Goodwill and Core Deposits and Other Intangibles - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Core deposit and other intangible amortization	$ 2,140	$ 2,477	$ 7,208
Amortization expense for year 2023	8,400
Amortization expense for year 2024	8,000
Amortization expense for year 2025	7,800
Amortization expense for year 2026	6,600
Amortization expense for year 2027	4,200
Carrying amount of Company's goodwill	$ 1,398,253		$ 1,398,253	$ 1,398,253

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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