Business Combinations (Details) - USD ($) $ in Thousands		Feb. 01, 2021	Jun. 30, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Cash and due from banks			$ 179,505	$ 150,464
Loans and leases, net	[1]		19,280,657	18,735,196
Premises and equipment, net			39,541	39,234
Goodwill			1,204,118	1,078,670
Finite Lived Core Deposits Customer Relations Net			18,423	23,641
Other assets			924,497	860,326
Assets			34,867,987	29,498,442
Noninterest-bearing deposits			11,252,286	9,193,827
Borrowings			6,625	5,000
Accrued interest payable and other liabilities			505,859	491,962
Liabilities			$ 31,021,306	$ 25,903,491
Civic
Business Acquisition [Line Items]
Cash and due from banks		$ 37,331
Loans and leases, net		67,294
Premises and equipment, net		1,197
Goodwill		125,448
Finite Lived Core Deposits Customer Relations Net		750
Other assets		75,977
Assets		307,997
Noninterest-bearing deposits		37,339
Borrowings		50,210
Accrued interest payable and other liabilities		60,028
Liabilities		147,577
Business Combination, Consideration Transferred		$ 160,420

[1] Excludes accrued interest receivable of $73.5 million and $79.7 million at June 30, 2021 and December 31, 2020, respectively, which is recorded in "Other assets" on the condensed consolidated balance sheets.