loan agreement might state that the interest rate the borrower is obligated to pay is the London Interbank Offered Rate (LIBOR) plus three quarters (3/4) of a percentage point adjusted quarterly (each three months). LIBOR in this example is the index or reference rate, 3/4 percentage point is the margin, the reference rate plus the margin is the fully indexed rate. This element would be used to report separately the margin.

+ References

No definition available.

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- Definition

The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
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- Definition

Interest paid other than in cash for example by issuing additional debt securities. As a noncash item, it is added to net income when calculating cash provided by or used in operations using the indirect method.

+ References

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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

The transferor's maximum amount of exposure to loss as a result of its continuing involvement in transferred financial assets.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
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Commercial Mortgage and Subordinate Loans, Net - Additional Information (Details) $ in Thousands	3 Months Ended				9 Months Ended		12 Months Ended		15 Months Ended
	Sep. 30, 2018 USD ($) $ / ft²	Jun. 30, 2018 USD ($) loan	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) $ / ft²	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018
Financing Receivable, Allowance for Credit Losses [Line Items]
Percentage of loan portfolio					100.00%		100.00%
Provision for loan losses and impairment	$ 0		$ 0		$ 5,000	$ 5,000
Carrying value	4,828,046				4,828,046		$ 3,679,758
Payment in kind interest	10,200		5,300		29,900	19,300
Proceeds from pre-payment penalties or accelerated fees	200		$ 3,600		1,800	$ 4,000
Commercial Mortgage and Subordinated Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for loan losses and impairment					5,000
Commercial Mortgage Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for loan losses and impairment					17,000		17,000
Carrying value	3,723,550				3,723,550		2,653,826
Subordinate Mortgage Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for loan losses and impairment					5,000		5,000
Carrying value	1,104,496				1,104,496		$ 1,025,932
Residential Condominium - Bethesda, MD [Member] \| Commercial Mortgage and Subordinated Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan loss provision and impairment									$ 10,000
Provision for loan losses and impairment		$ 5,000		$ 2,000
Multifamily - Williston, ND [Member] \| Commercial Mortgage Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for loan losses and impairment								$ 10,000
Multifamily - Williston, ND [Member] \| Subordinate Mortgage Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for loan losses and impairment								$ 5,000
Office Campus - Renton, WA [Member] \| Subordinate Mortgage Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Proceeds from sale of loan	75,000
Proceeds from sale of loan, amount funded	17,700
Carrying value	265,000				265,000
Exposure to mortgage loan	190,000				190,000
Exposure to mortgage loan, amount funded	$ 65,500				65,500
Other Assets [Member] \| Commercial Mortgage and Subordinated Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Impairment				$ 3,000	$ 3,000
Floating Rate Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Percentage of loan portfolio					90.00%		88.00%
Dollars per square foot [Member] \| Residential Condominium - Bethesda, MD [Member] \| Commercial Mortgage Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan collateral, measurement input \| $ / ft²	662				662
Discount rate [Member] \| Commercial Mortgage Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan collateral, measurement input								0.10
Discount rate [Member] \| Residential Condominium - Bethesda, MD [Member] \| Commercial Mortgage Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan collateral, measurement input	0.15				0.15
Terminal capitalization rate [Member] \| Commercial Mortgage Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan collateral, measurement input								0.11
Contractual Interest Rate Reduction [Member] \| Commercial Mortgage Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Number of loans restructured \| loan		1
Unpaid principal balance of loan restructured		$ 169,000							$ 169,000
Contractual Interest Rate Reduction [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Commercial Mortgage Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Basis spread on variable rate		3.00%							3.00%	5.50%