Summary Of Significant Accounting Policies (Narrative) (Details) $ in Thousands		3 Months Ended	12 Months Ended		36 Months Ended
	Oct. 16, 2017 USD ($)	Jun. 30, 2017 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2012 financial_institution	Jan. 01, 2019 USD ($)	Dec. 31, 2018 USD ($)
Lease term			7 years
Reduction to estimated loss share liability as a result of adjustment related to clawback provisions		$ 4,900		$ 1,658
Net payment to FDIC as consideration for early termination of loss share agreements	$ 15,200
Pre-tax gain on write off	$ 400
Other real estate owned, excluding covered other real estate owned			$ 15,200				$ 24,800
Bank-owned life insurance			187,500				$ 147,900
Operating lease liability						$ 199,400
Operating lease right-of-use asset						170,600
Lease liability			197,639
Right-of-use asset			$ 165,700
ASU 2017-08
Cumulative effect adjustment from the adoption of ASU						1,531
ASU 2016-02
Operating lease liability						199,400
Operating lease right-of-use asset						170,600
Retained earnings | ASU 2017-08
Cumulative effect adjustment from the adoption of ASU						$ 1,531
Minimum
Tax benefit realized on settlement (greater than) (as a percent)			50.00%
Maximum
Intangible assets with finite lives, amortization period			20 years
Furniture, fixtures and equipment | Minimum
Premises and equipment, useful lives			2 years
Furniture, fixtures and equipment | Maximum
Premises and equipment, useful lives			15 years
Software and computer-related equipment | Minimum
Premises and equipment, useful lives			2 years
Software and computer-related equipment | Maximum
Premises and equipment, useful lives			7 years
Buildings and improvements | Minimum
Premises and equipment, useful lives			7 years
Buildings and improvements | Maximum
Premises and equipment, useful lives			39 years
Land improvements
Premises and equipment, useful lives			15 years
FDIC Assisted
Number of financial institutions acquired | financial_institution					9
FDIC loss sharing agreement (as a percent)					80.00%