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Financing Receivable Recorded Investment, Excluding Accrued Interest, Nonaccrual Loans

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Increase (Decrease), In Transit Of Securities (Other Assets)

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Represents the amount of accretion/ amortization of discount, premium and other fees on mortgage loans on real estate accreted/ amortized during the reporting period.

No definition available.

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Mortgage Loans on Real Estate, Financing Receivable, Excluding Accrued Interest, Allowance For Credit Loss, Writeoff

No definition available.

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Number of Loans With Related Write-Off

No definition available.

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Realized Gain On Loans Held For Sale

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Unrealized Lower Of Cost Or Market Adjustment Reversal

No definition available.

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Amount of decrease in investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate, from collection of principal.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 29
-Paragraph Column G
-Footnote 6
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section S50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478322/948-310-S50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-URI https://asc.fasb.org/1943274/2147479628/948-310-S99-1

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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
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The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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-SubTopic 10
-Topic 230
-Publisher FASB
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(13)(h))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1

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Amount of investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column G)(Footnote 3))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479628/948-310-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section S50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478322/948-310-S50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 310
-Name Accounting Standards Codification
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-Subparagraph (SX 210.12-29(Column G))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479628/948-310-S99-1

Name:	us-gaap_MortgageLoansOnRealEstate
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Amount of decrease in investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate, from sale.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section S50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478322/948-310-S50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
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-Name Accounting Standards Codification
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-Subparagraph (SX 210.12-29(Column G)(Footnote 6))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479628/948-310-S99-1

Name:	us-gaap_MortgageLoansOnRealEstateCostOfMortgagesSold
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Name:	us-gaap_MortgageLoansOnRealEstateForeclosures
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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Amount of increase in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate, from new investment.

Name:	us-gaap_MortgageLoansOnRealEstateNewMortgageLoans
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

Name:	us-gaap_MovementInMortgageLoansOnRealEstateRollForward
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Data Type:	xbrli:stringItemType
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Name:	srt_MortgageLoansOnRealEstateLoanTypeAxis=ladr_MortgageLoansHeldByConsolidatedSubsidiariesMember
Namespace Prefix:
Data Type:	na
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Name:	srt_MortgageLoansOnRealEstateLoanTypeAxis=ladr_MortgageLoanReceivablesHeldForInvestmentMember
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Data Type:	na
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Name:	us-gaap_CollateralAxis=ladr_OneOfCompanyLoansMember
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Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=ladr_OfficeLoanMember
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