Interest expense from contingent beneficial conversion feature.

No definition available.

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Namespace Prefix:	owlt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Minimum amount of equity financing excluding conversion value of notes.

+ References

No definition available.

+ Details

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Namespace Prefix:	owlt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage of convertible preferred stock price per share to qualify for equity financing.

+ References

No definition available.

+ Details

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of a written promise to pay a note, initially due after one year or beyond the operating cycle if longer, which can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder.

+ References

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-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

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+ Details

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Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Period Type:	instant

- Definition

Amount of interest expense classified as other.

+ References

No definition available.

+ Details

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

- Definition

The amount for notes payable (written promise to pay), due to related parties.

+ References

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+ Details

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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.

+ Details

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

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Related Party Transactions, Convertible Promissory Notes (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended		12 Months Ended
	Jul. 15, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Related Party Transaction [Line Items]
Conversion price		$ 3.1546		$ 3.1546
Convertible notes payable	$ 2
Interest expense from contingent beneficial conversion feature		$ 26,061	$ 0	$ 26,061	$ 0
Related Party Convertible Promissory [Member]
Related Party Transaction [Line Items]
Notes payable, Related parties						$ 6,500
Interest rate		5.00%		5.00%
Accrued interest on convertible promissory notes	621					447
Unamortized debt issuance cost	$ 3					$ 13
Percentage of convertible preferred stock price per share to qualify for equity financing				80.00%
Minimum amount of equity financing excluding conversion value of notes				$ 15,000
Interest expense from contingent beneficial conversion feature		$ 26,061		$ 26,061