Fair Value of Financial Assets and Liabilities (Details) - Schedule of convertible note valuation model - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended	12 Months Ended
Aug. 06, 2020	Mar. 31, 2021	Dec. 31, 2020	Jan. 09, 2020
Schedule of convertible note valuation model [Abstract]
Face value (in Dollars)	$ 4,000	$ 4,000	$ 4,000
Coupon rate	12.00%	12.00%	12.00%
Stock price (in Dollars per share)	$ 0.24	$ 0.17	$ 0.19	$ 5.20
Term	1 year		219 days
Risk-free interest rate	0.14%	0.05%	0.09%
Volatility	80.00%	84.00%	70.00%

Amount of face value of notes receivable.

No definition available.

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- Definition

Coupon rate is the rate of interest paid by bond issuers on the bond’s face value.

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No definition available.

+ Details

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Period Type:	duration

- References

No definition available.

+ Details

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- Definition

The estimated measure of the percentage amount by which a share price is expected to fluctuate during the expected term of a non vested share or option award issued to other than an employee.

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No definition available.

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Namespace Prefix:	celu_
Data Type:	dtr:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The risk-free interest rate assumption that is used in valuing a nonvested share or option award issued to other than an employee.

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No definition available.

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- Definition

Period an equity-based award is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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- Definition

Price of a single share of a number of saleable stocks of a company.

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No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant