Other Assets Other Assets (Details) - USD ($) $ in Thousands		Dec. 31, 2018	Dec. 31, 2017
Cash Surrender Value of Life Insurance		$ 194,897	$ 193,917
Interest and fees receivable income		88,754	82,935
Low Income Housing Tax Credit - LIHTC		59,507	39,235
Equity Method Investments, Other Asset Investments	[1]	59,062	49,432
Income Taxes Receivable		39,096	98,998
Prepaid Expense		18,006	17,800
Equity Investments Without Readily Determinable Fair Value		14,758	14,856
Equity Investments With Readily Determinable Fair Value		4,891	0
Warrants and Rights Outstanding		4,793	5,161
Other Assets, Miscellaneous		39,132	38,389
Other Assets		522,896	540,723
Community Reinvestment Act Investments [Member]
Equity Investments Without Readily Determinable Fair Value		$ 12,548	$ 8,166

[1] Includes equity investments without readily determinable fair values of $12.5 million and $8.2 million at December 31, 2018 and 2017.