Debt Instrument, Stated Interest Spread

No definition available.

Name:	gdot_DebtInstrumentStatedInterestSpread
Namespace Prefix:	gdot_
Data Type:	num:percentItemType
Balance Type:	na
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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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

+ Details

Name:	us-gaap_InterestExpenseDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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

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

- Definition

Amount of the required periodic payment applied to principal.

+ References

+ Details

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

- Definition

The cash outflow for a borrowing supported by a written promise to pay an obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

+ Details

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

- 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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- Details

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- Details

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- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_SecuredDebtMember
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- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
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- Details

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Note Payable - Narrative (Details) - USD ($)	1 Months Ended			3 Months Ended		9 Months Ended
Note Payable - Narrative (Details) - USD ($)	Oct. 31, 2019	Mar. 31, 2019	Oct. 31, 2014	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Debt Instrument [Line Items]
Repayments of notes payable						$ 60,000,000	$ 16,875,000
Bank Of America, N.A., Wells Fargo Bank, National Association, And Other Lenders \| Line of credit
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 225,000,000.0
Interest expense				$ 0	$ 600,000	$ 600,000	$ 2,300,000
Bank Of America, N.A., Wells Fargo Bank, National Association, And Other Lenders \| Line of credit \| Federal funds rate
Debt Instrument [Line Items]
Spread on interest rate						0.50%
Bank Of America, N.A., Wells Fargo Bank, National Association, And Other Lenders \| Line of credit \| Base rate
Debt Instrument [Line Items]
Spread on interest rate						1.00%
Bank Of America, N.A., Wells Fargo Bank, National Association, And Other Lenders \| Line of credit \| Minimum \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate						2.50%
Bank Of America, N.A., Wells Fargo Bank, National Association, And Other Lenders \| Line of credit \| Minimum \| Base rate
Debt Instrument [Line Items]
Basis spread on variable rate						1.50%
Bank Of America, N.A., Wells Fargo Bank, National Association, And Other Lenders \| Line of credit \| Maximum \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate						3.00%
Bank Of America, N.A., Wells Fargo Bank, National Association, And Other Lenders \| Line of credit \| Maximum \| Base rate
Debt Instrument [Line Items]
Basis spread on variable rate						2.00%
Bank Of America, N.A., Wells Fargo Bank, National Association, And Other Lenders \| Term facility \| Line of credit
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 150,000,000.0
Debt term			5 years
Quarterly principal payment						$ 5,600,000
Repayments of notes payable		$ 60,000,000.0
Bank Of America, N.A., Wells Fargo Bank, National Association, And Other Lenders \| Revolving facility \| Line of credit
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 75,000,000.0
Debt term			5 years
Subsequent Event \| Revolving facility \| Line of credit
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 100,000,000.0
Debt term	5 years
Subsequent Event \| Wells Fargo Bank \| Line of credit \| Minimum \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.25%
Subsequent Event \| Wells Fargo Bank \| Line of credit \| Minimum \| Base rate
Debt Instrument [Line Items]
Basis spread on variable rate	0.25%
Subsequent Event \| Wells Fargo Bank \| Line of credit \| Maximum \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	2.00%
Subsequent Event \| Wells Fargo Bank \| Line of credit \| Maximum \| Base rate
Debt Instrument [Line Items]
Basis spread on variable rate	1.00%