Supporting Financial Information - Changes in Carrying Amount of Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Dec. 31, 2020	Jun. 30, 2021	Sep. 30, 2020
Goodwill [Roll Forward]
Beginning Balance	$ 67,144	$ 65,450	$ 52,758
Preliminary increase from IBA acquisition			14,386
Adjustment from IBA acquisition	(1,694)	193
Ending Balance	$ 65,450	$ 65,643	$ 67,144

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10)(1))
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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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-Publisher FASB
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- Definition

Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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