Receivables from and payables to brokers, dealers and clearing organizations (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Brokers and Dealers [Abstract]
Receivable from Broker-dealers	$ 1,608,273	$ 623,523
Securities Failed-to-Deliver	55,655	45,673
Clearing organizations	41,795	3,180
Securities borrowed interest receivable	24,021	9,319
Receivable from brokers, dealers and clearing organizations	1,729,744	681,695
Payable to Broker-Dealers	286,011	185,838
Securities Failed-to-Receive	68,036	57,580
Clearing organizations	33,732	18,063
Securities loaned interest payable	27,364	9,537
Payables to brokers, dealers and clearing organizations	$ 415,143	$ 271,018

Stock borrow interest receivable

No definition available.

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- Definition

Stock loan interest payable

+ References

No definition available.

+ Details

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- References

No definition available.

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- Definition

Amount payable to other broker-dealer and clearing organization, including, but not limited to, security failed-to-receive, deposit received for security loaned, open transaction, and floor-brokerage payable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher SEC
-Name Rule 15c3-1
-Number 240
-Section 15c3-1

+ Details

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- Definition

Amount receivable from correspondent broker-dealer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=68072869&loc=d3e41242-110953

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 20
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=35710130&loc=d3e41645-110958

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- Definition

Amount payable to correspondent broker-dealer.

+ References

No definition available.

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- Definition

Amount of other payables due to broker-dealers or clearing organizations.

+ References

No definition available.

+ Details

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- Definition

Amount receivable from broker-dealers and clearing organizations, including, but not limited to, securities failed-to-deliver, certain deposits for securities borrowed, open transactions, good faith and margin deposits, commissions and floor brokerage receivables.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 20
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=35710130&loc=d3e41645-110958

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- Definition

Amount of right to receive cash and securities on deposit with clearing organizations. Clearing organizations perform post trade processing and trade comparisons among numerous broker-dealers and act as settlement agents between buying and selling broker-dealers.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 310
-URI http://asc.fasb.org/subtopic&trid=2176284

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- Definition

Amount receivable as the result of a fail-to-deliver. A fail-to-deliver is a securities sale to another broker-dealer that has not been delivered to buying broker-dealer by the close of business on the settlement date.

+ References

No definition available.

+ Details

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- Definition

Amount payable as the result of fail-to-receive. A fail-to-receive is a securities purchase from another broker-dealer not received from the selling broker-dealer by the close of business on the settlement date.

+ References

No definition available.

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