Loans and Leases (Details 7) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	$ 157,238
Balance, end of period	161,307
The ending balance of the loan and lease portfolio is composed of loans and leases:
Ending balance of loans and leases	15,556,689		$ 15,455,954
Non Purchased Credit Impaired Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	143,755	$ 105,534
Charge-offs	(20,928)	(5,373)
Recoveries	2,739	1,481
Provision	24,260	19,165
Balance, end of period	149,826	120,807
Amount of the allowance applicable to loans and leases:
impairment	13,427	30,040
impairment	136,399	90,767
The ending balance of the loan and lease portfolio is composed of loans and leases:
impairment	228,460	196,491
impairment	15,231,894	14,110,470
Ending balance of loans and leases	15,460,354	14,306,961	15,347,530
Purchased Credit Impaired Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	13,483
Balance, beginning of period	13,483	9,577
Charge-offs	(2,230)	(163)
Recoveries	0	0
Provision	228	140
Balance, end of period	11,481
Balance, end of period	11,481	9,554
Amount of the allowance applicable to loans and leases:
deteriorated credit quality	11,481	9,554
The ending balance of the loan and lease portfolio is composed of loans and leases:
deteriorated credit quality	96,335	176,556
Ending balance of loans and leases	96,335	176,556	108,424
NonPCI and PCI Loans
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	157,238	115,111
Charge-offs	(23,158)	(5,536)
Recoveries	2,739	1,481
Provision	24,488	19,305
Balance, end of period	161,307	130,361
The ending balance of the loan and lease portfolio is composed of loans and leases:
Total loans and leases	15,556,689	14,483,517
Real Estate Mortgage \| Non Purchased Credit Impaired Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	37,765	36,654
Charge-offs	(1,544)	(737)
Recoveries	230	999
Provision	(1,083)	(7,817)
Balance, end of period	35,368	29,099
Amount of the allowance applicable to loans and leases:
impairment	1,070	1,954
impairment	34,298	27,145
The ending balance of the loan and lease portfolio is composed of loans and leases:
impairment	118,275	90,830
impairment	5,768,694	5,539,467
Ending balance of loans and leases	5,886,969	5,630,297	5,617,956
Real Estate Construction and Land \| Non Purchased Credit Impaired Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	10,045	7,137
Charge-offs	0	0
Recoveries	8	152
Provision	423	(413)
Balance, end of period	10,476	6,876
Amount of the allowance applicable to loans and leases:
impairment	0	21
impairment	10,476	6,855
The ending balance of the loan and lease portfolio is composed of loans and leases:
impairment	6,683	7,945
impairment	1,101,553	567,528
Ending balance of loans and leases	1,108,236	575,473	962,839
Commercial \| Non Purchased Credit Impaired Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	93,853	61,082
Charge-offs	(19,285)	(4,045)
Recoveries	2,448	314
Provision	25,118	26,606
Balance, end of period	102,134	83,957
Amount of the allowance applicable to loans and leases:
impairment	12,267	27,902
impairment	89,867	56,055
The ending balance of the loan and lease portfolio is composed of loans and leases:
impairment	103,221	96,614
impairment	7,979,457	7,893,955
Ending balance of loans and leases	8,082,678	7,990,569	8,391,560
Consumer \| Non Purchased Credit Impaired Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	2,092	661
Charge-offs	(99)	(591)
Recoveries	53	16
Provision	(198)	789
Balance, end of period	1,848	875
Amount of the allowance applicable to loans and leases:
impairment	90	163
impairment	1,758	712
The ending balance of the loan and lease portfolio is composed of loans and leases:
impairment	281	1,102
impairment	382,190	109,520
Ending balance of loans and leases	$ 382,471	$ 110,622	$ 375,175

Financing Receivable, Allowance for Credit Loss, Additional Information, Portfolio Composition [Abstract]

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Loans and Leases Receivable Allowance Covered And Noncovered

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Loans and Leases Receivable Net Of Deferred Income Covered And Noncovered

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Receivables Acquired With Deteriorated Credit Quality, Allowance For Credit Losses

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Receivables Acquired with Deteriorated Credit Quality

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Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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