Other Non-Interest Expense - Other Non-Interest Expense (Details) - USD ($)		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Other Income and Expenses [Abstract]
Consumer Financial Protection Bureau and OCC settlement charge	[1]	$ 32,000,000	$ 0	$ 0
Advertising and marketing		28,120,000	26,927,000	22,264,000
Professional fees		21,529,000	33,070,000	19,335,000
Outside processing		20,574,000	20,473,000	15,313,000
Card processing and issuance costs		17,461,000	18,325,000	15,856,000
FDIC insurance		15,056,000	16,049,000	15,912,000
Loan and lease processing		13,649,000	22,149,000	26,193,000
Severance		6,324,000	22,299,000	5,280,000
Goodwill impairment		0	73,041,000	0
Other		105,933,000	114,523,000	110,244,000
Total other non-interest expense		$ 260,646,000	$ 346,856,000	$ 230,397,000

[1] See Note 26. Litigation Contingencies for further information.