Mergers and Acquisitions - Summary of Purchase Price Allocation (Details) - USD ($) $ in Thousands	Jan. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Oct. 30, 2020	Dec. 16, 2019
Liabilities:
Goodwill		$ 2,514,104	$ 538,373	$ 538,373
ROU lease assets		$ 191,068	$ 119,926
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Property and equipment, net	Property and equipment, net	Property and equipment, net
Operating lease liabilities		$ 239,281	$ 144,804
Operating lease liabilities, location	Accrued expenses and other liabilities	Accrued expenses and other liabilities	Accrued expenses and other liabilities
Sterling
Business Acquisition [Line Items]
Total consideration	$ 5,180,300
Assets:
Cash and due from banks	510,929
Interest-bearing deposits	3,207
Investment securities available-for-sale	4,429,948
Federal Home Loan Bank and Federal Reserve Bank Stock	150,502
Loans held for sale	23,517
Unpaid principal balance, total loans and leases		$ 20,816,348
Total loans and leases	20,498,706
Deferred tax assets, net	(51,487)
Premises and equipment	264,421
Other intangible assets	210,100
Bank-owned life insurance policies	645,510
Accrued interest receivable and other assets	960,893
Total assets acquired	27,646,246
Liabilities:
Non-interest-bearing deposits	6,620,248
Interest-bearing deposits	16,643,755
Securities sold under agreements to repurchase and other borrowings	27,184
Long-term debt	516,881
Accrued expenses and other liabilities	597,643
Total liabilities assumed	24,405,711
Net assets acquired	3,240,535				$ 225,000	$ 274,000
Goodwill	1,939,765
ROU lease assets	100,000
Operating lease liabilities	106,900
Sterling | Commercial non-mortgage
Assets:
Unpaid principal balance, total loans and leases		5,570,782
Total loans and leases	5,527,657
Sterling | Asset-based
Assets:
Unpaid principal balance, total loans and leases		694,137
Total loans and leases	683,958
Sterling | Commercial real estate
Assets:
Unpaid principal balance, total loans and leases		6,790,600
Total loans and leases	6,656,405
Sterling | Multi-family
Assets:
Unpaid principal balance, total loans and leases		4,303,381
Total loans and leases	4,255,906
Sterling | Equipment financing
Assets:
Unpaid principal balance, total loans and leases		1,350,579
Total loans and leases	1,314,311
Sterling | Warehouse lending
Assets:
Unpaid principal balance, total loans and leases		647,767
Total loans and leases	643,754
Sterling | Residential
Assets:
Unpaid principal balance, total loans and leases		1,313,785
Total loans and leases	1,281,637
Sterling | Home equity
Assets:
Unpaid principal balance, total loans and leases		132,758
Total loans and leases	122,553
Sterling | Other consumer
Assets:
Unpaid principal balance, total loans and leases		$ 12,559
Total loans and leases	$ 12,525