Loans and Leases (Details 8) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2017	Jun. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of period				$ 157,238
Reserve for Unfunded Loan Commitments, Balance, beginning of period	$ 20,263		$ 17,944	17,523	$ 16,734
Allowance for Credit Losses, Balance, beginning of period	166,221		161,233	174,761	131,845
Reserve for Unfunded Loan Commitments, Charge-offs	0		0	0	0
Allowance for Credit Losses, Charge-offs	(6,007)		(10,455)	(55,575)	(17,871)
Reserve for Unfunded Loan Commitments, Recoveries	0		0	0	0
Allowance for Credit Losses, Recoveries	5,082		6,050	9,883	8,811
Reserve for Unfunded Loan Commitments, Net charge-offs	0		0	0	0
Allowance For Credit Losses, Net charge-offs	(925)		(4,405)	(45,692)	(9,060)
Reserve for Unfunded Commitments, Provision (negative provision)	(546)		(621)	(3,286)	(589)
Allowance for Credit Losses, Provision (negative provision)	15,119	$ 11,499	8,471	51,346	42,514
Balance, end of period	159,606			159,606
Reserve for Unfunded Loan Commitments, Balance, end of period	20,809	20,263	17,323	20,809	17,323
Allowance for Credit Losses, Balance, end of period	180,415	166,221	165,299	180,415	165,299
Non Purchased Credit Impaired Loans and Leases
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of period	138,879		132,000	143,755	105,534
Allowance for Credit Losses, Balance, beginning of period	159,142		149,944	161,278	122,268
Allowance for Loan and Lease Losses, Charge-offs	5,928		9,924	49,807	17,009
Allowance for Credit Losses, Charge-offs	(5,928)		(9,924)	(49,807)	(17,009)
Allowance for Loan and Lease Loss, Recoveries	4,865		6,050	9,608	8,811
Allowance for Credit Losses, Recoveries	4,865		6,050	9,608	8,811
Allowance for Loan and Lease Losses, Net charge-offs	(1,063)		(3,874)	(40,199)	(8,198)
Allowance For Credit Losses, Net charge-offs	(1,063)		(3,874)	(40,199)	(8,198)
Allowance for Loan and Lease Losses, Provision (negative provision)	14,954		8,621	49,214	39,411
Allowance for Credit Losses, Provision (negative provision)	15,500		8,000	52,500	40,000
Balance, end of period	152,770	138,879	136,747	152,770	136,747
Allowance for Credit Losses, Balance, end of period	173,579	159,142	154,070	173,579	154,070
Purchased Credit Impaired Loans and Leases
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of period				13,483
Balance, beginning of period	7,079		11,289	13,483	9,577
Allowance for Loan and Lease Losses, Charge-offs	79		531	5,768	862
Allowance for Loan and Lease Loss, Recoveries	217		0	275	0
Allowance for Loan and Lease Losses, Net charge-offs	138		(531)	(5,493)	(862)
Allowance for Loan and Lease Losses, Provision (negative provision)	(381)		471	(1,154)	2,514
Balance, end of period	6,836			6,836
Balance, end of period	$ 6,836	$ 7,079	$ 11,229	$ 6,836	$ 11,229