Loans and Leases (Details 9) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance, beginning of period	$ 136,281	$ 132,472	$ 134,275	$ 132,472
Reserve for Unfunded Loan Commitments, Balance, beginning of period	36,861	36,861	32,861	36,861	$ 28,635
Allowance for Credit Losses, Balance, beginning of period	173,142	169,333	167,136	169,333
Allowance for Loan and Lease Losses, Charge-offs	(17,637)		(18,235)	(21,102)
Reserve for Unfunded Loan Commitments, Charge-offs	0		0	0	0
Allowance for Credit Losses, Charge-offs	(17,637)		(18,235)	(21,102)
Allowance for Loan and Lease Loss, Recoveries	6,393		1,099	9,667
Reserve for Unfunded Loan Commitments, Recoveries	0		0	0	0
Allowance for Credit Losses, Recoveries	6,393		1,099	9,667
Allowance for Loan and Lease Losses, Net charge-offs	(11,244)		(17,136)	(11,435)
Reserve for Unfunded Loan Commitments, Net charge-offs	0		0	0	0
Allowance For Credit Losses, Net charge-offs	(11,244)		(17,136)	(11,435)
Allowance for Loan and Lease Losses, Provision (negative provision)	10,000		15,000	14,000
Reserve for Unfunded Commitments, Provision (negative provision)	2,000		(2,500)	2,000	(6,726)
Allowance for Credit Losses, Provision (negative provision)	8,000	4,000	17,500	12,000	21,500
Balance, end of period	135,037	136,281	132,139	135,037	132,139
Reserve for Unfunded Loan Commitments, Balance, end of period	34,861	36,861	35,361	34,861	35,361
Allowance for Credit Losses, Balance, end of period	169,898	173,142	167,500	169,898	167,500
Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance, beginning of period	136,281	132,472	134,275	132,472	139,456
Allowance for Credit Losses, Balance, beginning of period					168,091
Allowance for Loan and Lease Losses, Charge-offs	(17,637)		(18,235)	(21,102)	(30,388)
Allowance for Credit Losses, Charge-offs					(30,388)
Allowance for Loan and Lease Loss, Recoveries	6,393		1,099	9,667	8,297
Allowance for Credit Losses, Recoveries					8,297
Allowance for Loan and Lease Losses, Net charge-offs					(22,091)
Allowance For Credit Losses, Net charge-offs					(22,091)
Allowance for Loan and Lease Losses, Provision (negative provision)	10,000		15,000	14,000	14,774
Allowance for Credit Losses, Provision (negative provision)					21,500
Balance, end of period	$ 135,037	$ 136,281	132,139	$ 135,037	132,139
Allowance for Credit Losses, Balance, end of period			$ 167,500		167,500
Purchased Credit Impaired Loans and Leases
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance, beginning of period					$ 6,400