Other Assets (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Dec. 31, 2019
Other Investment Not Readily Marketable [Line Items]
Cash surrender value of BOLI	$ 200,733	$ 199,029
LIHTC investments	192,963	75,149
Operating lease ROU assets, net (2)	125,325	129,301
Interest receivable	76,150	81,479
CRA investments	74,644	65,152
Prepaid expenses	24,971	17,099
Equity investments without readily determinable fair values	14,967	14,890
Equity warrants	4,781	3,434
Equity investments with readily determinable fair values	2,688	2,998
Taxes receivable	0	31,591
Other receivables/assets	17,235	16,689
Total other assets	734,457	636,811
Increase of investment in low income housing project partnerships	101,000
Community Reinvestment Act Investments
Other Investment Not Readily Marketable [Line Items]
Equity investments without readily determinable fair values	$ 21,000	$ 17,800