Long-Term Debt (Details) - USD ($) $ in Millions	6 Months Ended
Jul. 31, 2025	Jan. 31, 2025
Long-Term Debt
Letters of credit outstanding	$ 0.2	$ 0.2
Revolving credit facility \| Senior secured credit facility
Long-Term Debt
Maturity term (year)	5 years
Long-term line of credit drawn amount	$ 0.0
Available for use	350.0
Revolving credit facility \| Senior secured credit facility \| Maximum
Long-Term Debt
Line of credit facility	500.0
Revolving credit facility \| Senior secured credit facility \| Minimum
Long-Term Debt
Line of credit facility	$ 350.0
Senior secured credit facility \| Maximum
Long-Term Debt
Interest rates under the revolving operating portion	2.50%
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration]	dsgx:CanadaOrUsPrimeRateCorraOrSofrMember
Percentage of undrawn amounts (in percentage)	0.40%
Senior secured credit facility \| Minimum
Long-Term Debt
Interest rates under the revolving operating portion	0.00%
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration]	dsgx:CanadaOrUsPrimeRateCorraOrSofrMember
Percentage of undrawn amounts (in percentage)	0.20%

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

No definition available.

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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.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Indicates type of variable interest rate on debt instrument.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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+ Details

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Balance Type:	credit
Period Type:	instant

- 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

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Details

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