Subsequent Event - Additional Information (Detail) $ in Thousands	Apr. 30, 2024 shares	Apr. 29, 2024 USD ($) shares	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Subsequent Event [Line Items]
Assets			$ 45,343,375	$ 44,011,674
Loans			23,637,649	23,172,484
Deposits			$ 36,913,610	$ 35,792,859
Subsequent Event [Member] | Heartland Financial USA, Inc [Member]
Subsequent Event [Line Items]
Merger agreement announced date		Apr. 29, 2024
Business acquisition, all-stock transaction market value		$ 2,000,000
Business acquisition exchange ratio on common stock		0.55
Assets		$ 19,100,000
Loans		11,600,000
Deposits		$ 15,300,000
Subsequent Event [Member] | BofA Securities, Inc [Member]
Subsequent Event [Line Items]
Business acquisition, shares issuable | shares		2,800,000
Business acquisition, proceeds from shares issuable		$ 201,600
Underwriters option to purchase maximum additional number of shares | shares		420,000
Underwriters option to purchase additional number of shares | shares	420,000
Underwriters Option To Purchase Additional Shares Exercisable Term		30 days