Business Combination - Acquired Identifiable Assets and Liabilities Assumed (Detail) - MB Financial, Inc. $ in Millions	Mar. 22, 2019 USD ($)
Consideration paid
Cash payments	$ 469
Fair value of common stock issued	3,121
Stock-based awards	38
Dividend receivable from MB Financial, Inc.	(20)
Total consideration paid	3,608
Fair value of noncontrolling interest in acquiree	197
Assets
Cash and due from banks	1,679
Federal funds sold	35
Other short-term investments	53
Available-for-sale debt and other securities	832
Held-to-maturity securities	4
Equity securities	51
Loans and leases held for sale	12
Portfolio loans and leases	13,414
Bank premises and equipment	266
Operating lease equipment	394
Intangible assets	219
Servicing rights	263
Other assets	750
Total assets acquired	17,972
Liabilities
Deposits	14,489
Other short-term borrowings	267
Accrued taxes, interest and expenses	276
Other liabilities	194
Long-term debt	727
Total liabilities assumed	15,953
Net identifiable assets acquired	2,019
Goodwill	$ 1,786