Line of Credit Facility, Borrowing Base

No definition available.

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- Definition

Line of Credit Facility, Maximum Borrowing Capacity, Increase

+ References

No definition available.

+ Details

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Namespace Prefix:	ondk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Period Type:	duration

- 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.

+ Details

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Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying amount as of the date of the latest financial statement presented of other securities classified as available for sale or held for investment which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee does not have the right by contract or custom to sell or re-pledge them to an unrelated party.

+ References

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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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- Details

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Balance Type:
Period Type:

- Details

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- Details

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- Details

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- Details

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- Details

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Debt (Narrative) (Details) - USD ($)	Mar. 12, 2019	Feb. 08, 2019	Jan. 28, 2019	Dec. 17, 2018	Mar. 31, 2019	Dec. 31, 2018	Dec. 08, 2016
Debt Instrument [Line Items]
Loans held for investment that are pledged as collateral					$ 1,000,000,000	$ 1,000,000,000
Credit Facility Due December 2019 \| Revolving Credit Facility
Debt Instrument [Line Items]
Increase in line of credit				$ 19,700,000
Debt Facility, Sun Trust Facility Agreement, Due January 2021 \| Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit			$ 85,000,000
Debt Facility, Sun Trust Facility Agreement, Due January 2021 \| Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Variable interest spread			3.00%
Debt Facility, Loan Assets of OnDeck, LLC, Due April 2022 \| Revolving Credit Facility
Debt Instrument [Line Items]
Increase in line of credit		$ 50,000,000
Variable interest spread		(0.25%)
Credit Facility Due March 2022 \| Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit	$ 180,000,000
Borrowing base	80.00%
Credit Facility Due March 2022 \| Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Variable interest spread	1.75%
Credit Facility, PORT II Agreement, Due March 2022 \| Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit	$ 180,000,000						$ 125,000,000
Borrowing base	80.00%
Credit Facility, PORT II Agreement, Due March 2022 \| Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Variable interest spread	1.75%