Acquisitions and Divestitures (Narrative) (Details) $ in Thousands	3 Months Ended	4 Months Ended
	Apr. 03, 2017 USD ($)	May 04, 2017 USD ($) number	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 16, 2016 USD ($)
Business Acquisition [Line Items]
Total assets			$ 29,618,600	$ 28,555,231
Capital Bank Financial Corp [Member]
Business Acquisition [Line Items]
Total assets			$ 10,000,000
Number Of Bank Branches | number		193
Expected cash payment to acquire business, gross		$ 411,000
Estimated Percent Of Common Shares Held By Aquired Entity After Merger		29.00%
Aggregate Transaction Value		$ 2,200,000
Coastal Securities
Business Acquisition [Line Items]
Expected cash payment to acquire business, gross	$ 130,000
As Acquired [Member] | GE Capital Member [Member]
Business Acquisition [Line Items]
Loans acquired					$ 537,400