Debt Instrument, Number Of Credit Facilities

No definition available.

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- 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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- 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 fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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- 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

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- Definition

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

Reference 2: 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(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Long-term Debt and Other Borrowings - Credit Agreements - Additional Information (Details) - Revolving Credit Facility [Member]	3 Months Ended
	Dec. 31, 2019 USD ($) facility	Sep. 30, 2019 USD ($)	May 16, 2019 USD ($)	Apr. 21, 2017 USD ($)
Parent Company [Member]
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity				$ 300,000,000
Credit facility, commitment fee percentage	0.125%
Borrowings outstanding	$ 0	$ 0
ABR Loans [Member] \| Parent Company [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.125%
ABR Loans [Member] \| Parent Company [Member] \| Fed Funds Effective Rate Overnight Index Swap Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.50%
ABR Loans [Member] \| Parent Company [Member] \| Eurodollar [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.00%
Eurodollar Loans [Member] \| Parent Company [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.125%
Minimum [Member] \| Parent Company [Member]
Debt Instrument [Line Items]
Credit facility, commitment fee percentage	0.08%
Minimum [Member] \| ABR Loans [Member] \| Parent Company [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.00%
Minimum [Member] \| Eurodollar Loans [Member] \| Parent Company [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.875%
Maximum [Member] \| Parent Company [Member]
Debt Instrument [Line Items]
Credit facility, commitment fee percentage	0.20%
Maximum [Member] \| ABR Loans [Member] \| Parent Company [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.50%
Maximum [Member] \| Eurodollar Loans [Member] \| Parent Company [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.50%
TD Ameritrade Clearing, Inc. [Member]
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity	$ 1,450,000,000
Borrowings outstanding	$ 0	$ 0
Number of credit facilities \| facility	2
TD Ameritrade Clearing, Inc. [Member] \| Revolving Facility, 600 Million Dollars [Member]
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity				$ 600,000,000
Credit facility, commitment fee percentage	0.10%
TD Ameritrade Clearing, Inc. [Member] \| Revolving Facility, 850 Million Dollars [Member]
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity			$ 850,000,000
Credit facility, commitment fee percentage	0.08%
TD Ameritrade Clearing, Inc. [Member] \| TDAC Eurodollar Loans [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.00%
TD Ameritrade Clearing, Inc. [Member] \| Federal Funds Rate Loans [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.00%
TD Ameritrade Clearing, Inc. [Member] \| Minimum [Member] \| Revolving Facility, 600 Million Dollars [Member]
Debt Instrument [Line Items]
Credit facility, commitment fee percentage	0.07%
TD Ameritrade Clearing, Inc. [Member] \| Minimum [Member] \| Revolving Facility, 850 Million Dollars [Member]
Debt Instrument [Line Items]
Credit facility, commitment fee percentage	0.06%
TD Ameritrade Clearing, Inc. [Member] \| Minimum [Member] \| TDAC Eurodollar Loans [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.75%
TD Ameritrade Clearing, Inc. [Member] \| Minimum [Member] \| Federal Funds Rate Loans [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.75%
TD Ameritrade Clearing, Inc. [Member] \| Maximum [Member] \| Revolving Facility, 600 Million Dollars [Member]
Debt Instrument [Line Items]
Credit facility, commitment fee percentage	0.175%
TD Ameritrade Clearing, Inc. [Member] \| Maximum [Member] \| Revolving Facility, 850 Million Dollars [Member]
Debt Instrument [Line Items]
Credit facility, commitment fee percentage	0.125%
TD Ameritrade Clearing, Inc. [Member] \| Maximum [Member] \| TDAC Eurodollar Loans [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.25%
TD Ameritrade Clearing, Inc. [Member] \| Maximum [Member] \| Federal Funds Rate Loans [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.25%