Short-Term Debt - Collateral for Short-Term Debt Facilities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Short-term Debt [Line Items]
Total real estate securities owned	$ 114,308	$ 1,491,986
Other assets	0	16,252
Total Collateral for Short-Term Debt Facilities	319,836	2,698,366
Held-for-sale residential loans
Short-term Debt [Line Items]
Loan pledged as collateral	95,023	201,949
Business purpose residential loans
Short-term Debt [Line Items]
Loan pledged as collateral	110,505	988,179
On balance sheet
Short-term Debt [Line Items]
Available-for-sale securities pledged as collateral	24,670	618,881
Sequoia Choice \| Sequoia securities \| Short Term Borrowing Agreement
Short-term Debt [Line Items]
Trading securities pledged as collateral	63,088	111,341
Freddie Mac SLST \| Sequoia securities \| Short Term Borrowing Agreement
Short-term Debt [Line Items]
Trading securities pledged as collateral	0	381,640
Freddie Mac K-Series \| Sequoia securities \| Short Term Borrowing Agreement
Short-term Debt [Line Items]
Trading securities pledged as collateral	26,550	252,284
CAFL \| Sequoia securities \| Short Term Borrowing Agreement
Short-term Debt [Line Items]
Trading securities pledged as collateral	$ 0	$ 127,840

Other Assets Pledged as Collateral

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- Definition

Short-term Debt Pledged as Collateral

+ References

No definition available.

+ Details

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- Definition

Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

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- Definition

Amount of restricted investment in debt security measured at fair value with change in fair value recognized in net income (trading).

+ References

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- Definition

Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5086-111524

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- Definition

The sum of the fair values, as of the date of each statement of financial position presented, of securities that are restricted as collateral for the payment of related debt obligations, primarily secured borrowings and repurchase agreements, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

+ References

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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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