Loans and Leases (Details 9) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance, beginning of period	$ 135,037		$ 132,139	$ 132,472
Reserve for Unfunded Loan Commitments, Balance, beginning of period	34,861		35,361	36,861	$ 28,635
Allowance for Credit Losses, Balance, beginning of period	169,898		167,500	169,333
Allowance for Loan and Lease Losses, Charge-offs	(6,501)		(3,308)	(27,603)
Reserve for Unfunded Loan Commitments, Charge-offs	0		0	0	0
Allowance for Credit Losses, Charge-offs	(6,501)		(3,308)	(27,603)
Allowance for Loan and Lease Loss, Recoveries	2,016		1,589	11,683
Reserve for Unfunded Loan Commitments, Recoveries	0		0	0	0
Allowance for Credit Losses, Recoveries	2,016		1,589	11,683
Allowance for Loan and Lease Losses, Net charge-offs	(4,485)		(1,719)	(15,920)
Reserve for Unfunded Loan Commitments, Net charge-offs	0		0	0	0
Allowance For Credit Losses, Net charge-offs	(4,485)		(1,719)	(15,920)
Allowance for Loan and Lease Losses, Provision (negative provision)	8,000		11,500	22,000
Reserve for Unfunded Commitments, Provision (negative provision)	1,000		0	3,000	(6,726)
Allowance for Credit Losses, Provision (negative provision)	7,000	$ 8,000	11,500	19,000	33,000
Balance, end of period	138,552	135,037	141,920	138,552	141,920
Reserve for Unfunded Loan Commitments, Balance, end of period	33,861	34,861	35,361	33,861	35,361
Allowance for Credit Losses, Balance, end of period	172,413	169,898	177,281	172,413	177,281
Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance, beginning of period	135,037		132,139	132,472	139,456
Allowance for Credit Losses, Balance, beginning of period					168,091
Allowance for Loan and Lease Losses, Charge-offs	(6,501)		(3,308)	(27,603)	(33,696)
Allowance for Credit Losses, Charge-offs					(33,696)
Allowance for Loan and Lease Loss, Recoveries	2,016		1,589	11,683	9,886
Allowance for Credit Losses, Recoveries					9,886
Allowance for Loan and Lease Losses, Net charge-offs					(23,810)
Allowance For Credit Losses, Net charge-offs					(23,810)
Allowance for Loan and Lease Losses, Provision (negative provision)	8,000		11,500	22,000	26,274
Allowance for Credit Losses, Provision (negative provision)					33,000
Balance, end of period	$ 138,552	$ 135,037	141,920	$ 138,552	141,920
Allowance for Credit Losses, Balance, end of period			$ 177,281		177,281
Purchased Credit Impaired Loans and Leases
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance, beginning of period					$ 6,400