Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Assets
Cash and due from banks	$ 327,440	$ 336,150
Overnight investments	797,406	1,387,927
Investment in marketable equity securities (cost of $73,809 at December 31, 2018)	92,599	0
Investment securities available for sale	4,557,110	7,180,180
Investment securities held to maturity	2,184,653	76
Loans held for sale	45,505	51,179
Loans and Leases	25,523,276	23,596,825
Less allowance for loan and lease losses	(223,712)	(221,893)
Net Loans and Leases	25,299,564	23,374,932
Premises and equipment	1,204,179	1,138,431
Other Real Estate	48,030	51,097
Income earned not collected	109,903	95,249
Goodwill recorded for Palmetto Heritage	236,347	150,601
Intangible Assets, Net (Excluding Goodwill)	72,298	73,096
Other assets	433,595	688,594
Total assets	35,408,629	34,527,512
Deposits [Abstract]
Noninterest-bearing	11,882,670	11,237,375
Interest-bearing	18,789,790	18,028,900
Total deposits	30,672,460	29,266,275
Debt, Current	572,287	693,807
Long-term obligations	319,867	870,240
FDIC shared-loss payable	105,618	101,342
Other liabilities	249,443	261,784
Total liabilities	31,919,675	31,193,448
Shareholders' Equity
Preferred stock - $0.01 par value (10,000,000 shares authorized; no shares issued and outstanding at December 31, 2018 and December 31, 2017)	0	0
Surplus	493,962	658,918
Retained earnings	3,218,551	2,785,430
Accumulated other comprehensive loss	(235,187)	(122,294)
Total shareholders' equity	3,488,954	3,334,064
Total liabilities and shareholders' equity	35,408,629	34,527,512
Class A Common Stock
Shareholders' Equity
Common stock	10,623	11,005
Class B Common Stock
Shareholders' Equity
Common stock	$ 1,005	$ 1,005