Loans and Leases (Details 7) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Allowance for Loan and Lease Losses [Roll Forward]
Loans and Leases Receivable, Allowance, beginning balance	$ 115,111
Loans and Leases Receivable, Allowance, ending balance	157,238	$ 115,111
Loans held for investment, net	15,455,954	14,478,254
Non Purchased Credit Impaired Loans and Leases [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Loans and Leases Receivable, Allowance, beginning balance	105,534	70,456
Allowance for Loan and Lease Losses, Write-offs	(35,092)	(15,999)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	13,102	8,473
Provision for Loan and Lease Losses	60,211	42,604
Loans and Leases Receivable, Allowance, ending balance	143,755	105,534
Financing Receivable, Individually Evaluated for Impairment	24,933	19,263
Financing Receivable, Collectively Evaluated for Impairment	118,822	86,271
Financing Receivable, Individually Evaluated for Impairment	234,430	168,299
Financing Receivable, Collectively Evaluated for Impairment	15,113,100	14,120,910
Loans held for investment, net	15,347,530	14,289,209
Purchased Credit Impaired Loans and Leases [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Loans and Leases Receivable, Allowance, beginning balance	9,577
Loans and Leases Receivable, Allowance, Covered, beginning balance	9,577	13,999
Allowance for Loan and Lease Losses, Write-offs	(862)	(1,772)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	39	150
Provision for Loan and Lease Losses	4,729	(2,800)
Loans and Leases Receivable, Allowance, ending balance	13,483	9,577
Loans and Leases Receivable, Allowance, Covered, ending balance	13,483	9,577
Receivables Acquired With Deteriorated Credit Quality, Allowance For Credit Losses	13,483	9,577
Receivables Acquired with Deteriorated Credit Quality	108,424	189,045
Loans held for investment, net	108,424	189,045
NonPCI and PCI Loans [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Loans and Leases Receivable Allowance Covered And Noncovered, beginning balance	115,111	84,455
Allowance for Loan and Lease Losses, Write-offs	(35,954)	(17,771)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	13,141	8,623
Provision for Loan and Lease Losses	64,940	39,804
Loans and Leases Receivable Allowance Covered And Noncovered, ending balance	157,238	115,111
Loans and Leases Receivable Net Of Deferred Income Covered And Noncovered	15,455,954	14,478,254
Mortgages [Member] | Non Purchased Credit Impaired Loans and Leases [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Loans and Leases Receivable, Allowance, beginning balance	36,654	25,097
Allowance for Loan and Lease Losses, Write-offs	(2,059)	(2,489)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	4,519	3,582
Provision for Loan and Lease Losses	(1,349)	10,464
Loans and Leases Receivable, Allowance, ending balance	37,765	36,654
Financing Receivable, Individually Evaluated for Impairment	6,851	1,458
Financing Receivable, Collectively Evaluated for Impairment	30,914	35,196
Financing Receivable, Individually Evaluated for Impairment	123,348	83,944
Financing Receivable, Collectively Evaluated for Impairment	5,494,608	5,604,119
Loans held for investment, net	5,617,956	5,688,063
Real Estate Construction [Member] | Non Purchased Credit Impaired Loans and Leases [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Loans and Leases Receivable, Allowance, beginning balance	7,137	4,248
Allowance for Loan and Lease Losses, Write-offs	0	0
Allowance for Loan and Lease Loss, Recovery of Bad Debts	673	1,082
Provision for Loan and Lease Losses	2,235	1,807
Loans and Leases Receivable, Allowance, ending balance	10,045	7,137
Financing Receivable, Individually Evaluated for Impairment	0	26
Financing Receivable, Collectively Evaluated for Impairment	10,045	7,111
Financing Receivable, Individually Evaluated for Impairment	7,257	8,003
Financing Receivable, Collectively Evaluated for Impairment	955,582	519,717
Loans held for investment, net	962,839	527,720
Commercial Portfolio Segment [Member] | Non Purchased Credit Impaired Loans and Leases [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Loans and Leases Receivable, Allowance, beginning balance	61,082	39,858
Allowance for Loan and Lease Losses, Write-offs	(32,210)	(13,354)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	7,794	3,399
Provision for Loan and Lease Losses	57,187	31,179
Loans and Leases Receivable, Allowance, ending balance	93,853	61,082
Financing Receivable, Individually Evaluated for Impairment	17,912	17,622
Financing Receivable, Collectively Evaluated for Impairment	75,941	43,460
Financing Receivable, Individually Evaluated for Impairment	103,431	74,680
Financing Receivable, Collectively Evaluated for Impairment	8,288,129	7,877,897
Loans held for investment, net	8,391,560	7,952,577
Consumer Portfolio Segment [Member] | Non Purchased Credit Impaired Loans and Leases [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Loans and Leases Receivable, Allowance, beginning balance	661	1,253
Allowance for Loan and Lease Losses, Write-offs	(823)	(156)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	116	410
Provision for Loan and Lease Losses	2,138	(846)
Loans and Leases Receivable, Allowance, ending balance	2,092	661
Financing Receivable, Individually Evaluated for Impairment	170	157
Financing Receivable, Collectively Evaluated for Impairment	1,922	504
Financing Receivable, Individually Evaluated for Impairment	394	1,672
Financing Receivable, Collectively Evaluated for Impairment	374,781	119,177
Loans held for investment, net	$ 375,175	$ 120,849