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Derivatives and Hedging Activities - Gains/(Losses) on Derivative Instruments in Fair Value and Cash Flow Accounting Hedging Relationships (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Interest income/(expense), including the effects of fair value and cash flow hedges | $ 337,118 | $ 232,167 | $ 857,251 | $ 659,070
Interest income/(expense), including the effects of fair value and cash flow hedges | (60,396) | (33,718) | (142,399) | (80,877)
Interest rate contracts | Interest income on loans receivable | Fair value hedging |  |  |  |
Gain/(loss) on fair value hedging relationships: |  |  |  |
Amounts related to interest settlements on derivatives | 13,113 | 4,348 | 27,123 | 11,753
Recognized on derivatives | 3,044 | 13,223 | (6,937) | 3,766
Recognized on hedged items | (1,972) | (13,195) | 7,254 | (3,367)
Net income/(expense) recognized on fair value hedges | 14,185 | 4,376 | 27,440 | 12,152
Interest rate contracts | Interest expense on FHLB advances | Cash flow hedging |  |  |  |
Gain/(loss) on cash flow hedging relationships: |  |  |  |
Amounts related to interest settlements on derivatives | 11,718 | 10,639 | 35,279 | 27,370
Amount of derivative gain/(loss) reclassified from AOCI into interest income/expense | 0 | 0 | 0 | 0
Net income/(expense) recognized on cash flow hedges | $ 11,718 | $ 10,639 | $ 35,279 | $ 27,370

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- Definition The aggregate interest and fee income generated by: (1) loans the Entity has positive intent and ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (a) industrial and agricultural; (b) real estate; and (c) real estate construction loans; (d) trade financing; (e) lease financing; (f) home equity lines-of-credit; (g) automobile and other vehicle loans; and (h) credit card and other revolving-type loans and (2) loans and leases held-for-sale which may include mortgage loans, direct financing, and sales-type leases. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1 + Details
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