Loans and Leases (Details 7 - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period			$ 115,111
Balance, end of period	$ 147,976		147,976
The ending balance of the loan and lease portfolio is composed of loans and leases:
Ending balance of loans and leases	14,742,846		14,742,846		$ 14,478,254
Non Purchased Credit Impaired Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	132,000	$ 85,047	105,534	$ 70,456
Charge-offs	(9,924)	(4,312)	(17,009)	(14,846)
Recoveries	6,050	1,081	8,811	5,602
Provision	8,621	10,500	39,411	31,104
Balance, end of period	136,747	92,316	136,747	92,316
Amount of the allowance applicable to loans and leases:
Individually evaluated for impairment	31,120	11,975	31,120	11,975
Collectively evaluated for impairment	105,627	80,341	105,627	80,341
The ending balance of the loan and lease portfolio is composed of loans and leases:
Individually evaluated for impairment	240,772	146,068	240,772	146,068
Collectively evaluated for impairment	14,381,875	12,112,848	14,381,875	12,112,848
Ending balance of loans and leases	14,622,647	12,258,916	14,622,647	12,258,916	14,289,209
Purchased Credit Impaired Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period			9,577
Balance, beginning of period	11,289	14,328	9,577	13,999
Charge-offs	531	(1,119)	(862)	(1,698)
Recoveries	0	0	0	112
Provision	471	(2,254)	2,514	(1,458)
Balance, end of period	11,229		11,229
Balance, end of period	11,229	10,955	11,229	10,955
Amount of the allowance applicable to loans and leases:
Acquired loans with deteriorated credit quality	11,229	10,955	11,229	10,955
The ending balance of the loan and lease portfolio is composed of loans and leases:
Acquired loans with deteriorated credit quality	120,199	193,289	120,199	193,289
Ending balance of loans and leases	120,199	193,289	120,199	193,289	189,045
NonPCI and PCI Loans
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	143,289	99,375	115,111	84,455
Charge-offs	(10,455)	(5,431)	(17,871)	(16,544)
Recoveries	6,050	1,081	8,811	5,714
Provision	9,092	8,246	41,925	29,646
Balance, end of period	147,976	103,271	147,976	103,271
The ending balance of the loan and lease portfolio is composed of loans and leases:
Total loans and leases	14,742,846	12,452,205	14,742,846	12,452,205
Real Estate Mortgage | Non Purchased Credit Impaired Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	29,331	29,908	36,654	25,097
Charge-offs	(302)	(252)	(1,905)	(1,767)
Recoveries	2,414	288	4,352	1,783
Provision	5,498	4,355	(2,160)	9,186
Balance, end of period	36,941	34,299	36,941	34,299
Amount of the allowance applicable to loans and leases:
Individually evaluated for impairment	7,299	1,443	7,299	1,443
Collectively evaluated for impairment	29,642	32,856	29,642	32,856
The ending balance of the loan and lease portfolio is composed of loans and leases:
Individually evaluated for impairment	139,059	58,393	139,059	58,393
Collectively evaluated for impairment	5,325,882	5,446,694	5,325,882	5,446,694
Ending balance of loans and leases	5,464,941	5,505,087	5,464,941	5,505,087	5,688,063
Real Estate Construction and Land | Non Purchased Credit Impaired Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	7,853	3,908	7,137	4,248
Charge-offs	0	0	0	0
Recoveries	27	390	185	1,034
Provision	803	93	1,361	(891)
Balance, end of period	8,683	4,391	8,683	4,391
Amount of the allowance applicable to loans and leases:
Individually evaluated for impairment	11	31	11	31
Collectively evaluated for impairment	8,672	4,360	8,672	4,360
The ending balance of the loan and lease portfolio is composed of loans and leases:
Individually evaluated for impairment	8,700	8,047	8,700	8,047
Collectively evaluated for impairment	822,815	364,433	822,815	364,433
Ending balance of loans and leases	831,515	372,480	831,515	372,480	527,720
Commercial | Non Purchased Credit Impaired Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	93,404	50,531	61,082	39,858
Charge-offs	(9,606)	(4,035)	(14,306)	(12,964)
Recoveries	3,553	239	4,179	2,393
Provision	2,240	6,137	38,636	23,585
Balance, end of period	89,591	52,872	89,591	52,872
Amount of the allowance applicable to loans and leases:
Individually evaluated for impairment	23,631	10,343	23,631	10,343
Collectively evaluated for impairment	65,960	42,529	65,960	42,529
The ending balance of the loan and lease portfolio is composed of loans and leases:
Individually evaluated for impairment	92,637	76,088	92,637	76,088
Collectively evaluated for impairment	7,977,050	6,175,440	7,977,050	6,175,440
Ending balance of loans and leases	8,069,687	6,251,528	8,069,687	6,251,528	7,952,577
Consumer | Non Purchased Credit Impaired Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	1,412	700	661	1,253
Charge-offs	(16)	(25)	(798)	(115)
Recoveries	56	164	95	392
Provision	80	(85)	1,574	(776)
Balance, end of period	1,532	754	1,532	754
Amount of the allowance applicable to loans and leases:
Individually evaluated for impairment	179	158	179	158
Collectively evaluated for impairment	1,353	596	1,353	596
The ending balance of the loan and lease portfolio is composed of loans and leases:
Individually evaluated for impairment	376	3,540	376	3,540
Collectively evaluated for impairment	256,128	126,281	256,128	126,281
Ending balance of loans and leases	$ 256,504	$ 129,821	$ 256,504	$ 129,821	$ 120,849