Fulton Financial (FULT) 10-Q 6 Nov 15 2015 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2015	Oct. 30, 2015
Document and Entity Information
Entity Registrant Name	FULTON FINANCIAL CORP
Entity Central Index Key	700,564
Trading Symbol	fult
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		174,031,000

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
ASSETS
Cash and due from banks	$ 93,803	$ 105,702
Interest-bearing deposits with other banks	510,943	358,130
Federal Reserve Bank and Federal Home Loan Bank stock	68,977	64,953
Loans held for sale	26,937	17,522
Available for sale investment securities	2,436,337	2,323,371
Loans, net of unearned income	13,536,361	13,111,716
Less: Allowance for loan losses	(167,136)	(184,144)
Net Loans	13,369,225	12,927,572
Premises and equipment	225,705	226,027
Accrued interest receivable	42,846	41,818
Goodwill and intangible assets	531,562	531,803
Other assets	531,724	527,869
Total Assets	17,838,059	17,124,767
LIABILITIES
Noninterest-bearing	3,906,228	3,640,623
Interest-bearing	10,178,166	9,726,883
Total Deposits	14,084,394	13,367,506
Short-term borrowings:
Federal funds purchased	5,527	6,219
Other short-term borrowings	426,104	323,500
Total Short-Term Borrowings	431,631	329,719
Accrued interest payable	14,727	18,045
Other liabilities	301,970	273,419
Federal Home Loan Bank advances and long-term debt	979,433	1,139,413
Total Liabilities	15,812,155	15,128,102
SHAREHOLDERS’ EQUITY
Common stock, $2.50 par value, 600 million shares authorized, 218.6 million shares issued in 2015 and 218.2 million shares issued in 2014	546,444	545,555
Additional paid-in capital	1,447,569	1,420,523
Retained earnings	622,237	558,810
Accumulated other comprehensive loss	(13,219)	(17,722)
Treasury stock, at cost, 44.8 million shares in 2015 and 39.3 million shares in 2014	(577,127)	(510,501)
Total Shareholders’ Equity	2,025,904	1,996,665
Total Liabilities and Shareholders’ Equity	$ 17,838,059	$ 17,124,767

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Common stock, par value	$ 2.5	$ 2.5
Common stock, shares authorized	600,000,000	600,000,000
Common stock, shares issued	218,600,000	218,200,000
Treasury stock, shares	44,800,000	39,300,000

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
INTEREST INCOME
Loans, including fees	$ 131,804	$ 133,741	$ 391,491	$ 397,011
Investment securities:
Taxable	11,252	12,278	33,478	37,962
Tax-exempt	1,904	2,219	5,872	6,865
Dividends	190	339	834	996
Loans held for sale	194	237	632	585
Other interest income	884	976	3,922	3,065
Total Interest Income	146,228	149,790	436,229	446,484
INTEREST EXPENSE
Deposits	10,217	8,998	30,093	25,579
Short-term borrowings	92	297	272	1,470
Long-term debt	10,225	11,129	33,669	32,606
Total Interest Expense	20,534	20,424	64,034	59,655
Net Interest Income	125,694	129,366	372,195	386,829
Provision for credit losses	1,000	3,500	(500)	9,500
Net Interest Income After Provision for Credit Losses	124,694	125,866	372,695	377,329
NON-INTEREST INCOME
Service charges on deposit accounts	12,982	12,801	37,188	37,064
Investment management and trust services	11,237	11,120	33,137	33,417
Other service charges and fees	10,965	9,954	31,316	29,407
Mortgage banking income	3,864	4,038	13,891	13,384
Investment securities gains, net:
Net gains on sales of investment securities	1,730	99	8,290	1,223
Net other-than-temporary impairment losses	0	(18)	0	(30)
Investment securities gains, net	1,730	81	8,290	1,193
Other	3,996	3,906	12,178	10,813
Total Non-Interest Income	44,774	41,900	136,000	125,278
NON-INTEREST EXPENSE
Salaries and employee benefits	65,308	62,434	195,365	185,623
Net occupancy expense	10,710	11,582	36,211	36,649
Other outside services	7,373	8,632	21,248	19,684
Loss on redemption of trust preferred securities	5,626	0	5,626	0
Data processing	5,105	4,689	14,767	12,816
Software	3,984	3,353	10,678	9,487
Equipment expense	3,595	3,307	10,888	10,269
Marketing	2,867	2,882	8,574	8,186
Supplies and postage	2,828	3,252	8,430	9,715
Telecommunications	2,708	2,560	7,803	7,337
Marketing	2,102	1,798	5,570	5,719
Telecommunications	1,587	1,587	4,920	5,193
Operating risk loss	1,136	1,242	2,637	3,786
Other real estate owned and repossession expense	1,016	1,303	2,507	3,034
Intangible amortization	5	314	241	944
Other	8,939	6,863	26,256	23,084
Total Non-Interest Expense	124,889	115,798	361,721	341,526
Income Before Income Taxes	44,579	51,968	146,974	161,081
Income taxes	10,328	13,402	36,007	41,136
Net Income	$ 34,251	$ 38,566	$ 110,967	$ 119,945
PER SHARE:
Net Income (Basic) (in dollars per share)	$ 0.20	$ 0.21	$ 0.63	$ 0.64
Net Income (Diluted) (in dollars per share)	0.20	0.21	0.63	0.64
Cash Dividends (in dollars per share)	$ 0.09	$ 0.08	$ 0.27	$ 0.24

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Statement of Comprehensive Income [Abstract]
Net Income	$ 34,251	$ 38,566	$ 110,967	$ 119,945
Other Comprehensive Income (Loss), net of tax:
Unrealized gain (loss) on securities	7,857	(3,011)	5,841	23,912
Reclassification adjustment for postretirement amendment gains included in net income	0	0	0	(944)
Reclassification adjustment for securities gains included in net income	(1,124)	(52)	(5,388)	(775)
Reclassification adjustment for loss on derivative financial instruments included in net income	2,456	0	2,456	0
Non-credit related unrealized gain on other-than-temporarily impaired debt securities	0	138	125	650
Amortization of unrealized loss on derivative financial instruments	3	34	71	102
Unrecognized postretirement income arising due to plan amendment	0	0	0	2,144
Amortization of net unrecognized pension and postretirement items	466	104	1,398	304
Other Comprehensive Income (Loss)	9,658	(2,787)	4,503	25,393
Total Comprehensive Income	$ 43,909	$ 35,779	$ 115,470	$ 145,338

Consolidated Statements of Shar

Consolidated Statements of Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Share Repurchase Program [Member]	Accelerated Stock Repurchase Program [Member]	Common Stock [Member]	Common Stock [Member]Share Repurchase Program [Member]	Common Stock [Member]Accelerated Stock Repurchase Program [Member]	Additional Paid-In Capital [Member]	Additional Paid-In Capital [Member]Accelerated Stock Repurchase Program [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income [Member]	Treasury Stock [Member]	Treasury Stock [Member]Share Repurchase Program [Member]	Treasury Stock [Member]Accelerated Stock Repurchase Program [Member]
Beginning Balance at Dec. 31, 2013	$ 2,063,187			$ 544,568			$ 1,432,974		$ 463,843	$ (37,341)	$ (340,857)
Beginning Balance (in shares) at Dec. 31, 2013				192,652
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	119,945								119,945
Other comprehensive income	25,393									25,393
Stock issued, including related tax benefits	5,465			$ 639			1,059				3,767
Stock issued, including related tax benefits (in shares)				506
Stock-based compensation awards	4,310						4,310
Acquisition of treasury stock (in shares)				(8,000)
Acquisition of treasury stock	(95,255)										(95,255)
Common stock cash dividends	(45,039)								(45,039)
Ending Balance at Sep. 30, 2014	2,078,006			$ 545,207			1,438,343		538,749	(11,948)	(432,345)
Ending Balance (in shares) at Sep. 30, 2014				185,158
Beginning Balance at Dec. 31, 2014	1,996,665			$ 545,555			1,420,523		558,810	(17,722)	(510,501)
Beginning Balance (in shares) at Dec. 31, 2014				178,924
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	110,967								110,967
Other comprehensive income	4,503									4,503
Stock issued, including related tax benefits	6,938			$ 889			2,675				3,374
Stock issued, including related tax benefits (in shares)				613
Stock-based compensation awards	$ 4,371						4,371
Acquisition of treasury stock (in shares)	(4,000)				(3,976)	(1,790)
Acquisition of treasury stock		$ (50,000)	$ 0					$ 20,000				$ (50,000)	$ (20,000)
Common stock cash dividends	$ (47,540)								(47,540)
Ending Balance at Sep. 30, 2015	$ 2,025,904			$ 546,444			$ 1,447,569		$ 622,237	$ (13,219)	$ (577,127)
Ending Balance (in shares) at Sep. 30, 2015				173,771

Consolidated Statements of Sha7

Consolidated Statements of Shareholders' Equity (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Statement of Stockholders' Equity [Abstract]
Cash dividends per share	$ 0.09	$ 0.08	$ 0.27	$ 0.24

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net Income	$ 110,967	$ 119,945
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for credit losses	(500)	9,500
Depreciation and amortization of premises and equipment	20,302	18,412
Net amortization of investment securities premiums	5,369	4,399
Net gains on sales of investment securities	(8,290)	(1,193)
Net increase in loans held for sale	(9,415)	(3,861)
Amortization of intangible assets	241	944
Stock-based compensation	4,371	4,310
Excess tax benefits from stock-based compensation	(86)	(54)
Loss on redemption of trust preferred securities	5,626	0
(Increase) decrease in accrued interest receivable	(1,028)	493
Decrease (increase) in other assets	6,683	(1,909)
(Decrease) increase in accrued interest payable	(3,318)	2,207
Increase (decrease) in other liabilities	3,995	(5,315)
Total adjustments	23,950	27,933
Net cash provided by operating activities	134,917	147,878
CASH FLOWS FROM INVESTING ACTIVITIES:
Proceeds from sales of securities available for sale	29,309	15,219
Proceeds from maturities of securities available for sale	317,813	273,688
Purchase of securities available for sale	(444,111)	(164,676)
Increase in short-term investments	(156,837)	(129,418)
Net increase in loans	(440,681)	(271,494)
Net purchases of premises and equipment	(19,980)	(16,832)
Net cash used in investing activities	(714,487)	(293,513)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net increase in demand and savings deposits	852,611	768,979
Net (decrease) increase in time deposits	(135,723)	73,462
Increase (decrease) in short-term borrowings	101,912	(693,677)
Additions to long-term debt	347,778	140,000
Repayments of long-term debt	(509,606)	(5,295)
Net proceeds from issuance of common stock	6,852	5,411
Excess tax benefits from stock-based compensation	86	54
Dividends paid	(46,239)	(45,638)
Acquisition of treasury stock	(50,000)	(95,255)
Net cash provided by financing activities	567,671	148,041
Net (Decrease) Increase in Cash and Due From Banks	(11,899)	2,406
Cash and Due From Banks at Beginning of Period	105,702	218,540
Cash and Due From Banks at End of Period	93,803	220,946
Cash paid during the period for:
Interest	67,352	57,448
Income taxes	$ 9,168	$ 16,632

Basis of Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited consolidated financial statements of Fulton Financial Corporation (the "Corporation") have been prepared in conformity with U.S. generally accepted accounting principles ("U.S. GAAP") for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and notes required by U.S. GAAP for complete financial statements. The preparation of financial statements in accordance with U.S. GAAP requires management to make estimates and assumptions that affect the amounts of assets and liabilities as of the date of the financial statements as well as revenues and expenses during the period. Actual results could differ from those estimates. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included. These consolidated financial statements should be read in conjunction with the audited consolidated financial statements and the notes thereto included in the Company's Annual Report on Form 10-K for the year ended December 31, 2014. Operating results for the three and nine months ended September 30, 2015 are not necessarily indicative of the results that may be expected for the year ending December 31, 2015 . The Corporation evaluates subsequent events through the date of filing of this Form 10-Q with the Securities and Exchange Commission ("SEC"). Recent Accounting Standards Effective January 1, 2015, the Corporation adopted the Financial Accounting Standards Board's ("FASB") Accounting Standards Codification ("ASC") Update 2014-01, "Accounting for Investments in Qualified Affordable Housing Projects." ASC Update 2014-01 provides guidance on accounting for investments made by a reporting entity in flow-through limited liability entities that manage or invest in affordable housing projects that qualify for the low income housing tax credit. The Corporation has made certain investments in partnerships that generate tax credits under various federal programs which promote investment in low and moderate income housing and local economic development. The net income tax benefit associated with these investments, which consists of the amortization of the investments net of tax benefit, and the income tax credits earned on the investments recorded in income taxes on the consolidated income statements was $2.3 million and $2.1 million for the three months ended September 30, 2015 and 2014, respectively, and $7.1 million and $7.4 million for the nine months ended September 30, 2015 and 2014, respectively. As of September 30, 2015 and December 31, 2014, the Corporation’s tax credit investments, included in other assets on the consolidated balance sheets, totaled $164.0 million and $155.6 million , respectively. The adoption of this ASC update did not have a material impact on the Corporation's consolidated financial statements for the three or nine months ended September 30, 2015 or 2014. In February 2015, the FASB issued ASC Update 2015-02, "Consolidation: Amendments to the Consolidation Analysis." ASC Update 2015-02 changes the way reporting enterprises evaluate whether: (a) they should consolidate limited partnerships and similar entities, (b) fees paid to a decision maker or service provider are variable interests in a variable interest entity ("VIE"), and (c) variable interests in a VIE held by related parties of the reporting enterprise require the reporting enterprise to consolidate the VIE. ASC Update 2015-02 is effective for public business entities' annual and interim reporting periods beginning after December 15, 2015, with earlier adoption permitted. The Corporation intends to adopt this standards update effective with its March 31, 2016 quarterly report on Form 10-Q, and does not expect the adoption of ASC Update 2015-02 to have a material impact on its consolidated financial statements. In April 2015, the FASB issued ASC Update 2015-03, "Interest - Imputation of Interest" and updated ASC Update 2015-03 with the issuance of ASC Update 2015-15, “Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements,” in August of 2015. ASC Update 2015-03 simplifies the presentation of debt issuances costs. Debt issuance costs related to a recognized debt liability will be presented on the balance sheet as a direct deduction from the debt liability, similar to the presentation of debt discounts. Under current U.S. GAAP, debt issuance costs are reported on the balance sheet as assets. The costs will continue to be amortized to interest expense using the effective interest method. ASC Update 2015-03 is effective for public business entities' annual and interim reporting periods beginning after December 15, 2015, with earlier adoption permitted. The Corporation intends to adopt this standards update effective with its March 31, 2016 quarterly report on Form 10-Q and does not expect the adoption of ASC Update 2015-03 to have a material impact on its consolidated financial statements. In April 2015, the FASB issued ASC Update 2015-05, "Customer's Accounting for Fees Paid in a Cloud Computing Arrangement." ASC Update 2015-05 provides explicit guidance to determine when a customer's fees paid in a cloud computing arrangement is for the acquisition of software licenses, services, or both. ASC Update 2015-05 is effective for public business entities' annual and interim reporting periods beginning after December 15, 2015, with earlier adoption permitted. The Corporation intends to adopt this standards update effective with its March 31, 2016 quarterly report on Form 10-Q and does not expect the adoption of ASC Update 2015-05 to have a material impact on its consolidated financial statements.

Net Income Per Share

Net Income Per Share	9 Months Ended
	Sep. 30, 2015
Earnings Per Share [Abstract]
Net Income Per Share	Net Income Per Share Basic net income per share is calculated as net income divided by the weighted average number of shares outstanding. Diluted net income per share is calculated as net income divided by the weighted average number of shares outstanding plus the incremental number of shares added as a result of converting common stock equivalents, calculated using the treasury stock method. The Corporation’s common stock equivalents consist of outstanding stock options, restricted stock, restricted stock units ("RSUs") and performance based restricted stock units ("PSUs"). PSUs are required to be included in weighted average shares outstanding if performance measures, as defined in each PSU award agreement, are met as of the end of the period. A reconciliation of weighted average shares outstanding used to calculate basic net income per share and diluted net income per share follows: Three months ended September 30 Nine months ended September 30 2015 2014 2015 2014 (in thousands) Weighted average shares outstanding (basic) 174,338 186,109 176,399 187,893 Impact of common stock equivalents 1,004 846 1,029 970 Weighted average shares outstanding (diluted) 175,342 186,955 177,428 188,863 For the three and nine months ended September 30, 2015 , 1.5 million and 1.8 million stock options, respectively, were excluded from the diluted net income per share computation as their effect would have been anti-dilutive. For the three and nine months ended September 30, 2014 , 2.5 million and 2.9 million stock options, respectively, were excluded from the diluted net income per share computation as their effect would have been anti-dilutive.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income	9 Months Ended
	Sep. 30, 2015
Equity [Abstract]
Accumulated Other Comprehensive Income	Accumulated Other Comprehensive Income The following table presents changes in other comprehensive income: Before-Tax Amount Tax Effect Net of Tax Amount (in thousands) Three months ended September 30, 2015 Unrealized gain on securities $ 12,088 $ (4,231 ) $ 7,857 Reclassification adjustment for securities gains included in net income (1) (1,730 ) 606 (1,124 ) Reclassification adjustment for loss on derivative financial instruments included in net income (2) 3,778 (1,322 ) 2,456 Amortization of unrealized loss on derivative financial instruments 5 (2 ) 3 Amortization of net unrecognized pension and postretirement items (3) 717 (251 ) 466 Total Other Comprehensive Income $ 14,858 $ (5,200 ) $ 9,658 Three months ended September 30, 2014 Unrealized loss on securities $ (4,629 ) $ 1,618 $ (3,011 ) Reclassification adjustment for securities gains included in net income (1) (81 ) 29 (52 ) Non-credit related unrealized gains on other-than-temporarily impaired debt securities 212 (74 ) 138 Amortization of unrealized loss on derivative financial instruments 52 (18 ) 34 Amortization of net unrecognized pension and postretirement items (3) 160 (56 ) 104 Total Other Comprehensive Loss $ (4,286 ) $ 1,499 $ (2,787 ) Nine months ended September 30, 2015 Unrealized gain on securities $ 8,987 $ (3,146 ) $ 5,841 Reclassification adjustment for securities gains included in net income (1) (8,290 ) 2,902 (5,388 ) Reclassification adjustment for loss on derivative financial instruments included in net income (2) 3,778 (1,322 ) 2,456 Non-credit related unrealized gains (losses) on other-than-temporarily impaired debt securities 192 (67 ) 125 Amortization of unrealized loss on derivative financial instruments 110 (39 ) 71 Amortization of net unrecognized pension and postretirement items (3) 2,151 (753 ) 1,398 Total Other Comprehensive Income $ 6,928 $ (2,425 ) $ 4,503 Nine months ended September 30, 2014 Unrealized gain on securities $ 36,790 $ (12,878 ) $ 23,912 Reclassification adjustment for securities gains included in net income (1) (1,193 ) 418 (775 ) Reclassification adjustment for postretirement gains included in net income (3) (1,452 ) 508 (944 ) Non-credit related unrealized gains (losses) on other-than-temporarily impaired debt securities 1,000 (350 ) 650 Amortization of unrealized loss on derivative financial instruments 157 (55 ) 102 Unrecognized pension and postretirement income 3,291 (1,147 ) 2,144 Amortization of net unrecognized pension and postretirement items (3) 469 (165 ) 304 Total Other Comprehensive Income $ 39,062 $ (13,669 ) $ 25,393 (1) Amounts reclassified out of accumulated other comprehensive income. Before-tax amounts included within "Investment securities gains, net" on the consolidated statements of income. See Note 4, "Investment Securities," for additional details. (2) Amount reclassified out of accumulated other comprehensive income. Before-tax amount included within "Loss on Redemption of Trust Preferred Securities" on the consolidated statements of income. See Note 15, "Long-Term Debt," for additional details. (3) Amounts reclassified out of accumulated other comprehensive income. Before-tax amounts included within "Salaries and employee benefits" on the consolidated statements of income. See Note 8, "Employee Benefit Plans," for additional details. The following table presents changes in each component of accumulated other comprehensive income, net of tax: Unrealized Gains (Losses) on Investment Securities Not Other-Than-Temporarily Impaired Unrealized Non-Credit Gains (Losses) on Other-Than-Temporarily Impaired Debt Securities Unrealized Effective Portions of Losses on Forward-Starting Interest Rate Swaps Unrecognized Pension and Postretirement Plan Income (Costs) Total (in thousands) Three months ended September 30, 2015 Balance at June 30, 2015 $ 830 $ 344 $ (2,478 ) $ (21,573 ) $ (22,877 ) Other comprehensive loss before reclassifications 7,857 — — — 7,857 Amounts reclassified from accumulated other comprehensive income (loss) (1,124 ) — 3 466 (655 ) Reclassification adjustment for loss on derivative financial instruments included in net income — — — 2,456 — — 2,456 Balance at September 30, 2015 $ 7,563 $ 344 $ (19 ) $ (21,107 ) $ (13,219 ) Three months ended September 30, 2014 Balance at June 30, 2014 $ (580 ) $ 1,434 $ (2,614 ) $ (7,401 ) $ (9,161 ) Other comprehensive income before reclassifications (3,011 ) 138 — — (2,873 ) Amounts reclassified from accumulated other comprehensive income (loss) (63 ) 11 34 104 86 Balance at September 30, 2014 $ (3,654 ) $ 1,583 $ (2,580 ) $ (7,297 ) $ (11,948 ) Nine months ended September 30, 2015 Balance at December 31, 2014 $ 5,980 $ 1,349 $ (2,546 ) $ (22,505 ) $ (17,722 ) Other comprehensive income before reclassifications 5,841 125 — — 5,966 Amounts reclassified from accumulated other comprehensive income (loss) (4,258 ) (1,130 ) 71 1,398 (3,919 ) Reclassification adjustment for loss on derivative financial instruments included in net income — — 2,456 — 2,456 Balance at September 30, 2015 $ 7,563 $ 344 $ (19 ) $ (21,107 ) $ (13,219 ) Nine months ended September 30, 2014 Balance at December 31, 2013 $ (27,510 ) $ 1,652 $ (2,682 ) $ (8,801 ) $ (37,341 ) Other comprehensive income before reclassifications 23,912 650 — 2,144 26,706 Amounts reclassified from accumulated other comprehensive income (loss) (56 ) (719 ) 102 (640 ) (1,313 ) Balance at September 30, 2014 $ (3,654 ) $ 1,583 $ (2,580 ) $ (7,297 ) $ (11,948 )

Investment Securities

Investment Securities	9 Months Ended
	Sep. 30, 2015
Investments, Debt and Equity Securities [Abstract]
Investment Securities	Investment Securities The following table presents the amortized cost and estimated fair values of investment securities, which were all classified as available for sale: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (in thousands) September 30, 2015 Equity securities $ 16,087 $ 7,453 $ (8 ) $ 23,532 U.S. Government sponsored agency securities 48,320 231 — 48,551 State and municipal securities 234,868 5,430 (62 ) 240,236 Corporate debt securities 102,297 2,935 (5,291 ) 99,941 Collateralized mortgage obligations 879,738 5,638 (11,077 ) 874,299 Mortgage-backed securities 1,036,193 16,845 (1,133 ) 1,051,905 Auction rate securities 106,661 — (8,788 ) 97,873 $ 2,424,164 $ 38,532 $ (26,359 ) $ 2,436,337 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (in thousands) December 31, 2014 Equity securities $ 33,469 $ 14,167 $ (13 ) $ 47,623 U.S. Government securities 200 — — 200 U.S. Government sponsored agency securities 209 5 — 214 State and municipal securities 238,250 7,231 (266 ) 245,215 Corporate debt securities 99,016 5,126 (6,108 ) 98,034 Collateralized mortgage obligations 917,395 5,705 (20,787 ) 902,313 Mortgage-backed securities 914,797 16,978 (2,944 ) 928,831 Auction rate securities 108,751 — (7,810 ) 100,941 $ 2,312,087 $ 49,212 $ (37,928 ) $ 2,323,371 Securities carried at $1.8 billion as of September 30, 2015 and $1.7 billion as of December 31, 2014 were pledged as collateral to secure public and trust deposits and customer repurchase agreements. Equity securities include common stocks of financial institutions (estimated fair value of $22.4 million at September 30, 2015 and $41.8 million at December 31, 2014 ) and other equity investments (estimated fair value of $1.1 million at September 30, 2015 and $5.8 million at December 31, 2014 ). As of September 30, 2015 , the financial institutions stock portfolio had a cost basis of $15.1 million and an estimated fair value of $22.4 million , including an investment in a single financial institution with a cost basis of $8.5 million and an estimated fair value of $12.8 million . The estimated fair value of this investment accounted for 57.1% of the estimated fair value of the Corporation's investments in the common stocks of publicly traded financial institutions. No other investment within the financial institutions stock portfolio exceeded 5% of the portfolio's estimated fair value. The amortized cost and estimated fair values of debt securities as of September 30, 2015 , by contractual maturity, are shown in the following table. Actual maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. Amortized Estimated (in thousands) Due in one year or less $ 62,247 $ 63,023 Due from one year to five years 104,989 107,283 Due from five years to ten years 132,930 136,571 Due after ten years 191,980 179,724 492,146 486,601 Collateralized mortgage obligations 879,738 874,299 Mortgage-backed securities 1,036,193 1,051,905 $ 2,408,077 $ 2,412,805 The following table presents information related to the gross realized gains and losses on the sales of equity and debt securities: Gross Gross Other-than- Net Gains (Losses) Three months ended September 30, 2015 (in thousands) Equity securities $ 1,730 $ — $ — $ 1,730 Debt securities — — — — Total $ 1,730 $ — $ — $ 1,730 Three months ended September 30, 2014 Equity securities $ 99 $ — $ — $ 99 Debt securities — — (18 ) (18 ) Total $ 99 $ — $ (18 ) $ 81 Nine months ended September 30, 2015 Equity securities $ 5,990 $ — $ — $ 5,990 Debt securities 2,300 — — 2,300 Total $ 8,290 $ — $ — $ 8,290 Nine months ended September 30, 2014 Equity securities $ 100 $ — $ (12 ) $ 88 Debt securities 1,446 (323 ) (18 ) 1,105 Total $ 1,546 $ (323 ) $ (30 ) $ 1,193 The following table presents a summary of the cumulative credit related other-than-temporary impairment charges, recognized as components of earnings, for debt securities held by the Corporation at September 30, 2015 and 2014: Three months ended September 30 Nine months ended September 30 2015 2014 2015 2014 (in thousands) Balance of cumulative credit losses on debt securities, beginning of period $ (11,510 ) $ (17,214 ) $ (16,242 ) $ (20,691 ) Additions for credit losses recorded which were not previously recognized as components of earnings — (18 ) — (18 ) Reductions for securities sold during the period — — 4,730 3,472 Reductions for increases in cash flows expected to be collected that are recognized over the remaining life of the security — — 2 5 Balance of cumulative credit losses on debt securities, end of period $ (11,510 ) $ (17,232 ) $ (11,510 ) $ (17,232 ) The following table presents the gross unrealized losses and estimated fair values of investments, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position at September 30, 2015 : Less than 12 months 12 months or longer Total Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses (in thousands) U.S. Government sponsored agency securities $ — $ — $ — $ — $ — $ — State and municipal securities 11,892 (62 ) — — 11,892 (62 ) Corporate debt securities 7,968 (15 ) 33,718 (5,276 ) 41,686 (5,291 ) Collateralized mortgage obligations 30,723 (62 ) 493,703 (11,015 ) 524,426 (11,077 ) Mortgage-backed securities 161,097 (443 ) 67,071 (690 ) 228,168 (1,133 ) Auction rate securities — — 97,873 (8,788 ) 97,873 (8,788 ) Total debt securities 211,680 (582 ) 692,365 (25,769 ) 904,045 (26,351 ) Equity securities — — 13 (8 ) 13 (8 ) $ 211,680 $ (582 ) $ 692,378 $ (25,777 ) $ 904,058 $ (26,359 ) The Corporation’s collateralized mortgage obligations and mortgage-backed securities have contractual terms that generally do not permit the issuer to settle the securities at a price less than the amortized cost of the investment. Because the decline in market value of these securities is attributable to changes in interest rates and not credit quality, and because the Corporation does not have the intent to sell and does not believe it will more likely than not be required to sell any of these securities prior to a recovery of their fair value to amortized cost, the Corporation does not consider these investments to be other-than-temporarily impaired as of September 30, 2015 . The unrealized holding losses on auction rate securities (auction rate certificates, or "ARCs"), are attributable to liquidity issues resulting from the failure of periodic auctions. The Corporation had previously purchased ARCs for investment management and trust customers as short-term investments with fair values that could be derived based on periodic auctions under normal market conditions. During 2008 and 2009, the Corporation purchased ARCs from these customers due to the failure of these periodic auctions, which made these previously short-term investments illiquid. As of September 30, 2015 , all of the ARCs were rated above investment grade, with approximately $5.4 million , or 6% , "AAA" rated and $92.4 million , or 94% , "AA" rated. All of the loans underlying the ARCs have principal payments which are guaranteed by the federal government. As of September 30, 2015 , all ARCs were current and making scheduled interest payments. Based on management’s evaluations, ARCs with an estimated fair value of $97.9 million were not subject to any other-than-temporary impairment charges as of September 30, 2015 . The Corporation does not have the intent to sell and does not believe it will more likely than not be required to sell any of these securities prior to a recovery of their fair value to amortized cost, which may be at maturity. For its investments in equity securities, particularly its investments in stocks of financial institutions, management evaluates the near-term prospects of the issuers in relation to the severity and duration of the impairment. Based on that evaluation and the Corporation’s ability and intent to hold those investments for a reasonable period of time sufficient for a recovery of fair value, the Corporation does not consider those investments with unrealized holding losses as of September 30, 2015 to be other-than-temporarily impaired. The majority of the Corporation's available for sale corporate debt securities are issued by financial institutions. The following table presents the amortized cost and estimated fair value of corporate debt securities: September 30, 2015 December 31, 2014 Amortized cost Estimated fair value Amortized cost Estimated fair value (in thousands) Single-issuer trust preferred securities $ 46,624 $ 41,787 $ 47,569 $ 42,016 Subordinated debt 51,625 53,576 47,530 50,023 Pooled trust preferred securities — 530 2,010 4,088 Corporate debt securities issued by financial institutions 98,249 95,893 97,109 96,127 Other corporate debt securities 4,048 4,048 1,907 1,907 Available for sale corporate debt securities $ 102,297 $ 99,941 $ 99,016 $ 98,034 The Corporation’s investments in single-issuer trust preferred securities had an unrealized loss of $4.8 million at September 30, 2015 . The Corporation did not record any other-than-temporary impairment charges for single-issuer trust preferred securities during the three or nine months ended September 30, 2015 or 2014 . Seven of the Corporation's 19 single-issuer trust preferred securities were rated below investment grade by at least one ratings agency, with an amortized cost of $14.5 million and an estimated fair value of $13.2 million at September 30, 2015 . All of the single-issuer trust preferred securities rated below investment grade were rated "BB" or "Ba". Two single-issuer trust preferred securities with an amortized cost of $3.7 million and an estimated fair value of $2.7 million at September 30, 2015 were not rated by any ratings agency. During the nine months ended September 30, 2015 , the Corporation sold three pooled trust preferred securities with a total amortized cost of $1.9 million , for a gain of $2.3 million . As of September 30, 2015 , both of the Corporation's remaining pooled trust preferred securities, with an amortized cost of $0 and an estimated fair value of $530,000 , were rated below investment grade by at least one ratings agency, with ratings ranging from "C" to "Ca". The class of securities held by the Corporation was below the most senior tranche, with the Corporation’s interests being subordinate to other investors in the pool. The Corporation determines the fair value of pooled trust preferred securities based on quotes provided by third-party brokers. The amortized cost of pooled trust preferred securities is the purchase price of the securities, net of cumulative credit related other-than-temporary impairment charges, determined using an expected cash flows model. The most significant input to the expected cash flows model is the expected payment deferral rate for each pooled trust preferred security. The Corporation evaluates the financial metrics, such as capital ratios and non-performing assets ratios, of the individual financial institution issuers that comprise each pooled trust preferred security to estimate its expected deferral rate. Based on management’s evaluations, corporate debt securities with a fair value of $99.9 million were not subject to any other-than-temporary impairment charges as of September 30, 2015 . The Corporation does not have the intent to sell and does not believe it will more likely than not be required to sell any of these securities prior to a recovery of their fair value to amortized cost, which may be at maturity.

Loans and Allowance for Credit

Loans and Allowance for Credit Losses	9 Months Ended
	Sep. 30, 2015
Receivables [Abstract]
Loans, Notes, Trade and Other Receivables Disclosure [Text Block]	Loans and Allowance for Credit Losses Loans, Net of Unearned Income Loans, net of unearned income are summarized as follows: September 30, December 31, 2014 (in thousands) Real-estate - commercial mortgage $ 5,339,928 $ 5,197,155 Commercial - industrial, financial and agricultural 3,929,908 3,725,567 Real-estate - home equity 1,693,649 1,736,688 Real-estate - residential mortgage 1,382,085 1,377,068 Real-estate - construction 769,565 690,601 Consumer 271,696 265,431 Leasing and other 161,911 127,562 Overdrafts 2,614 4,021 Loans, gross of unearned income 13,551,356 13,124,093 Unearned income (14,995 ) (12,377 ) Loans, net of unearned income $ 13,536,361 $ 13,111,716 Allowance for Credit Losses The allowance for credit losses consists of the allowance for loan losses and the reserve for unfunded lending commitments. The allowance for loan losses represents management’s estimate of incurred losses in the loan portfolio as of the balance sheet date and is recorded as a reduction to loans. The reserve for unfunded lending commitments represents management’s estimate of incurred losses in its unfunded loan commitments and is recorded in other liabilities on the consolidated balance sheet. The allowance for credit losses is increased by charges to expense, through the provision for credit losses, and decreased by charge-offs, net of recoveries. The Corporation’s allowance for credit losses includes: (1) specific allowances allocated to loans evaluated for impairment under the FASB's ASC Section 310-10-35; and (2) allowances calculated for pools of loans measured for impairment under FASB ASC Subtopic 450-20. The Corporation segments its loan portfolio by general loan type, or "portfolio segments," as presented in the table under the heading, "Loans, Net of Unearned Income," above. Certain portfolio segments are further disaggregated and evaluated collectively for impairment based on "class segments," which are largely based on the type of collateral underlying each loan. Commercial loans include loans secured by collateral and unsecured loans. Construction loan class segments include loans secured by commercial real estate, loans to commercial borrowers secured by residential real estate and loans to individuals secured by residential real estate. Consumer loan class segments include direct consumer installment loans and indirect automobile loans. The following table presents the components of the allowance for credit losses: September 30, December 31, (in thousands) Allowance for loan losses $ 167,136 $ 184,144 Reserve for unfunded lending commitments 2,259 1,787 Allowance for credit losses $ 169,395 $ 185,931 The following table presents the activity in the allowance for credit losses: Three months ended September 30 Nine months ended September 30 2015 2014 2015 2014 (in thousands) Balance at beginning of period $ 169,453 $ 193,442 $ 185,931 $ 204,917 Loans charged off (5,561 ) (9,604 ) (26,697 ) (31,348 ) Recoveries of loans previously charged off 4,503 3,770 10,661 8,039 Net loans charged off (1,058 ) (5,834 ) (16,036 ) (23,309 ) Provision for credit losses 1,000 3,500 (500 ) 9,500 Balance at end of period $ 169,395 $ 191,108 $ 169,395 $ 191,108 The following table presents the activity in the allowance for loan losses by portfolio segment: Real Estate - Commercial Mortgage Commercial - Industrial, Financial and Agricultural Real Estate - Home Equity Real Estate - Residential Mortgage Real Estate - Construction Consumer Leasing and other and overdrafts Unallocated Total (in thousands) Three months ended September 30, 2015 Balance at June 30, 2015 $ 50,680 $ 49,170 $ 22,506 $ 22,787 $ 7,749 $ 2,608 $ 1,615 $ 10,370 $ 167,485 Loans charged off (660 ) (1,640 ) (940 ) (1,035 ) (114 ) (650 ) (522 ) — (5,561 ) Recoveries of loans previously charged off 842 1,598 304 201 898 314 346 — 4,503 Net loans charged off 182 (42 ) (636 ) (834 ) 784 (336 ) (176 ) — (1,058 ) Provision for loan losses (1) 825 (405 ) 180 (609 ) (964 ) 282 223 1,177 709 Balance at September 30, 2015 $ 51,687 $ 48,723 $ 22,050 $ 21,344 $ 7,569 $ 2,554 $ 1,662 $ 11,547 $ 167,136 Three months ended September 30, 2014 Balance at June 30, 2014 $ 49,842 $ 49,084 $ 32,041 $ 32,744 $ 11,331 $ 3,306 $ 1,851 $ 11,486 $ 191,685 Loans charged off (1,557 ) (5,167 ) (1,492 ) (231 ) (313 ) (538 ) (306 ) — (9,604 ) Recoveries of loans previously charged off 1,167 1,013 336 95 470 448 241 — 3,770 Net loans charged off (390 ) (4,154 ) (1,156 ) (136 ) 157 (90 ) (65 ) — (5,834 ) Provision for loan losses (1) (278 ) 6,110 406 397 (312 ) 244 180 (3,121 ) 3,626 Balance at September 30, 2014 $ 49,174 $ 51,040 $ 31,291 $ 33,005 $ 11,176 $ 3,460 $ 1,966 $ 8,365 $ 189,477 Nine months ended September 30, 2015 Balance at December 31, 2014 $ 53,493 $ 51,378 $ 28,271 $ 29,072 $ 9,756 $ 3,015 $ 1,799 $ 7,360 $ 184,144 Loans charged off (3,011 ) (14,669 ) (2,578 ) (3,099 ) (201 ) (1,787 ) (1,352 ) — (26,697 ) Recoveries of loans previously charged off 1,729 3,855 744 547 2,276 923 587 — 10,661 Net loans charged off (1,282 ) (10,814 ) (1,834 ) (2,552 ) 2,075 (864 ) (765 ) — (16,036 ) Provision for loan losses (1) (524 ) 8,159 (4,387 ) (5,176 ) (4,262 ) 403 628 4,187 (972 ) Balance at September 30, 2015 $ 51,687 $ 48,723 $ 22,050 $ 21,344 $ 7,569 $ 2,554 $ 1,662 $ 11,547 $ 167,136 Nine months ended September 30, 2014 Balance at December 31, 2013 $ 55,659 $ 50,330 $ 28,222 $ 33,082 $ 12,649 $ 3,260 $ 3,370 $ 16,208 $ 202,780 Loans charged off (5,084 ) (15,804 ) (4,377 ) (2,166 ) (745 ) (1,738 ) (1,434 ) — (31,348 ) Recoveries of loans previously charged off 1,641 2,532 869 319 852 1,059 767 — 8,039 Net loans charged off (3,443 ) (13,272 ) (3,508 ) (1,847 ) 107 (679 ) (667 ) — (23,309 ) Provision for loan losses (1) (3,042 ) 13,982 6,577 1,770 (1,580 ) 879 (737 ) (7,843 ) 10,006 Balance at September 30, 2014 $ 49,174 $ 51,040 $ 31,291 $ 33,005 $ 11,176 $ 3,460 $ 1,966 $ 8,365 $ 189,477 (1) The provision for loan losses excluded a $291,000 and $472,000 increase, respectively, in the reserve for unfunded lending commitments for the three and nine months ended September 30, 2015 and a $126,000 and $ 506,000 decrease, respectively, in the reserve for unfunded lending commitments for the three and nine months ended September 30, 2014 . The total provision for credit losses, comprised of allocations for both funded and unfunded loans, was $1.0 million and negative $500,000 , respectively, for the three and nine months ended September 30, 2015 and $3.5 million and $9.5 million , respectively, for the three and nine months ended September 30, 2014 . The following table presents loans, net of unearned income and their related allowance for loan losses, by portfolio segment: Real Estate - Commercial Mortgage Commercial - Industrial, Financial and Agricultural Real Estate - Home Equity Real Estate - Residential Mortgage Real Estate - Construction Consumer Leasing and other and overdrafts Unallocated (1) Total (in thousands) Allowance for loan losses at September 30, 2015: Measured for impairment under FASB ASC Subtopic 450-20 $ 38,490 $ 36,002 $ 14,867 $ 7,921 $ 5,119 $ 2,535 $ 1,662 $ 11,547 $ 118,143 Evaluated for impairment under FASB ASC Section 310-10-35 13,197 12,721 7,183 13,423 2,450 19 — N/A 48,993 $ 51,687 $ 48,723 $ 22,050 $ 21,344 $ 7,569 $ 2,554 $ 1,662 $ 11,547 $ 167,136 Loans, net of unearned income at September 30, 2015: Measured for impairment under FASB ASC Subtopic 450-20 $ 5,273,819 $ 3,885,956 $ 1,679,471 $ 1,330,778 $ 750,629 $ 271,667 $ 149,530 N/A $ 13,341,850 Evaluated for impairment under FASB ASC Section 310-10-35 66,109 43,952 14,178 51,307 18,936 29 — N/A 194,511 $ 5,339,928 $ 3,929,908 $ 1,693,649 $ 1,382,085 $ 769,565 $ 271,696 $ 149,530 N/A $ 13,536,361 Allowance for loan losses at September 30, 2014: Measured for impairment under FASB ASC Subtopic 450-20 $ 32,951 $ 39,098 $ 21,666 $ 11,503 $ 6,009 $ 3,439 $ 1,966 $ 8,365 $ 124,997 Evaluated for impairment under FASB ASC Section 310-10-35 16,223 11,942 9,625 21,502 5,167 21 — N/A 64,480 $ 49,174 $ 51,040 $ 31,291 $ 33,005 $ 11,176 $ 3,460 $ 1,966 $ 8,365 $ 189,477 Loans, net of unearned income at September 30, 2014: Measured for impairment under FASB ASC Subtopic 450-20 $ 5,095,263 $ 3,655,162 $ 1,719,049 $ 1,319,333 $ 658,822 $ 278,196 $ 111,148 N/A $ 12,836,973 Evaluated for impairment under FASB ASC Section 310-10-35 61,716 36,100 13,987 52,700 28,906 23 — N/A 193,432 $ 5,156,979 $ 3,691,262 $ 1,733,036 $ 1,372,033 $ 687,728 $ 278,219 $ 111,148 N/A $ 13,030,405 (1) The unallocated allowance, which was approximately 7% and 4% of the total allowance for credit losses as of both September 30, 2015 and September 30, 2014 , was, in the opinion of management, reasonable and appropriate given that the estimates used in the allocation process are inherently imprecise. N/A Not applicable. Impaired Loans A loan is considered to be impaired if it is probable that all amounts will not be collected according to the contractual terms of the loan agreement. Impaired loans consist of all loans on non-accrual status and accruing troubled debt restructurings ("TDRs"). An allowance for loan losses is established for an impaired loan if its carrying value exceeds its estimated fair value. Impaired loans to borrowers with total outstanding commitments greater than or equal to $1.0 million are evaluated individually for impairment. Impaired loans to borrowers with total outstanding commitments less than $1.0 million are pooled and measured for impairment collectively. Based on an evaluation of all relevant credit quality factors, the Corporation recorded a $500,000 negative provision for credit losses during the nine months ended September 30, 2015, compared to a $9.5 million provision for credit losses for the same period in 2014. The $10.0 million decrease in the provision for credit losses was driven by improvement in all credit quality measures, particularly net charge-off levels, across all loan portfolio segments. All loans individually evaluated for impairment under FASB ASC Section 310-10-35 are measured for losses on a quarterly basis. As of September 30, 2015 and December 31, 2014 , substantially all of the Corporation’s individually evaluated impaired loans with total outstanding balances greater than or equal to $1.0 million were measured based on the estimated fair value of each loan’s collateral. Collateral could be in the form of real estate, in the case of impaired commercial mortgages and construction loans, or business assets, such as accounts receivable or inventory, in the case of commercial and industrial loans. Commercial and industrial loans may also be secured by real property. As of September 30, 2015 and 2014 , approximately 77% of impaired loans with principal balances greater than or equal to $1.0 million , whose primary collateral is real estate, were measured at estimated fair value using state certified third-party appraisals that had been updated within the preceding 12 months. When updated appraisals are not obtained for loans evaluated for impairment under FASB ASC Section 310-10-35 that are secured by real estate, fair values are estimated based on the original appraisal values, as long as the original appraisal indicated an acceptable loan-to-value position and, in the opinion of the Corporation's internal loan evaluation staff, there has not been a significant deterioration in the collateral value since the original appraisal was performed. Original appraisals are typically used only when the estimated collateral value, as adjusted for the age of the appraisal, results in a current loan-to-value ratio that is lower than the Corporation's loan-to-value requirements for new loans, generally less than 70% . The following table presents total impaired loans by class segment: September 30, 2015 December 31, 2014 Unpaid Principal Balance Recorded Investment Related Allowance Unpaid Principal Balance Recorded Investment Related Allowance (in thousands) With no related allowance recorded: Real estate - commercial mortgage $ 31,961 $ 26,075 $ — $ 25,802 $ 23,236 $ — Commercial - secured 22,097 17,661 — 17,599 14,582 — Commercial - unsecured 86 86 — — — — Real estate - home equity — — — — — — Real estate - residential mortgage 6,607 6,201 — 4,873 4,873 — Construction - commercial residential 13,353 10,417 — 18,041 14,801 — Construction - commercial 1,295 1,143 — 1,707 1,581 — 75,399 61,583 68,022 59,073 With a related allowance recorded: Real estate - commercial mortgage 48,734 40,034 13,197 49,619 40,023 16,715 Commercial - secured 29,415 23,533 11,789 24,824 19,335 12,165 Commercial - unsecured 2,832 2,672 932 1,241 1,089 865 Real estate - home equity 18,854 14,178 7,183 19,392 13,458 9,224 Real estate - residential mortgage 54,604 45,106 13,423 56,607 46,478 18,592 Construction - commercial residential 9,613 6,019 1,985 14,007 7,903 2,675 Construction - commercial 1,223 1,077 363 1,501 1,023 459 Construction - other 452 280 102 452 281 137 Consumer - direct 14 14 10 19 19 17 Consumer - indirect 15 15 9 20 19 18 165,756 132,928 48,993 167,682 129,628 60,867 Total $ 241,155 $ 194,511 $ 48,993 $ 235,704 $ 188,701 $ 60,867 As of September 30, 2015 and December 31, 2014 , there were $61.6 million and $59.1 million , respectively, of impaired loans that did not have a related allowance for loan loss. The estimated fair values of the collateral securing these loans exceeded their carrying amount, or they were previously charged down to realizable collateral values. Accordingly, no specific valuation allowance was considered to be necessary. The following table presents average impaired loans by class segment: Three months ended September 30 Nine months ended September 30 2015 2014 2015 2014 Average Interest Average Interest Average Interest Average Interest (in thousands) With no related allowance recorded: Real estate - commercial mortgage $ 25,216 $ 68 $ 23,056 $ 78 $ 26,033 $ 246 $ 23,524 244 Commercial - secured 17,609 28 18,903 29 16,142 74 20,014 98 Commercial - unsecured 43 — — — 22 — — — Real estate - home equity — — 150 — — — 225 1 Real estate - residential mortgage 6,212 34 1,236 7 5,539 94 697 13 Construction - commercial residential 10,558 28 14,881 51 12,390 124 16,052 173 Construction - commercial 1,150 — 1,060 — 1,144 — 1,514 — 60,788 158 59,286 165 61,270 538 62,026 529 With a related allowance recorded: Real estate - commercial mortgage 40,572 110 38,469 130 40,116 368 37,794 394 Commercial - secured 22,386 36 19,764 30 23,668 111 21,404 101 Commercial - unsecured 2,788 1 850 1 1,981 4 847 3 Real estate - home equity 13,728 37 14,116 30 13,417 101 14,106 78 Real estate - residential mortgage 46,039 254 51,283 298 46,406 797 51,257 894 Construction - commercial residential 5,746 15 11,189 38 6,496 64 10,480 100 Construction - commercial 1,210 — 942 — 1,005 — 567 — Construction - other 281 — 281 — 281 — 414 — Consumer - direct 15 — 18 — 18 — 15 — Consumer - indirect 15 — 6 — 17 — 4 — 132,780 453 136,918 527 133,405 1,445 136,888 1,570 Total $ 193,568 $ 611 $ 196,204 $ 692 $ 194,675 $ 1,983 $ 198,914 2,099 (1) All impaired loans, excluding accruing TDRs, were non-accrual loans. Interest income recognized for the three and nine months ended September 30, 2015 and 2014 represents amounts earned on accruing TDRs. Credit Quality Indicators and Non-performing Assets The following table presents internal credit risk ratings for real estate - commercial mortgages, commercial - secured loans, commercial - unsecured loans, construction - commercial residential loans and construction - commercial loans: Pass Special Mention Substandard or Lower Total September 30, 2015 December 31, 2014 September 30, 2015 December 31, 2014 September 30, 2015 December 31, 2014 September 30, 2015 December 31, 2014 (dollars in thousands) Real estate - commercial mortgage $ 5,028,655 $ 4,899,016 $ 132,823 $ 127,302 $ 178,450 $ 170,837 $ 5,339,928 $ 5,197,155 Commercial - secured 3,579,389 3,333,486 97,617 120,584 105,820 110,544 3,782,826 3,564,614 Commercial - unsecured 138,709 146,680 3,568 7,463 4,805 6,810 147,082 160,953 Total commercial - industrial, financial and agricultural 3,718,098 3,480,166 101,185 128,047 110,625 117,354 3,929,908 3,725,567 Construction - commercial residential 144,329 136,109 16,763 27,495 29,429 40,066 190,521 203,670 Construction - commercial 514,969 409,631 1,693 12,202 5,204 5,586 521,866 427,419 Total construction (excluding Construction - other) 659,298 545,740 18,456 39,697 34,633 45,652 712,387 631,089 $ 9,406,051 $ 8,924,922 $ 252,464 $ 295,046 $ 323,708 $ 333,843 $ 9,982,223 $ 9,553,811 % of Total 94.2 % 93.4 % 2.5 % 3.1 % 3.3 % 3.5 % 100.0 % 100.0 % The following is a summary of the Corporation's internal risk rating categories: • Pass : These loans do not currently pose undue credit risk and can range from the highest to average quality, depending on the degree of potential risk. • Special Mention : These loans constitute an undue and unwarranted credit risk, but not to a point of justifying a classification of substandard. Loans in this category are currently acceptable, but are nevertheless potentially weak. • Substandard or Lower : These loans are inadequately protected by current sound worth and paying capacity of the borrower. There exists a well-defined weakness or weaknesses that jeopardize the normal repayment of the debt. The risk rating process allows management to identify riskier credits in a timely manner and to allocate resources to managing troubled accounts. The Corporation believes that internal risk ratings are the most relevant credit quality indicator for the class segments presented above. The migration of loans through the various internal risk rating categories is a significant component of the allowance for credit loss methodology, which bases the probability of default on this migration. Assigning risk ratings involves judgment. Risk ratings are initially assigned to loans by loan officers and are reviewed on a regular basis by credit administration staff. The Corporation's loan review officers provide a separate assessment of risk rating accuracy. Ratings may be changed based on the ongoing monitoring procedures performed by loan officers or credit administration staff, or if specific loan review activities identify a deterioration or an improvement in the loan. The Corporation does not assign internal risk ratings to smaller balance, homogeneous loans, such as home equity, residential mortgage, consumer, lease receivables and construction loans to individuals secured by residential real estate. For these loans, the most relevant credit quality indicator is delinquency status. The migration of loans through the various delinquency status categories is a significant component of the allowance for credit losses methodology for those loans, which bases the probability of default on this migration. The following table presents a summary of delinquency and non-performing status for home equity, real estate - residential mortgages, construction loans to individuals and consumer, leasing and other loans by class segment: Performing Delinquent (1) Non-performing (2) Total September 30, 2015 December 31, 2014 September 30, 2015 December 31, 2014 September 30, 2015 December 31, 2014 September 30, 2015 December 31, 2014 (dollars in thousands) Real estate - home equity $ 1,671,473 $ 1,711,017 $ 9,069 $ 10,931 $ 13,107 $ 14,740 $ 1,693,649 $ 1,736,688 Real estate - residential mortgage 1,336,877 1,321,139 17,501 26,934 27,707 28,995 1,382,085 1,377,068 Construction - other 56,482 59,180 — — 696 332 57,178 59,512 Consumer - direct 98,576 104,018 2,697 2,891 1,961 2,414 103,234 109,323 Consumer - indirect 166,040 153,358 2,304 2,574 118 176 168,462 156,108 Total consumer 264,616 257,376 5,001 5,465 2,079 2,590 271,696 265,431 Leasing and other and overdrafts 148,980 118,550 464 523 86 133 149,530 119,206 $ 3,478,428 $ 3,467,262 $ 32,035 $ 43,853 $ 43,675 $ 46,790 $ 3,554,138 $ 3,557,905 % of Total 97.9 % 97.5 % 0.9 % 1.2 % 1.2 % 1.3 % 100.0 % 100.0 % (1) Includes all accruing loans 31 days to 89 days past due. (2) Includes all accruing loans 90 days or more past due and all non-accrual loans. The following table presents non-performing assets: September 30, December 31, (in thousands) Non-accrual loans $ 132,154 $ 121,080 Accruing loans 90 days or more past due 12,867 17,402 Total non-performing loans 145,021 138,482 Other real estate owned (OREO) 10,561 12,022 Total non-performing assets $ 155,582 $ 150,504 The following table presents TDRs, by class segment: September 30, December 31, (in thousands) Real-estate - residential mortgage $ 29,330 $ 31,308 Real-estate - commercial mortgage 17,282 18,822 Commercial - secured 7,259 5,170 Construction - commercial residential 4,363 9,241 Real estate - home equity 3,954 2,975 Commercial - unsecured 140 67 Consumer - indirect 15 19 Consumer - direct 14 19 Total accruing TDRs 62,357 67,621 Non-accrual TDRs (1) 27,618 24,616 Total TDRs $ 89,975 $ 92,237 (1) Included within non-accrual loans in the preceding table detailing non-performing assets. As of September 30, 2015 and December 31, 2014 , there were $5.3 million and $3.9 million , respectively, of commitments to lend additional funds to borrowers whose loans were modified under TDRs. The following table presents TDRs, by class segment as of September 30, 2015 and 2014 , that were modified during the three and nine months ended September 30, 2015 and 2014 : Three months ended September 30 Nine months ended September 30 2015 2014 2015 2014 Number of Loans Recorded Investment Number of Loans Recorded Investment Number of Loans Recorded Investment Number of Loans Recorded Investment (dollars in thousands) Commercial - secured 3 $ 1,380 3 $ 1,214 14 $ 9,203 4 $ 1,357 Real estate - home equity 14 562 6 764 39 1,793 26 1,627 Real estate - residential mortgage 2 229 3 256 10 1,295 18 2,092 Real estate - commercial mortgage 2 188 1 391 6 2,815 10 10,195 Construction - commercial residential — — — — 1 889 2 1,914 Commercial - unsecured — — — — 1 42 — — Consumer - indirect — — — — 1 13 4 7 Consumer - direct — — — — — — 6 8 Total 21 $ 2,359 13 $ 2,625 72 $ 16,050 70 $ 17,200 The following table presents TDRs, by class segment, as of September 30, 2015 and 2014 , that were modified within the previous 12 months and had a post-modification payment default during the nine months ended September 30, 2015 and 2014 . The Corporation defines a payment default as a single missed payment. 2015 2014 Number of Loans Recorded Investment Number of Loans Recorded Investment (dollars in thousands) Commercial - secured 6 $ 3,855 3 $ 415 Real estate - residential mortgage 4 500 8 1,147 Real estate - home equity 9 459 5 724 Real estate - commercial mortgage 2 233 1 35 Construction - commercial residential — — 3 2,509 Total 21 $ 5,047 20 $ 4,830 The following table presents past due status and non-accrual loans by portfolio segment and class segment: September 30, 2015 31-59 Days Past Due 60-89 Days Past Due ≥ 90 Days Past Due and Accruing Non- accrual Total ≥ 90 Days Total Past Due Current Total (in thousands) Real estate - commercial mortgage $ 7,322 $ 1,169 $ 194 $ 48,827 $ 49,021 $ 57,512 $ 5,282,416 $ 5,339,928 Commercial - secured 6,909 4,536 1,414 33,935 35,349 46,794 3,736,032 3,782,826 Commercial - unsecured 2,380 15 65 2,618 2,683 5,078 142,004 147,082 Total commercial - industrial, financial and agricultural 9,289 4,551 1,479 36,553 38,032 51,872 3,878,036 3,929,908 Real estate - home equity 6,312 2,757 2,883 10,224 13,107 22,176 1,671,473 1,693,649 Real estate - residential mortgage 11,499 6,002 5,730 21,977 27,707 45,208 1,336,877 1,382,085 Construction - commercial residential 1,832 231 — 12,073 12,073 14,136 176,385 190,521 Construction - commercial 265 — — 2,220 2,220 2,485 519,381 521,866 Construction - other — — 416 280 696 696 56,482 57,178 Total real estate - construction 2,097 231 416 14,573 14,989 17,317 752,248 769,565 Consumer - direct 1,398 1,299 1,961 — 1,961 4,658 98,576 103,234 Consumer - indirect 1,962 342 118 — 118 2,422 166,040 168,462 Total consumer 3,360 1,641 2,079 — 2,079 7,080 264,616 271,696 Leasing and other and overdrafts 449 15 86 — 86 550 148,980 149,530 Total $ 40,328 $ 16,366 $ 12,867 $ 132,154 $ 145,021 $ 201,715 $ 13,334,646 $ 13,536,361 December 31, 2014 31-59 Days Past Due 60-89 Days Past Due ≥ 90 Days Past Due and Accruing Non- accrual Total ≥ 90 Days Total Past Due Current Total (in thousands) Real estate - commercial mortgage $ 14,399 $ 3,677 $ 800 $ 44,437 $ 45,237 $ 63,313 $ 5,133,842 $ 5,197,155 Commercial - secured 4,839 958 610 28,747 29,357 35,154 3,529,460 3,564,614 Commercial - unsecured 395 65 9 1,022 1,031 1,491 159,462 160,953 Total commercial - industrial, financial and agricultural 5,234 1,023 619 29,769 30,388 36,645 3,688,922 3,725,567 Real estate - home equity 8,048 2,883 4,257 10,483 14,740 25,671 1,711,017 1,736,688 Real estate - residential mortgage 18,789 8,145 8,952 20,043 28,995 55,929 1,321,139 1,377,068 Construction - commercial residential 160 — — 13,463 13,463 13,623 190,047 203,670 Construction - commercial — — — 2,604 2,604 2,604 424,815 427,419 Construction - other — — 51 281 332 332 59,180 59,512 Total real estate - construction 160 — 51 16,348 16,399 16,559 674,042 690,601 Consumer - direct 2,034 857 2,414 — 2,414 5,305 104,018 109,323 Consumer - indirect 2,156 418 176 — 176 2,750 153,358 156,108 Total consumer 4,190 1,275 2,590 — 2,590 8,055 257,376 265,431 Leasing and other and overdrafts 357 166 133 — 133 656 118,550 119,206 Total $ 51,177 $ 17,169 $ 17,402 $ 121,080 $ 138,482 $ 206,828 $ 12,904,888 $ 13,111,716

Mortgage Servicing Rights

Mortgage Servicing Rights	9 Months Ended
	Sep. 30, 2015
Transfers and Servicing [Abstract]
Mortgage Servicing Rights	Mortgage Servicing Rights The following table summarizes the changes in mortgage servicing rights ("MSRs"), which are included in other assets on the consolidated balance sheets: Three months ended September 30 Nine months ended September 30 2015 2014 2015 2014 (in thousands) Amortized cost: Balance at beginning of period $ 41,598 $ 42,586 $ 42,148 $ 42,452 Originations of mortgage servicing rights 1,463 1,456 4,976 3,807 Amortization (1,829 ) (1,664 ) (5,892 ) (3,881 ) Balance at end of period $ 41,232 $ 42,378 $ 41,232 $ 42,378 MSRs represent the economic value of existing contractual rights to service mortgage loans that have been sold. Accordingly, actual and expected prepayments of the underlying mortgage loans can impact the value of MSRs. The Corporation accounts for MSRs at the lower of amortized cost or fair value. The fair value of MSRs is estimated by discounting the estimated cash flows from servicing income, net of expense, over the expected life of the underlying loans at a discount rate commensurate with the risk associated with these assets. Expected life is based on the contractual terms of the loans, as adjusted for prepayment projections. No valuation allowance was necessary as of September 30, 2015 or 2014. As of September 30, 2015 , the estimated fair value of MSRs was $43.8 million , which exceeded their book value.

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	Stock-Based Compensation The Corporation grants equity awards to employees, consisting of stock options, restricted stock, RSUs and PSUs under its Amended and Restated Equity and Cash Incentive Compensation Plan ("Employee Equity Plan"). In addition, employees may purchase stock under the Corporation’s Employee Stock Purchase Plan. The fair value of equity awards granted to employees is recognized as compensation expense over the period during which employees are required to provide service in exchange for such awards. Compensation expense for PSUs is also recognized over the period during which employees are required to provide service in exchange for such awards, however, compensation expense may vary based on the expectations for actual performance relative to defined performance measures. The Corporation also grants equity awards to non-employee members of its board of directors under the 2011 Directors’ Equity Participation Plan ("Directors’ Plan"). Under the Directors’ Plan, the Corporation can grant equity awards to non-employee holding company and subsidiary bank directors in the form of stock options, restricted stock or common stock. Equity awards issued under the Employee Equity Plan are generally granted annually and become fully vested over or after a three -year vesting period. The vesting period for non-performance based awards represents the period during which employees are required to provide service in exchange for such awards. Equity awards under the Directors' Plan generally vest immediately upon grant. Certain events, as defined in the Employee Equity Plan and the Directors' Plan, result in the acceleration of the vesting of equity awards. The following table presents compensation expense and the related tax benefits for equity awards recognized in the consolidated statements of income: Three months ended September 30 Nine months ended September 30 2015 2014 2015 2014 (in thousands) Stock-based compensation expense $ 1,533 $ 1,288 $ 4,371 $ 4,310 Tax benefit (489 ) (358 ) (1,403 ) (1,067 ) Stock-based compensation expense, net of tax $ 1,044 $ 930 $ 2,968 $ 3,243 Stock option fair values are estimated through the use of the Black-Scholes valuation methodology as of the date of grant. Stock options carry terms of up to ten years. Fair values for restricted stock, RSUs and a majority of PSUs are based on the trading price of the Corporation’s stock on the date of grant and earn dividends during the vesting period, which are forfeitable if the awards do not vest. The fair value of certain PSUs are estimated through the use of the Monte Carlo valuation methodology as of the date of grant. As of September 30, 2015 , the Employee Equity Plan had 11.6 million shares reserved for future grants through 2023 , and the Directors’ Plan had approximately 396,000 shares reserved for future grants through 2021 .

Employee Benefit Plans

Employee Benefit Plans	9 Months Ended
	Sep. 30, 2015
Compensation and Retirement Disclosure [Abstract]
Employee Benefit Plans	Employee Benefit Plans The Corporation maintains a defined benefit pension plan ("Pension Plan") for certain employees, which was curtailed effective January 1, 2008 . Contributions to the Pension Plan are actuarially determined and funded annually, if required. Pension Plan assets are invested in: money markets; fixed income securities, including corporate bonds, U.S. Treasury securities and common trust funds; and equity securities, including common stocks and common stock mutual funds. The net periodic benefit cost for the Corporation’s Pension Plan consisted of the following components: Three months ended September 30 Nine months ended September 30 2015 2014 2015 2014 (in thousands) Service cost (1) $ 145 $ 92 $ 435 $ 276 Interest cost 851 853 2,553 2,559 Expected return on plan assets (752 ) (811 ) (2,256 ) (2,432 ) Net amortization and deferral 782 244 2,346 732 Net periodic benefit cost $ 1,026 $ 378 $ 3,078 $ 1,135 (1) The Pension Plan service cost recorded for the nine months ended September 30, 2015 and 2014 was related to administrative costs associated with the plan and was not due to the accrual of additional participant benefits. The Corporation currently provides medical and life insurance benefits under a postretirement benefits plan ("Postretirement Plan") to certain retired full-time employees who were employees of the Corporation prior to January 1, 1998 . Effective February 1, 2014, the Corporation amended the Postretirement Plan, making all active full-time employees ineligible for benefits under this plan. As a result of this amendment, the Corporation recorded a $1.5 million gain during the nine months ended September 30, 2014, as a reduction to salaries and employee benefits on the consolidated statements of income. The gain resulted from the recognition of the remaining prior service cost prior to the amendment date as of December 31, 2013. In addition, this amendment resulted in a $3.4 million decrease in the accumulated postretirement benefit obligation and a corresponding increase in unrecognized prior service cost credits. The net periodic cost (benefit) of the Corporation’s Postretirement Plan consisted of the following components, excluding the $1.5 million plan amendment gain in 2014: Three months ended September 30 Nine months ended September 30 2015 2014 2015 2014 (in thousands) Service cost (1) $ — $ — $ — $ 15 Interest cost 52 48 156 157 Net accretion and deferral (65 ) (84 ) (195 ) (263 ) Net periodic benefit $ (13 ) $ (36 ) $ (39 ) $ (91 ) (1) As a result of the plan amendment, additional participant benefits are not accrued under the Postretirement Plan after February 1, 2014. The Corporation recognizes the funded status of its Pension Plan and Postretirement Plan on the consolidated balance sheets and recognizes the change in that funded status through other comprehensive income.

Derivative Financial Instrument

Derivative Financial Instruments	9 Months Ended
	Sep. 30, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	Derivative Financial Instruments The Corporation manages its exposure to certain interest rate and foreign currency risks through the use of derivatives. None of the Corporation's outstanding derivative contracts are designated as hedges, and none are entered into for speculative purposes. Derivative instruments are carried at fair value, with changes in fair values recognized in earnings as components of non-interest income and non-interest expense on the consolidated statements of income. Derivative contracts create counterparty credit risk with both the Corporation's customers and with institutional derivative counterparties. The Corporation manages counterparty credit risk through its credit approval processes, monitoring procedures and obtaining adequate collateral, when the Corporation determines it is appropriate to do so and in accordance with counterparty contracts. Mortgage Banking Derivatives In connection with its mortgage banking activities, the Corporation enters into commitments to originate certain fixed rate residential mortgage loans for customers, also referred to as interest rate locks. In addition, the Corporation enters into forward commitments for the future sales or purchases of mortgage-backed securities to or from third-party counterparties to hedge the effect of changes in interest rates on the values of both the interest rate locks and mortgage loans held for sale. Forward sales commitments may also be in the form of commitments to sell individual mortgage loans at a fixed price at a future date. The amount necessary to settle each interest rate lock is based on the price that secondary market investors would pay for loans with similar characteristics, including interest rate and term, as of the date fair value is measured. Gross derivative assets and liabilities are recorded within other assets and other liabilities, respectively, on the consolidated balance sheets, and changes in fair values during the period are recorded within mortgage banking income on the consolidated statements of income. Interest Rate Swaps The Corporation enters into interest rate swaps with certain qualifying commercial loan customers to meet their interest rate risk management needs. The Corporation simultaneously enters into interest rate swaps with dealer counterparties, with identical notional amounts and terms. The net result of these interest rate swaps is that the customer pays a fixed rate of interest and the Corporation receives a floating rate. These interest rate swaps are derivative financial instruments that are recorded at their fair value within other assets and other liabilities on the consolidated balance sheets, with changes in fair value during the period recorded within other non-interest expense on the consolidated statements of income. Foreign Exchange Contracts The Corporation enters into foreign exchange contracts to accommodate the needs of its customers. Foreign exchange contracts are commitments to buy or sell foreign currency on a future date at a contractual price. The Corporation offsets its foreign exchange contract exposure with customers by entering into contracts with third-party correspondent financial institutions to mitigate its exposure to fluctuations in foreign currency exchange rates. The Corporation also holds certain amounts of foreign currency with international correspondent banks. The Corporation's policy limits the total net foreign currency open positions, which includes all outstanding contracts and foreign account balances, to $500,000 . Gross derivative assets and liabilities are recorded within other assets and other liabilities, respectively, on the consolidated balance sheets, with changes in fair values during the period recorded within other service charges and fees on the consolidated statements of income. The following table presents a summary of the notional amounts and fair values of derivative financial instruments: September 30, 2015 December 31, 2014 Notional Asset Notional Asset (in thousands) Interest Rate Locks with Customers Positive fair values $ 121,546 $ 2,263 $ 89,655 $ 1,391 Negative fair values 172 (2 ) 301 (6 ) Net interest rate locks with customers 2,261 1,385 Forward Commitments Positive fair values 110 — — — Negative fair values 117,389 (1,502 ) 93,802 (1,164 ) Net forward commitments (1,502 ) (1,164 ) Interest Rate Swaps with Customers Positive fair values 681,647 37,436 468,080 19,716 Negative fair values 8,000 (87 ) 25,418 (198 ) Net interest rate swaps with customers 37,349 19,518 Interest Rate Swaps with Dealer Counterparties Positive fair values 8,000 87 25,418 198 Negative fair values 681,647 (37,436 ) 468,080 (19,716 ) Net interest rate swaps with dealer counterparties (37,349 ) (19,518 ) Foreign Exchange Contracts with Customers Positive fair values 7,183 260 11,616 810 Negative fair values 7,091 (269 ) 5,250 (441 ) Net foreign exchange contracts with customers (9 ) 369 Foreign Exchange Contracts with Correspondent Banks Positive fair values 10,308 614 5,287 446 Negative fair values 8,630 (334 ) 13,572 (876 ) Net foreign exchange contracts with correspondent banks 280 (430 ) Net derivative fair value asset $ 1,030 $ 160 The following table presents a summary of the fair value gains and losses on derivative financial instruments: Three months ended September 30 Nine months ended September 30 2015 2014 2015 2014 (in thousands) Interest rate locks with customers $ 1,041 $ (1,092 ) $ 876 $ 500 Forward commitments (3,183 ) 1,374 (338 ) (1,627 ) Interest rate swaps with customers 18,266 (40 ) 17,831 10,300 Interest rate swaps with dealer counterparties (18,266 ) 40 (17,831 ) (10,300 ) Foreign exchange contracts with customers (197 ) 557 (378 ) 854 Foreign exchange contracts with correspondent banks 323 (527 ) 710 (893 ) Net fair value gains (losses) on derivative financial instruments $ (2,016 ) $ 312 $ 870 $ (1,166 )

Fair Value Option

Fair Value Option	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Fair Value Option	Fair Value Option U.S. GAAP permits entities to measure many financial instruments and certain other items at fair value and requires certain disclosures for amounts for which the fair value option is applied. The Corporation has elected to measure mortgage loans held for sale at fair value to more accurately reflect the financial results of its mortgage banking activities in its consolidated financial statements. Derivative financial instruments related to these activities are also recorded at fair value, as noted within Note 9, "Derivative Financial Instruments." The Corporation determines fair value for its mortgage loans held for sale based on the price that secondary market investors would pay for loans with similar characteristics, including interest rate and term, as of the date fair value is measured. Changes in fair values during the period are recorded as components of mortgage banking income on the consolidated statements of income. Interest income earned on mortgage loans held for sale is classified within interest income on the consolidated statements of income. The following table presents a summary of the Corporation’s mortgage loans held for sale: September 30, December 31, (in thousands) Cost $ 26,186 $ 17,080 Fair value 26,937 17,522 During the three months ended September 30, 2015 , the Corporation recorded gains related to changes in fair values of mortgage loans held for sale of $531,000 compared to losses of $472,000 for the three months ended September 30, 2014 . For the nine months ended September 30, 2015 and 2014 , the Corporation recorded gains related to changes in fair values of mortgage loans held for sale of $309,000 and $343,000 , respectively.

Balance Sheet Offsetting

Balance Sheet Offsetting	9 Months Ended
	Sep. 30, 2015
Offsetting [Abstract]
Balance Sheet Offsetting	Balance Sheet Offsetting Certain financial assets and liabilities may be eligible for offset on the consolidated balance sheets because they are subject to master netting arrangements or similar agreements. The Corporation elects to not offset assets and liabilities subject to such arrangements on the consolidated financial statements. The Corporation is a party to interest rate swap transactions with financial institution counterparties and customers, disclosed in detail within Note 9, "Derivative Financial Instruments." Under these agreements, the Corporation has the right to net-settle multiple contracts with the same counterparty in the event of default on, or termination of, any one contract. Cash collateral is posted by the party with a net liability position in accordance with contract thresholds and can be used to settle the fair value of the interest rate swap agreements in the event of default. The Corporation is also a party to foreign currency exchange contracts with financial institution counterparties, under which the Corporation has the right to net-settle multiple contracts with the same counterparty in the event of default on, or termination of, any one contract. As with interest rate swap contracts, cash collateral is posted by the party with a net liability position in accordance with contract thresholds and can be used to settle the fair value of the foreign currency exchange contracts in the event of default. For additional details, see Note 9, "Derivative Financial Instruments." The Corporation also enters into agreements with customers in which it sells securities subject to an obligation to repurchase the same or similar securities, referred to as repurchase agreements. Under these agreements, the Corporation may transfer legal control over the assets but still maintain effective control through agreements that both entitle and obligate the Corporation to repurchase the assets. Therefore, repurchase agreements are reported as secured borrowings, classified within short-term borrowings on the consolidated balance sheets, while the securities underlying the repurchase agreements remain classified with investment securities on the consolidated balance sheets. The Corporation has no intention of setting off these amounts. Therefore, these repurchase agreements are not eligible for offset. The following table presents the Corporation's financial instruments that are eligible for offset, and the effects of offsetting, on the consolidated balance sheets: Gross Amounts Gross Amounts Not Offset Recognized on the Consolidated on the Balance Sheets Consolidated Financial Cash Net Balance Sheets Instruments (1) Collateral (2) Amount (in thousands) September 30, 2015 Interest rate swap derivative assets $ 37,523 $ (87 ) $ — $ 37,436 Foreign exchange derivative assets with correspondent banks 614 (334 ) — 280 Total $ 38,137 $ (421 ) $ — $ 37,716 Interest rate swap derivative liabilities $ 37,523 $ (87 ) $ (37,436 ) $ — Foreign exchange derivative liabilities with correspondent banks 334 (334 ) 310 310 Total $ 37,857 $ (421 ) $ (37,126 ) $ 310 December 31, 2014 Interest rate swap derivative assets $ 19,914 $ (206 ) $ — $ 19,708 Foreign exchange derivative assets with correspondent banks 446 (446 ) — — Total $ 20,360 $ (652 ) $ — $ 19,708 Interest rate swap derivative liabilities $ 19,914 $ (206 ) $ (19,210 ) $ 498 Foreign exchange derivative liabilities with correspondent banks 876 (446 ) (310 ) 120 Total $ 20,790 $ (652 ) $ (19,520 ) $ 618 (1) For interest rate swap and foreign exchange derivative assets, amounts represent any derivative liability fair values that could be offset in the event of counterparty or customer default. For interest rate swap and foreign exchange derivative liabilities, amounts represent any derivative asset fair values that could be offset in the event of counterparty or customer default. (2) Amounts represent cash collateral posted on interest rate swap transactions with financial institution counterparties. Interest rate swaps with customers are collateralized by the underlying loans to those borrowers.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Commitments The Corporation is a party to financial instruments with off-balance sheet risk in the normal course of business to meet the financing needs of its customers. Those financial instruments include commitments to extend credit and letters of credit, which involve, to varying degrees, elements of credit risk and interest rate risk in excess of the amounts recognized on the Corporation’s consolidated balance sheets. Exposure to credit loss in the event of nonperformance by the other party to the financial instrument for commitments to extend credit and letters of credit is represented by the outstanding amount of those instruments. The outstanding amounts of commitments to extend credit and letters of credit as of the dates indicated were as follows: September 30, December 31, 2014 (in thousands) Commitments to extend credit $ 5,635,629 $ 4,389,064 Standby letters of credit 390,501 382,465 Commercial letters of credit 36,365 32,304 The Corporation records a reserve for unfunded lending commitments, which represents management’s estimate of losses associated with unused commitments to extend credit. See Note 5, "Loans and Allowance for Credit Losses," for additional details. Residential Lending Residential mortgages originated and sold by the Corporation consist primarily of conforming, prime loans sold to government sponsored agencies, such as the Federal National Mortgage Association ("Fannie Mae") and the Federal Home Loan Mortgage Corporation ("Freddie Mac"). The Corporation also sells a portion of prime loans to non-government sponsored agency investors. The Corporation provides customary representations and warranties to investors that specify, among other things, that the loans have been underwritten to the standards established by the investor. The Corporation may be required to repurchase a loan, or reimburse the investor for a credit loss incurred on a loan, if it is determined that the representations and warranties have not been met. Such repurchases or reimbursements generally result from an underwriting or documentation deficiency. As of September 30, 2015 and December 31, 2014 , total outstanding repurchase requests were $851,000 and $543,000 , respectively. From 2000 to 2011 , the Corporation sold loans to the Federal Home Loan Bank of Pittsburgh under its Mortgage Partnership Finance Program ("MPF Program"). No loans were sold under this program during the nine months ended September 30, 2015 or 2014. The Corporation provided a "credit enhancement" for residential mortgage loans sold under the MPF Program whereby it would assume credit losses in excess of a defined "First Loss Account," or "FLA" balance, up to specified amounts. The FLA is funded by the Federal Home Loan Bank of Pittsburgh based on a percentage of the outstanding principal balance of loans sold. As of September 30, 2015 , the unpaid principal balance of loans sold under the MPF Program was approximately $132 million . As of September 30, 2015 and December 31, 2014 , the reserve for estimated credit losses related to loans sold under the MPF Program was $1.8 million and $2.3 million , respectively. Required reserves are calculated based on delinquency status and estimated loss rates established through the Corporation's existing allowance for credit losses methodology for residential mortgage loans. As of September 30, 2015 and December 31, 2014 , the total reserve for losses on residential mortgage loans sold was $2.5 million and $3.2 million , respectively, including both reserves for credit losses under the MPF Program and reserves for representation and warranty exposures. Management believes that the reserves recorded as of September 30, 2015 are adequate. However, declines in collateral values, the identification of additional loans to be repurchased, or a deterioration in the credit quality of loans sold under the MPF Program could necessitate additional reserves, established through charges to earnings, in the future. Other Contingencies The Corporation and its subsidiaries are involved in various legal proceedings in the ordinary course of business of the Corporation. The Corporation periodically evaluates the possible impact of pending litigation matters based on, among other factors, the advice of counsel, available insurance coverage and recorded liabilities and reserves for probable legal liabilities and costs. In addition, from time to time, the Corporation is the subject of investigations or other forms of regulatory or governmental inquiry covering a range of possible issues and, in some cases, these may be part of similar reviews of the specified activities of other industry participants. These inquiries could lead to administrative, civil or criminal proceedings, and could possibly result in fines, penalties, restitution or the need to alter the Corporation’s business practices, and cause the Corporation to incur additional costs. The Corporation’s practice is to cooperate fully with regulatory and governmental investigations. Refer also to Part II. Other Information, Item 1. Legal Proceedings.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements FASB ASC Topic 820 establishes a fair value hierarchy for the inputs to valuation techniques used to measure assets and liabilities at fair value using the following three categories (from highest to lowest priority): • Level 1 – Inputs that represent quoted prices for identical instruments in active markets. • Level 2 – Inputs that represent quoted prices for similar instruments in active markets, or quoted prices for identical instruments in non-active markets. Also includes valuation techniques whose inputs are derived principally from observable market data other than quoted prices, such as interest rates or other market-corroborated means. • Level 3 – Inputs that are largely unobservable, as little or no market data exists for the instrument being valued. The Corporation has categorized all assets and liabilities measured at fair value on both a recurring and nonrecurring basis into the above three levels. The following tables present summaries of the Corporation’s assets and liabilities measured at fair value on a recurring basis and reported on the consolidated balance sheets: September 30, 2015 Level 1 Level 2 Level 3 Total (in thousands) Mortgage loans held for sale $ — $ 26,937 $ — $ 26,937 Available for sale investment securities: Equity securities 23,532 — — 23,532 U.S. Government sponsored agency securities — 48,551 — 48,551 State and municipal securities — 240,236 — 240,236 Corporate debt securities — 96,761 3,180 99,941 Collateralized mortgage obligations — 874,299 — 874,299 Mortgage-backed securities — 1,051,905 — 1,051,905 Auction rate securities — — 97,873 97,873 Total available for sale investments 23,532 2,311,752 101,053 2,436,337 Other assets 16,253 39,787 — 56,040 Total assets $ 39,785 $ 2,378,476 $ 101,053 $ 2,519,314 Other liabilities $ 15,982 $ 39,027 $ — $ 55,009 December 31, 2014 Level 1 Level 2 Level 3 Total (in thousands) Mortgage loans held for sale $ — $ 17,522 $ — $ 17,522 Available for sale investment securities: Equity securities 47,623 — — 47,623 U.S. Government securities — 200 — 200 U.S. Government sponsored agency securities — 214 — 214 State and municipal securities — 245,215 — 245,215 Corporate debt securities — 90,126 7,908 98,034 Collateralized mortgage obligations — 902,313 — 902,313 Mortgage-backed securities — 928,831 — 928,831 Auction rate securities — — 100,941 100,941 Total available for sale investments 47,623 2,166,899 108,849 2,323,371 Other assets 17,682 21,305 — 38,987 Total assets $ 65,305 $ 2,205,726 $ 108,849 $ 2,379,880 Other liabilities $ 17,737 $ 21,084 $ — $ 38,821 The valuation techniques used to measure fair value for the items in the preceding tables are as follows: • Mortgage loans held for sale – This category consists of mortgage loans held for sale that the Corporation has elected to measure at fair value. Fair values as of September 30, 2015 and December 31, 2014 were measured based on the price that secondary market investors were offering for loans with similar characteristics. See Note 10, "Fair Value Option" for details related to the Corporation’s election to measure assets and liabilities at fair value. • Available for sale investment securities – Included within this asset category are both equity and debt securities. Level 2 available for sale debt securities are valued by a third-party pricing service commonly used in the banking industry. The pricing service uses pricing models that vary based on asset class and incorporate available market information, including quoted prices of investment securities with similar characteristics. Because many fixed income securities do not trade on a daily basis, pricing models use available information, as applicable, through processes such as benchmark yield curves, benchmarking of like securities, sector groupings, and matrix pricing. Standard market inputs include: benchmark yields, reported trades, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids, offers and reference data, including market research publications. For certain security types, additional inputs may be used, or some of the standard market inputs may not be applicable. Management tests the values provided by the pricing service by obtaining securities prices from an alternative third-party source and comparing the results. This test is done for approximately 80% of the securities valued by the pricing service. Generally, differences by security in excess of 5% are researched to reconcile the difference. • Equity securities – Equity securities consist of common stocks of financial institutions ( $22.4 million at September 30, 2015 and $41.8 million at December 31, 2014 ) and other equity investments ( $1.1 million at September 30, 2015 and $5.8 million at December 31, 2014 ). These Level 1 investments are measured at fair value based on quoted prices for identical securities in active markets. • U.S. Government securities/U.S. Government sponsored agency securities/State and municipal securities/Collateralized mortgage obligations/Mortgage-backed securities – These debt securities are classified as Level 2 investments. Fair values are determined by a third-party pricing service, as detailed above. • Corporate debt securities – This category consists of subordinated debt issued by financial institutions ( $53.6 million at September 30, 2015 and $50.0 million at December 31, 2014 ), single-issuer trust preferred securities issued by financial institutions ( $41.8 million at September 30, 2015 and $42.0 million at December 31, 2014 ), pooled trust preferred securities issued by financial institutions ( $530,000 at September 30, 2015 and $4.1 million at December 31, 2014 ) and other corporate debt issued by non-financial institutions ( $4.0 million at September 30, 2015 and $1.9 million at December 31, 2014 ). Level 2 investments include the Corporation’s holdings of subordinated debt, other corporate debt issued by non-financial institutions and $39.2 million and $38.2 million of single-issuer trust preferred securities held at September 30, 2015 and December 31, 2014 , respectively. The fair values for these corporate debt securities are determined by a third-party pricing service, as detailed above. Level 3 investments include the Corporation’s investments in pooled trust preferred securities ( $530,000 at September 30, 2015 and $4.1 million at December 31, 2014 ) and certain single-issuer trust preferred securities ( $2.7 million at September 30, 2015 and $3.8 million at December 31, 2014 ). The fair values of these securities were determined based on quotes provided by third-party brokers who determined fair values based predominantly on internal valuation models which were not indicative prices or binding offers. The Corporation’s third-party pricing service cannot derive fair values for these securities primarily due to inactive markets for similar investments. Level 3 values are tested by management primarily through trend analysis, by comparing current values to those reported at the end of the preceding calendar quarter, and determining if they are reasonable based on price and spread movements for this asset class. • Auction rate securities – Due to their illiquidity, ARCs are classified as Level 3 investments and are valued through the use of an expected cash flows model prepared by a third-party valuation expert. The assumptions used in preparing the expected cash flows model include estimates for coupon rates, time to maturity and market rates of return. The most significant unobservable input to the expected cash flows model is an assumed return to market liquidity sometime within the next five years. If the assumed return to market liquidity was lengthened beyond the next five years, this would result in a decrease in the fair value of these ARCs. The Corporation believes that the trusts underlying the ARCs will self-liquidate as student loans are repaid. Level 3 values are tested by management through the performance of a trend analysis of the market price and discount rate. Changes in the price and discount rates are compared to changes in market data, including bond ratings, parity ratios, balances and delinquency levels. Other assets – Included within this category are the following: • Level 1 assets include mutual funds that are held in trust for employee deferred compensation plans ( $15.4 million at September 30, 2015 and $16.4 million at December 31, 2014 ) and the fair value of foreign currency exchange contracts ( $874,000 at September 30, 2015 and $1.3 million at December 31, 2014 ). The mutual funds and foreign exchange prices used to measure these items at fair value are based on quoted prices for identical instruments in active markets. • Level 2 assets include the fair value of mortgage banking derivatives in the form of interest rate locks and forward commitments with secondary market investors ( $2.3 million at September 30, 2015 and $1.4 million at December 31, 2014 ) and the fair value of interest rate swaps ( $37.5 million at September 30, 2015 and $19.9 million at December 31, 2014 ). The fair values of the Corporation’s interest rate locks, forward commitments and interest rate swaps represent the amounts that would be required to settle the derivative financial instruments at the balance sheet date. See Note 9, "Derivative Financial Instruments," for additional information. • Other liabilities – Included within this category are the following: • Level 1 liabilities include employee deferred compensation liabilities which represent amounts due to employees under deferred compensation plans ( $15.4 million at September 30, 2015 and $16.4 million at December 31, 2014 ) and the fair value of foreign currency exchange contracts ( $603,000 at September 30, 2015 and $1.3 million at December 31, 2014 ). The fair value of these liabilities are determined in the same manner as the related assets, as described under the heading "Other assets" above. • Level 2 liabilities include the fair value of mortgage banking derivatives in the form of interest rate locks and forward commitments with secondary market investors ( $1.5 million at September 30, 2015 and $1.2 million at December 31, 2014 ) and the fair value of interest rate swaps ( $37.5 million at September 30, 2015 and $19.9 million at December 31, 2014 ). The fair values of these liabilities are determined in the same manner as the related assets, as described under the heading "Other assets" above. The following table presents the changes in the Corporation’s available for sale investment securities measured at fair value on a recurring basis using unobservable inputs (Level 3): Three months ended September 30, 2015 Pooled Trust Single-issuer ARCs (in thousands) Balance at June 30, 2015 $ 530 $ 3,820 $ 98,606 Unrealized adjustment to fair value (1) — (203 ) (890 ) Settlements - calls — (970 ) — Discount accretion (2) — 3 157 Balance at September 30, 2015 $ 530 $ 2,650 $ 97,873 Three months ended September 30, 2014 Balance at June 30, 2014 $ 4,275 $ 3,820 $ 146,931 Realized adjustment to fair value (3) (18 ) — — Unrealized adjustment to fair value (1) 230 47 1,280 Discount accretion (2) — 2 262 Balance at September 30, 2014 $ 4,487 $ 3,869 $ 148,473 Nine months ended September 30, 2015 Pooled Trust Single-issuer ARCs (in thousands) Balance at December 31, 2014 $ 4,088 $ 3,820 $ 100,941 Sales (3,633 ) — — Unrealized adjustment to fair value (1) 190 (207 ) (978 ) Settlements - calls (117 ) (970 ) (2,446 ) Discount accretion (2) 2 7 356 Balance at September 30, 2015 $ 530 $ 2,650 $ 97,873 Nine months ended September 30, 2014 Balance at December 31, 2013 $ 5,306 $ 3,781 $ 159,274 Sales (1,394 ) — (11,912 ) Realized adjustment to fair value (3) (18 ) — — Unrealized adjustment to fair value (1) 789 83 1,528 Settlements - calls (200 ) — (1,081 ) Discount accretion (2) 4 5 664 Balance at September 30, 2014 $ 4,487 $ 3,869 $ 148,473 (1) Pooled trust preferred securities, single-issuer trust preferred securities and ARCs are classified as available for sale investment securities; as such, the unrealized adjustment to fair value was recorded as an unrealized holding gain (loss) and included as a component of available for sale investment securities on the consolidated balance sheets. (2) Included as a component of net interest income on the consolidated statements of income. (3) Realized adjustments to fair value represent credit related other-than-temporary impairment charges and gains on sales of investment securities, both included as components of investment securities gains on the consolidated statements of income. Certain financial assets are not measured at fair value on an ongoing basis, but are subject to fair value measurement in certain circumstances, such as upon their acquisition or when there is evidence of impairment. The following table presents the Corporation’s financial assets measured at fair value on a nonrecurring basis and reported on the Corporation’s consolidated balance sheets: September 30, 2015 Level 1 Level 2 Level 3 Total (in thousands) Net loans $ — $ — $ 145,518 $ 145,518 Other financial assets — — 51,794 51,794 Total assets $ — $ — $ 197,312 $ 197,312 December 31, 2014 Level 1 Level 2 Level 3 Total (in thousands) Net loans $ — $ — $ 127,834 $ 127,834 Other financial assets — — 54,170 54,170 Total assets $ — $ — $ 182,004 $ 182,004 The valuation techniques used to measure fair value for the items in the table above are as follows: • Net loans – This category consists of loans that were evaluated for impairment under FASB ASC Section 310-10-35 and have been classified as Level 3 assets. The amount shown is the balance of impaired loans, net of the related allowance for loan losses. See Note 5, "Loans and Allowance for Credit Losses," for additional details. • Other financial assets – This category includes OREO ( $10.6 million at September 30, 2015 and $12.0 million at December 31, 2014 ) and MSRs ( $41.2 million at September 30, 2015 and $42.1 million at December 31, 2014 ), both classified as Level 3 assets. Fair values for OREO were based on estimated selling prices less estimated selling costs for similar assets in active markets. MSRs are initially recorded at fair value upon the sale of residential mortgage loans to secondary market investors. MSRs are amortized as a reduction to servicing income over the estimated lives of the underlying loans. MSRs are stratified and evaluated for impairment by comparing each stratum's carrying amount to its estimated fair value. Fair values are determined at the end of each quarter through a discounted cash flows valuation performed by a third-party valuation expert. Significant inputs to the valuation included expected net servicing income, the discount rate and the expected life of the underlying loans. Expected life is based on the contractual terms of the loans, as adjusted for prepayment projections. The weighted average annual constant prepayment rate and the weighted average discount rate used in the September 30, 2015 valuation were 11.6% and 9.6% , respectively. Management tests the reasonableness of the significant inputs to the third-party valuation in comparison to market data. As required by FASB ASC Section 825-10-50, the following table details the book values and estimated fair values of the Corporation’s financial instruments as of September 30, 2015 and December 31, 2014 . In addition, a general description of the methods and assumptions used to estimate such fair values is also provided. September 30, 2015 December 31, 2014 Book Value Estimated Book Value Estimated (in thousands) FINANCIAL ASSETS Cash and due from banks $ 93,803 $ 93,803 $ 105,702 $ 105,702 Interest-bearing deposits with other banks 510,943 510,943 358,130 358,130 Federal Reserve Bank and Federal Home Loan Bank stock 68,977 68,977 64,953 64,953 Loans held for sale (1) 26,937 26,937 17,522 17,522 Available for sale investment securities (1) 2,436,337 2,436,337 2,323,371 2,323,371 Loans, net of unearned income (1) 13,536,361 13,428,016 13,111,716 13,030,543 Accrued interest receivable 42,846 42,846 41,818 41,818 Other financial assets (1) 174,835 174,835 169,764 169,764 FINANCIAL LIABILITIES Demand and savings deposits $ 11,148,667 $ 11,148,667 $ 10,296,055 $ 10,296,055 Time deposits 2,935,727 2,944,618 3,071,451 3,069,883 Short-term borrowings 431,631 431,631 329,719 329,719 Accrued interest payable 14,727 14,727 18,045 18,045 Other financial liabilities (1) 192,281 192,281 172,786 172,786 Federal Home Loan Bank advances and long-term debt 979,433 1,002,761 1,139,413 1,142,980 (1) These financial instruments, or certain financial instruments within these categories, are measured at fair value on the Corporation’s consolidated balance sheets. Descriptions of the fair value determinations for these financial instruments are disclosed above. Fair values of financial instruments are significantly affected by the assumptions used, principally the timing of future cash flows and discount rates. Because assumptions are inherently subjective in nature, the estimated fair values cannot be substantiated by comparison to independent market quotes and, in many cases, the estimated fair values could not necessarily be realized in an immediate sale or settlement of the instrument. The aggregate fair value amounts presented do not necessarily represent management’s estimate of the underlying value of the Corporation. For short-term financial instruments, defined as those with remaining maturities of 90 days or less, and excluding those recorded at fair value on the Corporation’s consolidated balance sheets, book value was considered to be a reasonable estimate of fair value. The following instruments are predominantly short-term: Assets Liabilities Cash and due from banks Demand and savings deposits Interest bearing deposits with other banks Short-term borrowings Accrued interest receivable Accrued interest payable Federal Reserve Bank and Federal Home Loan Bank stock represent restricted investments and are carried at cost on the consolidated balance sheets. Each of the Corporation’s subsidiary banks is a member of the Federal Home Loan Bank for the region encompassing the headquarters of the subsidiary bank. Memberships are maintained with the Atlanta, New York and Pittsburgh regional Federal Home Loan Banks (collectively referred to as the "FHLB"). Fair values for loans and time deposits were estimated by discounting future cash flows using the current rates at which similar loans would be made to borrowers and similar deposits would be issued to customers for the same remaining maturities. Fair values estimated in this manner do not fully incorporate an exit price approach to fair value, as defined in FASB ASC Topic 820. The fair values of FHLB advances and long-term debt were estimated by discounting the remaining contractual cash flows using a rate at which the Corporation could issue debt with similar remaining maturities as of the balance sheet date. These borrowings would be categorized within Level 2 liabilities under FASB ASC Topic 820.

Common Stock Repurchase Plans

Common Stock Repurchase Plans	9 Months Ended
	Sep. 30, 2015
Stockholders' Equity Note [Abstract]
Common Stock Repurchase Plan	In November 2014 , the Corporation entered into an accelerated share repurchase agreement ("ASR") with a third party to repurchase $100.0 million of shares of its common stock. Under the terms of the ASR, the Corporation paid $100.0 million to the third party in November 2014 and received an initial delivery of 6.5 million shares, representing 80% of the shares expected to be delivered under the ASR, based on the closing price for the Corporation’s shares on November 13, 2014. In April 2015, the third party delivered an additional 1.8 million shares of common stock pursuant to the terms of the ASR, thereby completing the $100.0 million ASR. The Corporation repurchased a total of 8.3 million shares of common stock under the ASR at an average price of $12.05 per share. In April 2015, the Corporation announced that its board of directors had approved a share repurchase program pursuant to which the Corporation was authorized to repurchase up to $50.0 million of its outstanding shares of common stock, or approximately 2.3% of its outstanding shares, through December 31, 2015. Through September 30, 2015, approximately 4.0 million shares had been repurchased under this program for a total cost of $50.0 million , or $12.57 per share, completing this program.

Long-Term Debt

Long-Term Debt	9 Months Ended
	Sep. 30, 2015
Debt Disclosure [Abstract]
Long-Term Debt	Long-Term Debt In June 2015, the Corporation issued $150.0 million of ten -year subordinated notes, which mature on November 15, 2024 and carry a fixed rate of 4.50% and an effective rate of approximately 4.69% as a result of discounts and issuance costs. Interest is paid semi-annually in May and November. The proceeds from the issuance of the subordinated notes were used to redeem $150.0 million of trust preferred securities in July 2015. The redeemed securities carried a fixed interest rate of 6.29% and an effective rate of 6.52% , and had a scheduled maturity of February 1, 2036. As a result of this transaction, the Corporation recorded a $5.6 million loss on redemption, included as a component of non-interest expense, in July 2015. The loss on redemption included $2.5 million , net of $1.3 million tax effect, that had been recorded as an other comprehensive loss at the time the trust preferred securities were issued related to a cash flow hedge. See Note 3, "Accumulated Other Comprehensive Income," for additional details.

Subsequent Event (Notes)

Subsequent Event (Notes)	9 Months Ended
	Sep. 30, 2015
Subsequent Events [Abstract]
Subsequent Event	Subsequent Event In October 2015, the Corporation announced that its board of directors had approved a share repurchase program pursuant to which the Corporation is authorized to repurchase up to $50.0 million of its outstanding shares of common stock, or approximately 2.3% of its outstanding shares, through December 31, 2016. Repurchased shares will be added to treasury stock, at cost. As permitted by securities laws and other legal requirements and subject to market conditions and other factors, purchases may be made from time to time in open market or privately negotiated transactions, including, without limitation, through accelerated share repurchase transactions. The share repurchase program may be discontinued at any time.

Basis of Presentation Basis of

Basis of Presentation Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
New Accounting Pronouncements, Policy	Recent Accounting Standards Effective January 1, 2015, the Corporation adopted the Financial Accounting Standards Board's ("FASB") Accounting Standards Codification ("ASC") Update 2014-01, "Accounting for Investments in Qualified Affordable Housing Projects." ASC Update 2014-01 provides guidance on accounting for investments made by a reporting entity in flow-through limited liability entities that manage or invest in affordable housing projects that qualify for the low income housing tax credit. The Corporation has made certain investments in partnerships that generate tax credits under various federal programs which promote investment in low and moderate income housing and local economic development. The net income tax benefit associated with these investments, which consists of the amortization of the investments net of tax benefit, and the income tax credits earned on the investments recorded in income taxes on the consolidated income statements was $2.3 million and $2.1 million for the three months ended September 30, 2015 and 2014, respectively, and $7.1 million and $7.4 million for the nine months ended September 30, 2015 and 2014, respectively. As of September 30, 2015 and December 31, 2014, the Corporation’s tax credit investments, included in other assets on the consolidated balance sheets, totaled $164.0 million and $155.6 million , respectively. The adoption of this ASC update did not have a material impact on the Corporation's consolidated financial statements for the three or nine months ended September 30, 2015 or 2014. In February 2015, the FASB issued ASC Update 2015-02, "Consolidation: Amendments to the Consolidation Analysis." ASC Update 2015-02 changes the way reporting enterprises evaluate whether: (a) they should consolidate limited partnerships and similar entities, (b) fees paid to a decision maker or service provider are variable interests in a variable interest entity ("VIE"), and (c) variable interests in a VIE held by related parties of the reporting enterprise require the reporting enterprise to consolidate the VIE. ASC Update 2015-02 is effective for public business entities' annual and interim reporting periods beginning after December 15, 2015, with earlier adoption permitted. The Corporation intends to adopt this standards update effective with its March 31, 2016 quarterly report on Form 10-Q, and does not expect the adoption of ASC Update 2015-02 to have a material impact on its consolidated financial statements. In April 2015, the FASB issued ASC Update 2015-03, "Interest - Imputation of Interest" and updated ASC Update 2015-03 with the issuance of ASC Update 2015-15, “Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements,” in August of 2015. ASC Update 2015-03 simplifies the presentation of debt issuances costs. Debt issuance costs related to a recognized debt liability will be presented on the balance sheet as a direct deduction from the debt liability, similar to the presentation of debt discounts. Under current U.S. GAAP, debt issuance costs are reported on the balance sheet as assets. The costs will continue to be amortized to interest expense using the effective interest method. ASC Update 2015-03 is effective for public business entities' annual and interim reporting periods beginning after December 15, 2015, with earlier adoption permitted. The Corporation intends to adopt this standards update effective with its March 31, 2016 quarterly report on Form 10-Q and does not expect the adoption of ASC Update 2015-03 to have a material impact on its consolidated financial statements. In April 2015, the FASB issued ASC Update 2015-05, "Customer's Accounting for Fees Paid in a Cloud Computing Arrangement." ASC Update 2015-05 provides explicit guidance to determine when a customer's fees paid in a cloud computing arrangement is for the acquisition of software licenses, services, or both. ASC Update 2015-05 is effective for public business entities' annual and interim reporting periods beginning after December 15, 2015, with earlier adoption permitted. The Corporation intends to adopt this standards update effective with its March 31, 2016 quarterly report on Form 10-Q and does not expect the adoption of ASC Update 2015-05 to have a material impact on its consolidated financial statements.

Net Income Per Share (Tables)

Net Income Per Share (Tables)	9 Months Ended
	Sep. 30, 2015
Earnings Per Share [Abstract]
Reconciliation of Weighted Average Common Shares Outstanding	A reconciliation of weighted average shares outstanding used to calculate basic net income per share and diluted net income per share follows: Three months ended September 30 Nine months ended September 30 2015 2014 2015 2014 (in thousands) Weighted average shares outstanding (basic) 174,338 186,109 176,399 187,893 Impact of common stock equivalents 1,004 846 1,029 970 Weighted average shares outstanding (diluted) 175,342 186,955 177,428 188,863

Accumulated Other Comprehensi27

Accumulated Other Comprehensive Income Accumulated Other Comprehensive Income (Tables)	9 Months Ended
	Sep. 30, 2015
Equity [Abstract]
Changes in other comprehensive income [Table Text Block]	The following table presents changes in other comprehensive income: Before-Tax Amount Tax Effect Net of Tax Amount (in thousands) Three months ended September 30, 2015 Unrealized gain on securities $ 12,088 $ (4,231 ) $ 7,857 Reclassification adjustment for securities gains included in net income (1) (1,730 ) 606 (1,124 ) Reclassification adjustment for loss on derivative financial instruments included in net income (2) 3,778 (1,322 ) 2,456 Amortization of unrealized loss on derivative financial instruments 5 (2 ) 3 Amortization of net unrecognized pension and postretirement items (3) 717 (251 ) 466 Total Other Comprehensive Income $ 14,858 $ (5,200 ) $ 9,658 Three months ended September 30, 2014 Unrealized loss on securities $ (4,629 ) $ 1,618 $ (3,011 ) Reclassification adjustment for securities gains included in net income (1) (81 ) 29 (52 ) Non-credit related unrealized gains on other-than-temporarily impaired debt securities 212 (74 ) 138 Amortization of unrealized loss on derivative financial instruments 52 (18 ) 34 Amortization of net unrecognized pension and postretirement items (3) 160 (56 ) 104 Total Other Comprehensive Loss $ (4,286 ) $ 1,499 $ (2,787 ) Nine months ended September 30, 2015 Unrealized gain on securities $ 8,987 $ (3,146 ) $ 5,841 Reclassification adjustment for securities gains included in net income (1) (8,290 ) 2,902 (5,388 ) Reclassification adjustment for loss on derivative financial instruments included in net income (2) 3,778 (1,322 ) 2,456 Non-credit related unrealized gains (losses) on other-than-temporarily impaired debt securities 192 (67 ) 125 Amortization of unrealized loss on derivative financial instruments 110 (39 ) 71 Amortization of net unrecognized pension and postretirement items (3) 2,151 (753 ) 1,398 Total Other Comprehensive Income $ 6,928 $ (2,425 ) $ 4,503 Nine months ended September 30, 2014 Unrealized gain on securities $ 36,790 $ (12,878 ) $ 23,912 Reclassification adjustment for securities gains included in net income (1) (1,193 ) 418 (775 ) Reclassification adjustment for postretirement gains included in net income (3) (1,452 ) 508 (944 ) Non-credit related unrealized gains (losses) on other-than-temporarily impaired debt securities 1,000 (350 ) 650 Amortization of unrealized loss on derivative financial instruments 157 (55 ) 102 Unrecognized pension and postretirement income 3,291 (1,147 ) 2,144 Amortization of net unrecognized pension and postretirement items (3) 469 (165 ) 304 Total Other Comprehensive Income $ 39,062 $ (13,669 ) $ 25,393 (1) Amounts reclassified out of accumulated other comprehensive income. Before-tax amounts included within "Investment securities gains, net" on the consolidated statements of income. See Note 4, "Investment Securities," for additional details. (2) Amount reclassified out of accumulated other comprehensive income. Before-tax amount included within "Loss on Redemption of Trust Preferred Securities" on the consolidated statements of income. See Note 15, "Long-Term Debt," for additional details. (3) Amounts reclassified out of accumulated other comprehensive income. Before-tax amounts included within "Salaries and employee benefits" on the consolidated statements of income. See Note 8, "Employee Benefit Plans," for additional details.
Changes in each component of accumulated other comprehensive income [Table Text Block]	The following table presents changes in each component of accumulated other comprehensive income, net of tax: Unrealized Gains (Losses) on Investment Securities Not Other-Than-Temporarily Impaired Unrealized Non-Credit Gains (Losses) on Other-Than-Temporarily Impaired Debt Securities Unrealized Effective Portions of Losses on Forward-Starting Interest Rate Swaps Unrecognized Pension and Postretirement Plan Income (Costs) Total (in thousands) Three months ended September 30, 2015 Balance at June 30, 2015 $ 830 $ 344 $ (2,478 ) $ (21,573 ) $ (22,877 ) Other comprehensive loss before reclassifications 7,857 — — — 7,857 Amounts reclassified from accumulated other comprehensive income (loss) (1,124 ) — 3 466 (655 ) Reclassification adjustment for loss on derivative financial instruments included in net income — — — 2,456 — — 2,456 Balance at September 30, 2015 $ 7,563 $ 344 $ (19 ) $ (21,107 ) $ (13,219 ) Three months ended September 30, 2014 Balance at June 30, 2014 $ (580 ) $ 1,434 $ (2,614 ) $ (7,401 ) $ (9,161 ) Other comprehensive income before reclassifications (3,011 ) 138 — — (2,873 ) Amounts reclassified from accumulated other comprehensive income (loss) (63 ) 11 34 104 86 Balance at September 30, 2014 $ (3,654 ) $ 1,583 $ (2,580 ) $ (7,297 ) $ (11,948 ) Nine months ended September 30, 2015 Balance at December 31, 2014 $ 5,980 $ 1,349 $ (2,546 ) $ (22,505 ) $ (17,722 ) Other comprehensive income before reclassifications 5,841 125 — — 5,966 Amounts reclassified from accumulated other comprehensive income (loss) (4,258 ) (1,130 ) 71 1,398 (3,919 ) Reclassification adjustment for loss on derivative financial instruments included in net income — — 2,456 — 2,456 Balance at September 30, 2015 $ 7,563 $ 344 $ (19 ) $ (21,107 ) $ (13,219 ) Nine months ended September 30, 2014 Balance at December 31, 2013 $ (27,510 ) $ 1,652 $ (2,682 ) $ (8,801 ) $ (37,341 ) Other comprehensive income before reclassifications 23,912 650 — 2,144 26,706 Amounts reclassified from accumulated other comprehensive income (loss) (56 ) (719 ) 102 (640 ) (1,313 ) Balance at September 30, 2014 $ (3,654 ) $ 1,583 $ (2,580 ) $ (7,297 ) $ (11,948 )

Investment Securities (Tables)

Investment Securities (Tables)	9 Months Ended
	Sep. 30, 2015
Investments, Debt and Equity Securities [Abstract]
Schedule of Amortized Cost and Fair Values of Investment Securities	The following table presents the amortized cost and estimated fair values of investment securities, which were all classified as available for sale: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (in thousands) September 30, 2015 Equity securities $ 16,087 $ 7,453 $ (8 ) $ 23,532 U.S. Government sponsored agency securities 48,320 231 — 48,551 State and municipal securities 234,868 5,430 (62 ) 240,236 Corporate debt securities 102,297 2,935 (5,291 ) 99,941 Collateralized mortgage obligations 879,738 5,638 (11,077 ) 874,299 Mortgage-backed securities 1,036,193 16,845 (1,133 ) 1,051,905 Auction rate securities 106,661 — (8,788 ) 97,873 $ 2,424,164 $ 38,532 $ (26,359 ) $ 2,436,337 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (in thousands) December 31, 2014 Equity securities $ 33,469 $ 14,167 $ (13 ) $ 47,623 U.S. Government securities 200 — — 200 U.S. Government sponsored agency securities 209 5 — 214 State and municipal securities 238,250 7,231 (266 ) 245,215 Corporate debt securities 99,016 5,126 (6,108 ) 98,034 Collateralized mortgage obligations 917,395 5,705 (20,787 ) 902,313 Mortgage-backed securities 914,797 16,978 (2,944 ) 928,831 Auction rate securities 108,751 — (7,810 ) 100,941 $ 2,312,087 $ 49,212 $ (37,928 ) $ 2,323,371
Schedule of Amortized Cost and Fair Values of Debt Securities by Contractual Maturities	The amortized cost and estimated fair values of debt securities as of September 30, 2015 , by contractual maturity, are shown in the following table. Actual maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. Amortized Estimated (in thousands) Due in one year or less $ 62,247 $ 63,023 Due from one year to five years 104,989 107,283 Due from five years to ten years 132,930 136,571 Due after ten years 191,980 179,724 492,146 486,601 Collateralized mortgage obligations 879,738 874,299 Mortgage-backed securities 1,036,193 1,051,905 $ 2,408,077 $ 2,412,805
Summary of Gains and Losses from Equity and Debt Securities, and Losses Recognized from Other-than-Temporary Impairment	The following table presents information related to the gross realized gains and losses on the sales of equity and debt securities: Gross Gross Other-than- Net Gains (Losses) Three months ended September 30, 2015 (in thousands) Equity securities $ 1,730 $ — $ — $ 1,730 Debt securities — — — — Total $ 1,730 $ — $ — $ 1,730 Three months ended September 30, 2014 Equity securities $ 99 $ — $ — $ 99 Debt securities — — (18 ) (18 ) Total $ 99 $ — $ (18 ) $ 81 Nine months ended September 30, 2015 Equity securities $ 5,990 $ — $ — $ 5,990 Debt securities 2,300 — — 2,300 Total $ 8,290 $ — $ — $ 8,290 Nine months ended September 30, 2014 Equity securities $ 100 $ — $ (12 ) $ 88 Debt securities 1,446 (323 ) (18 ) 1,105 Total $ 1,546 $ (323 ) $ (30 ) $ 1,193
Summary Of Other Than Temporary Impairment Charges Recorded In Statement Of Operations [Table Text Block]	The following table presents a summary of the cumulative credit related other-than-temporary impairment charges, recognized as components of earnings, for debt securities held by the Corporation at September 30, 2015 and 2014: Three months ended September 30 Nine months ended September 30 2015 2014 2015 2014 (in thousands) Balance of cumulative credit losses on debt securities, beginning of period $ (11,510 ) $ (17,214 ) $ (16,242 ) $ (20,691 ) Additions for credit losses recorded which were not previously recognized as components of earnings — (18 ) — (18 ) Reductions for securities sold during the period — — 4,730 3,472 Reductions for increases in cash flows expected to be collected that are recognized over the remaining life of the security — — 2 5 Balance of cumulative credit losses on debt securities, end of period $ (11,510 ) $ (17,232 ) $ (11,510 ) $ (17,232 )
Gross Unrealized Losses and Fair Values of Investments by Category and Length of Time in Continuous Unrealized Loss Position	The following table presents the gross unrealized losses and estimated fair values of investments, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position at September 30, 2015 : Less than 12 months 12 months or longer Total Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses (in thousands) U.S. Government sponsored agency securities $ — $ — $ — $ — $ — $ — State and municipal securities 11,892 (62 ) — — 11,892 (62 ) Corporate debt securities 7,968 (15 ) 33,718 (5,276 ) 41,686 (5,291 ) Collateralized mortgage obligations 30,723 (62 ) 493,703 (11,015 ) 524,426 (11,077 ) Mortgage-backed securities 161,097 (443 ) 67,071 (690 ) 228,168 (1,133 ) Auction rate securities — — 97,873 (8,788 ) 97,873 (8,788 ) Total debt securities 211,680 (582 ) 692,365 (25,769 ) 904,045 (26,351 ) Equity securities — — 13 (8 ) 13 (8 ) $ 211,680 $ (582 ) $ 692,378 $ (25,777 ) $ 904,058 $ (26,359 )
Summary of Amortized Cost and Fair Values of Corporate Debt Securities	The following table presents the amortized cost and estimated fair value of corporate debt securities: September 30, 2015 December 31, 2014 Amortized cost Estimated fair value Amortized cost Estimated fair value (in thousands) Single-issuer trust preferred securities $ 46,624 $ 41,787 $ 47,569 $ 42,016 Subordinated debt 51,625 53,576 47,530 50,023 Pooled trust preferred securities — 530 2,010 4,088 Corporate debt securities issued by financial institutions 98,249 95,893 97,109 96,127 Other corporate debt securities 4,048 4,048 1,907 1,907 Available for sale corporate debt securities $ 102,297 $ 99,941 $ 99,016 $ 98,034

Loans and Allowance for Credi29

Loans and Allowance for Credit Losses (Tables)	9 Months Ended
	Sep. 30, 2015
Receivables [Abstract]
Summary of Gross Loans by Type	Loans, net of unearned income are summarized as follows: September 30, December 31, 2014 (in thousands) Real-estate - commercial mortgage $ 5,339,928 $ 5,197,155 Commercial - industrial, financial and agricultural 3,929,908 3,725,567 Real-estate - home equity 1,693,649 1,736,688 Real-estate - residential mortgage 1,382,085 1,377,068 Real-estate - construction 769,565 690,601 Consumer 271,696 265,431 Leasing and other 161,911 127,562 Overdrafts 2,614 4,021 Loans, gross of unearned income 13,551,356 13,124,093 Unearned income (14,995 ) (12,377 ) Loans, net of unearned income $ 13,536,361 $ 13,111,716
Schedule of Allowance for Credit Losses	The following table presents the components of the allowance for credit losses: September 30, December 31, (in thousands) Allowance for loan losses $ 167,136 $ 184,144 Reserve for unfunded lending commitments 2,259 1,787 Allowance for credit losses $ 169,395 $ 185,931
Activity in the Allowance for Credit Losses	The following table presents the activity in the allowance for credit losses: Three months ended September 30 Nine months ended September 30 2015 2014 2015 2014 (in thousands) Balance at beginning of period $ 169,453 $ 193,442 $ 185,931 $ 204,917 Loans charged off (5,561 ) (9,604 ) (26,697 ) (31,348 ) Recoveries of loans previously charged off 4,503 3,770 10,661 8,039 Net loans charged off (1,058 ) (5,834 ) (16,036 ) (23,309 ) Provision for credit losses 1,000 3,500 (500 ) 9,500 Balance at end of period $ 169,395 $ 191,108 $ 169,395 $ 191,108 The following table presents the activity in the allowance for loan losses by portfolio segment: Real Estate - Commercial Mortgage Commercial - Industrial, Financial and Agricultural Real Estate - Home Equity Real Estate - Residential Mortgage Real Estate - Construction Consumer Leasing and other and overdrafts Unallocated Total (in thousands) Three months ended September 30, 2015 Balance at June 30, 2015 $ 50,680 $ 49,170 $ 22,506 $ 22,787 $ 7,749 $ 2,608 $ 1,615 $ 10,370 $ 167,485 Loans charged off (660 ) (1,640 ) (940 ) (1,035 ) (114 ) (650 ) (522 ) — (5,561 ) Recoveries of loans previously charged off 842 1,598 304 201 898 314 346 — 4,503 Net loans charged off 182 (42 ) (636 ) (834 ) 784 (336 ) (176 ) — (1,058 ) Provision for loan losses (1) 825 (405 ) 180 (609 ) (964 ) 282 223 1,177 709 Balance at September 30, 2015 $ 51,687 $ 48,723 $ 22,050 $ 21,344 $ 7,569 $ 2,554 $ 1,662 $ 11,547 $ 167,136 Three months ended September 30, 2014 Balance at June 30, 2014 $ 49,842 $ 49,084 $ 32,041 $ 32,744 $ 11,331 $ 3,306 $ 1,851 $ 11,486 $ 191,685 Loans charged off (1,557 ) (5,167 ) (1,492 ) (231 ) (313 ) (538 ) (306 ) — (9,604 ) Recoveries of loans previously charged off 1,167 1,013 336 95 470 448 241 — 3,770 Net loans charged off (390 ) (4,154 ) (1,156 ) (136 ) 157 (90 ) (65 ) — (5,834 ) Provision for loan losses (1) (278 ) 6,110 406 397 (312 ) 244 180 (3,121 ) 3,626 Balance at September 30, 2014 $ 49,174 $ 51,040 $ 31,291 $ 33,005 $ 11,176 $ 3,460 $ 1,966 $ 8,365 $ 189,477 Nine months ended September 30, 2015 Balance at December 31, 2014 $ 53,493 $ 51,378 $ 28,271 $ 29,072 $ 9,756 $ 3,015 $ 1,799 $ 7,360 $ 184,144 Loans charged off (3,011 ) (14,669 ) (2,578 ) (3,099 ) (201 ) (1,787 ) (1,352 ) — (26,697 ) Recoveries of loans previously charged off 1,729 3,855 744 547 2,276 923 587 — 10,661 Net loans charged off (1,282 ) (10,814 ) (1,834 ) (2,552 ) 2,075 (864 ) (765 ) — (16,036 ) Provision for loan losses (1) (524 ) 8,159 (4,387 ) (5,176 ) (4,262 ) 403 628 4,187 (972 ) Balance at September 30, 2015 $ 51,687 $ 48,723 $ 22,050 $ 21,344 $ 7,569 $ 2,554 $ 1,662 $ 11,547 $ 167,136 Nine months ended September 30, 2014 Balance at December 31, 2013 $ 55,659 $ 50,330 $ 28,222 $ 33,082 $ 12,649 $ 3,260 $ 3,370 $ 16,208 $ 202,780 Loans charged off (5,084 ) (15,804 ) (4,377 ) (2,166 ) (745 ) (1,738 ) (1,434 ) — (31,348 ) Recoveries of loans previously charged off 1,641 2,532 869 319 852 1,059 767 — 8,039 Net loans charged off (3,443 ) (13,272 ) (3,508 ) (1,847 ) 107 (679 ) (667 ) — (23,309 ) Provision for loan losses (1) (3,042 ) 13,982 6,577 1,770 (1,580 ) 879 (737 ) (7,843 ) 10,006 Balance at September 30, 2014 $ 49,174 $ 51,040 $ 31,291 $ 33,005 $ 11,176 $ 3,460 $ 1,966 $ 8,365 $ 189,477 (1) The provision for loan losses excluded a $291,000 and $472,000 increase, respectively, in the reserve for unfunded lending commitments for the three and nine months ended September 30, 2015 and a $126,000 and $ 506,000 decrease, respectively, in the reserve for unfunded lending commitments for the three and nine months ended September 30, 2014 . The total provision for credit losses, comprised of allocations for both funded and unfunded loans, was $1.0 million and negative $500,000 , respectively, for the three and nine months ended September 30, 2015 and $3.5 million and $9.5 million , respectively, for the three and nine months ended September 30, 2014 . The following table presents loans, net of unearned income and their related allowance for loan losses, by portfolio segment: Real Estate - Commercial Mortgage Commercial - Industrial, Financial and Agricultural Real Estate - Home Equity Real Estate - Residential Mortgage Real Estate - Construction Consumer Leasing and other and overdrafts Unallocated (1) Total (in thousands) Allowance for loan losses at September 30, 2015: Measured for impairment under FASB ASC Subtopic 450-20 $ 38,490 $ 36,002 $ 14,867 $ 7,921 $ 5,119 $ 2,535 $ 1,662 $ 11,547 $ 118,143 Evaluated for impairment under FASB ASC Section 310-10-35 13,197 12,721 7,183 13,423 2,450 19 — N/A 48,993 $ 51,687 $ 48,723 $ 22,050 $ 21,344 $ 7,569 $ 2,554 $ 1,662 $ 11,547 $ 167,136 Loans, net of unearned income at September 30, 2015: Measured for impairment under FASB ASC Subtopic 450-20 $ 5,273,819 $ 3,885,956 $ 1,679,471 $ 1,330,778 $ 750,629 $ 271,667 $ 149,530 N/A $ 13,341,850 Evaluated for impairment under FASB ASC Section 310-10-35 66,109 43,952 14,178 51,307 18,936 29 — N/A 194,511 $ 5,339,928 $ 3,929,908 $ 1,693,649 $ 1,382,085 $ 769,565 $ 271,696 $ 149,530 N/A $ 13,536,361 Allowance for loan losses at September 30, 2014: Measured for impairment under FASB ASC Subtopic 450-20 $ 32,951 $ 39,098 $ 21,666 $ 11,503 $ 6,009 $ 3,439 $ 1,966 $ 8,365 $ 124,997 Evaluated for impairment under FASB ASC Section 310-10-35 16,223 11,942 9,625 21,502 5,167 21 — N/A 64,480 $ 49,174 $ 51,040 $ 31,291 $ 33,005 $ 11,176 $ 3,460 $ 1,966 $ 8,365 $ 189,477 Loans, net of unearned income at September 30, 2014: Measured for impairment under FASB ASC Subtopic 450-20 $ 5,095,263 $ 3,655,162 $ 1,719,049 $ 1,319,333 $ 658,822 $ 278,196 $ 111,148 N/A $ 12,836,973 Evaluated for impairment under FASB ASC Section 310-10-35 61,716 36,100 13,987 52,700 28,906 23 — N/A 193,432 $ 5,156,979 $ 3,691,262 $ 1,733,036 $ 1,372,033 $ 687,728 $ 278,219 $ 111,148 N/A $ 13,030,405 (1) The unallocated allowance, which was approximately 7% and 4% of the total allowance for credit losses as of both September 30, 2015 and September 30, 2014 , was, in the opinion of management, reasonable and appropriate given that the estimates used in the allocation process are inherently imprecise. N/A Not applicable
Total Impaired Loans by Class Segment	The following table presents total impaired loans by class segment: September 30, 2015 December 31, 2014 Unpaid Principal Balance Recorded Investment Related Allowance Unpaid Principal Balance Recorded Investment Related Allowance (in thousands) With no related allowance recorded: Real estate - commercial mortgage $ 31,961 $ 26,075 $ — $ 25,802 $ 23,236 $ — Commercial - secured 22,097 17,661 — 17,599 14,582 — Commercial - unsecured 86 86 — — — — Real estate - home equity — — — — — — Real estate - residential mortgage 6,607 6,201 — 4,873 4,873 — Construction - commercial residential 13,353 10,417 — 18,041 14,801 — Construction - commercial 1,295 1,143 — 1,707 1,581 — 75,399 61,583 68,022 59,073 With a related allowance recorded: Real estate - commercial mortgage 48,734 40,034 13,197 49,619 40,023 16,715 Commercial - secured 29,415 23,533 11,789 24,824 19,335 12,165 Commercial - unsecured 2,832 2,672 932 1,241 1,089 865 Real estate - home equity 18,854 14,178 7,183 19,392 13,458 9,224 Real estate - residential mortgage 54,604 45,106 13,423 56,607 46,478 18,592 Construction - commercial residential 9,613 6,019 1,985 14,007 7,903 2,675 Construction - commercial 1,223 1,077 363 1,501 1,023 459 Construction - other 452 280 102 452 281 137 Consumer - direct 14 14 10 19 19 17 Consumer - indirect 15 15 9 20 19 18 165,756 132,928 48,993 167,682 129,628 60,867 Total $ 241,155 $ 194,511 $ 48,993 $ 235,704 $ 188,701 $ 60,867 As of September 30, 2015 and December 31, 2014 , there were $61.6 million and $59.1 million , respectively, of impaired loans that did not have a related allowance for loan loss. The estimated fair values of the collateral securing these loans exceeded their carrying amount, or they were previously charged down to realizable collateral values. Accordingly, no specific valuation allowance was considered to be necessary. The following table presents average impaired loans by class segment: Three months ended September 30 Nine months ended September 30 2015 2014 2015 2014 Average Interest Average Interest Average Interest Average Interest (in thousands) With no related allowance recorded: Real estate - commercial mortgage $ 25,216 $ 68 $ 23,056 $ 78 $ 26,033 $ 246 $ 23,524 244 Commercial - secured 17,609 28 18,903 29 16,142 74 20,014 98 Commercial - unsecured 43 — — — 22 — — — Real estate - home equity — — 150 — — — 225 1 Real estate - residential mortgage 6,212 34 1,236 7 5,539 94 697 13 Construction - commercial residential 10,558 28 14,881 51 12,390 124 16,052 173 Construction - commercial 1,150 — 1,060 — 1,144 — 1,514 — 60,788 158 59,286 165 61,270 538 62,026 529 With a related allowance recorded: Real estate - commercial mortgage 40,572 110 38,469 130 40,116 368 37,794 394 Commercial - secured 22,386 36 19,764 30 23,668 111 21,404 101 Commercial - unsecured 2,788 1 850 1 1,981 4 847 3 Real estate - home equity 13,728 37 14,116 30 13,417 101 14,106 78 Real estate - residential mortgage 46,039 254 51,283 298 46,406 797 51,257 894 Construction - commercial residential 5,746 15 11,189 38 6,496 64 10,480 100 Construction - commercial 1,210 — 942 — 1,005 — 567 — Construction - other 281 — 281 — 281 — 414 — Consumer - direct 15 — 18 — 18 — 15 — Consumer - indirect 15 — 6 — 17 — 4 — 132,780 453 136,918 527 133,405 1,445 136,888 1,570 Total $ 193,568 $ 611 $ 196,204 $ 692 $ 194,675 $ 1,983 $ 198,914 2,099 (1) All impaired loans, excluding accruing TDRs, were non-accrual loans. Interest income recognized for the three and nine months ended September 30, 2015 and 2014 represents amounts earned on accruing TDRs.
Financing Receivable Credit Quality Indicators	The following table presents internal credit risk ratings for real estate - commercial mortgages, commercial - secured loans, commercial - unsecured loans, construction - commercial residential loans and construction - commercial loans: Pass Special Mention Substandard or Lower Total September 30, 2015 December 31, 2014 September 30, 2015 December 31, 2014 September 30, 2015 December 31, 2014 September 30, 2015 December 31, 2014 (dollars in thousands) Real estate - commercial mortgage $ 5,028,655 $ 4,899,016 $ 132,823 $ 127,302 $ 178,450 $ 170,837 $ 5,339,928 $ 5,197,155 Commercial - secured 3,579,389 3,333,486 97,617 120,584 105,820 110,544 3,782,826 3,564,614 Commercial - unsecured 138,709 146,680 3,568 7,463 4,805 6,810 147,082 160,953 Total commercial - industrial, financial and agricultural 3,718,098 3,480,166 101,185 128,047 110,625 117,354 3,929,908 3,725,567 Construction - commercial residential 144,329 136,109 16,763 27,495 29,429 40,066 190,521 203,670 Construction - commercial 514,969 409,631 1,693 12,202 5,204 5,586 521,866 427,419 Total construction (excluding Construction - other) 659,298 545,740 18,456 39,697 34,633 45,652 712,387 631,089 $ 9,406,051 $ 8,924,922 $ 252,464 $ 295,046 $ 323,708 $ 333,843 $ 9,982,223 $ 9,553,811 % of Total 94.2 % 93.4 % 2.5 % 3.1 % 3.3 % 3.5 % 100.0 % 100.0 % The following is a summary of the Corporation's internal risk rating categories: • Pass : These loans do not currently pose undue credit risk and can range from the highest to average quality, depending on the degree of potential risk. • Special Mention : These loans constitute an undue and unwarranted credit risk, but not to a point of justifying a classification of substandard. Loans in this category are currently acceptable, but are nevertheless potentially weak. • Substandard or Lower : These loans are inadequately protected by current sound worth and paying capacity of the borrower. There exists a well-defined weakness or weaknesses that jeopardize the normal repayment of the debt. The risk rating process allows management to identify riskier credits in a timely manner and to allocate resources to managing troubled accounts. The Corporation believes that internal risk ratings are the most relevant credit quality indicator for the class segments presented above. The migration of loans through the various internal risk rating categories is a significant component of the allowance for credit loss methodology, which bases the probability of default on this migration. Assigning risk ratings involves judgment. Risk ratings are initially assigned to loans by loan officers and are reviewed on a regular basis by credit administration staff. The Corporation's loan review officers provide a separate assessment of risk rating accuracy. Ratings may be changed based on the ongoing monitoring procedures performed by loan officers or credit administration staff, or if specific loan review activities identify a deterioration or an improvement in the loan. The Corporation does not assign internal risk ratings to smaller balance, homogeneous loans, such as home equity, residential mortgage, consumer, lease receivables and construction loans to individuals secured by residential real estate. For these loans, the most relevant credit quality indicator is delinquency status. The migration of loans through the various delinquency status categories is a significant component of the allowance for credit losses methodology for those loans, which bases the probability of default on this migration. The following table presents a summary of delinquency and non-performing status for home equity, real estate - residential mortgages, construction loans to individuals and consumer, leasing and other loans by class segment: Performing Delinquent (1) Non-performing (2) Total September 30, 2015 December 31, 2014 September 30, 2015 December 31, 2014 September 30, 2015 December 31, 2014 September 30, 2015 December 31, 2014 (dollars in thousands) Real estate - home equity $ 1,671,473 $ 1,711,017 $ 9,069 $ 10,931 $ 13,107 $ 14,740 $ 1,693,649 $ 1,736,688 Real estate - residential mortgage 1,336,877 1,321,139 17,501 26,934 27,707 28,995 1,382,085 1,377,068 Construction - other 56,482 59,180 — — 696 332 57,178 59,512 Consumer - direct 98,576 104,018 2,697 2,891 1,961 2,414 103,234 109,323 Consumer - indirect 166,040 153,358 2,304 2,574 118 176 168,462 156,108 Total consumer 264,616 257,376 5,001 5,465 2,079 2,590 271,696 265,431 Leasing and other and overdrafts 148,980 118,550 464 523 86 133 149,530 119,206 $ 3,478,428 $ 3,467,262 $ 32,035 $ 43,853 $ 43,675 $ 46,790 $ 3,554,138 $ 3,557,905 % of Total 97.9 % 97.5 % 0.9 % 1.2 % 1.2 % 1.3 % 100.0 % 100.0 % (1) Includes all accruing loans 31 days to 89 days past due. (2) Includes all accruing loans 90 days or more past due and all non-accrual loans.
Non-Performing Assets	The following table presents non-performing assets: September 30, December 31, (in thousands) Non-accrual loans $ 132,154 $ 121,080 Accruing loans 90 days or more past due 12,867 17,402 Total non-performing loans 145,021 138,482 Other real estate owned (OREO) 10,561 12,022 Total non-performing assets $ 155,582 $ 150,504
Troubled Debt Restructurings on Financing Receivables	The following table presents TDRs, by class segment: September 30, December 31, (in thousands) Real-estate - residential mortgage $ 29,330 $ 31,308 Real-estate - commercial mortgage 17,282 18,822 Commercial - secured 7,259 5,170 Construction - commercial residential 4,363 9,241 Real estate - home equity 3,954 2,975 Commercial - unsecured 140 67 Consumer - indirect 15 19 Consumer - direct 14 19 Total accruing TDRs 62,357 67,621 Non-accrual TDRs (1) 27,618 24,616 Total TDRs $ 89,975 $ 92,237 (1) Included within non-accrual loans in the preceding table detailing non-performing assets
Loan Terms Modified Under Troubled Debt Restructurings	The following table presents TDRs, by class segment as of September 30, 2015 and 2014 , that were modified during the three and nine months ended September 30, 2015 and 2014 : Three months ended September 30 Nine months ended September 30 2015 2014 2015 2014 Number of Loans Recorded Investment Number of Loans Recorded Investment Number of Loans Recorded Investment Number of Loans Recorded Investment (dollars in thousands) Commercial - secured 3 $ 1,380 3 $ 1,214 14 $ 9,203 4 $ 1,357 Real estate - home equity 14 562 6 764 39 1,793 26 1,627 Real estate - residential mortgage 2 229 3 256 10 1,295 18 2,092 Real estate - commercial mortgage 2 188 1 391 6 2,815 10 10,195 Construction - commercial residential — — — — 1 889 2 1,914 Commercial - unsecured — — — — 1 42 — — Consumer - indirect — — — — 1 13 4 7 Consumer - direct — — — — — — 6 8 Total 21 $ 2,359 13 $ 2,625 72 $ 16,050 70 $ 17,200 The following table presents TDRs, by class segment, as of September 30, 2015 and 2014 , that were modified within the previous 12 months and had a post-modification payment default during the nine months ended September 30, 2015 and 2014 . The Corporation defines a payment default as a single missed payment. 2015 2014 Number of Loans Recorded Investment Number of Loans Recorded Investment (dollars in thousands) Commercial - secured 6 $ 3,855 3 $ 415 Real estate - residential mortgage 4 500 8 1,147 Real estate - home equity 9 459 5 724 Real estate - commercial mortgage 2 233 1 35 Construction - commercial residential — — 3 2,509 Total 21 $ 5,047 20 $ 4,830
Past due Loan Status and Non-Accrual Loans by Portfolio Segment	The following table presents past due status and non-accrual loans by portfolio segment and class segment: September 30, 2015 31-59 Days Past Due 60-89 Days Past Due ≥ 90 Days Past Due and Accruing Non- accrual Total ≥ 90 Days Total Past Due Current Total (in thousands) Real estate - commercial mortgage $ 7,322 $ 1,169 $ 194 $ 48,827 $ 49,021 $ 57,512 $ 5,282,416 $ 5,339,928 Commercial - secured 6,909 4,536 1,414 33,935 35,349 46,794 3,736,032 3,782,826 Commercial - unsecured 2,380 15 65 2,618 2,683 5,078 142,004 147,082 Total commercial - industrial, financial and agricultural 9,289 4,551 1,479 36,553 38,032 51,872 3,878,036 3,929,908 Real estate - home equity 6,312 2,757 2,883 10,224 13,107 22,176 1,671,473 1,693,649 Real estate - residential mortgage 11,499 6,002 5,730 21,977 27,707 45,208 1,336,877 1,382,085 Construction - commercial residential 1,832 231 — 12,073 12,073 14,136 176,385 190,521 Construction - commercial 265 — — 2,220 2,220 2,485 519,381 521,866 Construction - other — — 416 280 696 696 56,482 57,178 Total real estate - construction 2,097 231 416 14,573 14,989 17,317 752,248 769,565 Consumer - direct 1,398 1,299 1,961 — 1,961 4,658 98,576 103,234 Consumer - indirect 1,962 342 118 — 118 2,422 166,040 168,462 Total consumer 3,360 1,641 2,079 — 2,079 7,080 264,616 271,696 Leasing and other and overdrafts 449 15 86 — 86 550 148,980 149,530 Total $ 40,328 $ 16,366 $ 12,867 $ 132,154 $ 145,021 $ 201,715 $ 13,334,646 $ 13,536,361 December 31, 2014 31-59 Days Past Due 60-89 Days Past Due ≥ 90 Days Past Due and Accruing Non- accrual Total ≥ 90 Days Total Past Due Current Total (in thousands) Real estate - commercial mortgage $ 14,399 $ 3,677 $ 800 $ 44,437 $ 45,237 $ 63,313 $ 5,133,842 $ 5,197,155 Commercial - secured 4,839 958 610 28,747 29,357 35,154 3,529,460 3,564,614 Commercial - unsecured 395 65 9 1,022 1,031 1,491 159,462 160,953 Total commercial - industrial, financial and agricultural 5,234 1,023 619 29,769 30,388 36,645 3,688,922 3,725,567 Real estate - home equity 8,048 2,883 4,257 10,483 14,740 25,671 1,711,017 1,736,688 Real estate - residential mortgage 18,789 8,145 8,952 20,043 28,995 55,929 1,321,139 1,377,068 Construction - commercial residential 160 — — 13,463 13,463 13,623 190,047 203,670 Construction - commercial — — — 2,604 2,604 2,604 424,815 427,419 Construction - other — — 51 281 332 332 59,180 59,512 Total real estate - construction 160 — 51 16,348 16,399 16,559 674,042 690,601 Consumer - direct 2,034 857 2,414 — 2,414 5,305 104,018 109,323 Consumer - indirect 2,156 418 176 — 176 2,750 153,358 156,108 Total consumer 4,190 1,275 2,590 — 2,590 8,055 257,376 265,431 Leasing and other and overdrafts 357 166 133 — 133 656 118,550 119,206 Total $ 51,177 $ 17,169 $ 17,402 $ 121,080 $ 138,482 $ 206,828 $ 12,904,888 $ 13,111,716

Mortgage Servicing Rights (Tabl

Mortgage Servicing Rights (Tables)	9 Months Ended
	Sep. 30, 2015
Transfers and Servicing [Abstract]
Summary of Changes in Mortgage Servicing Rights	The following table summarizes the changes in mortgage servicing rights ("MSRs"), which are included in other assets on the consolidated balance sheets: Three months ended September 30 Nine months ended September 30 2015 2014 2015 2014 (in thousands) Amortized cost: Balance at beginning of period $ 41,598 $ 42,586 $ 42,148 $ 42,452 Originations of mortgage servicing rights 1,463 1,456 4,976 3,807 Amortization (1,829 ) (1,664 ) (5,892 ) (3,881 ) Balance at end of period $ 41,232 $ 42,378 $ 41,232 $ 42,378

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of Compensation Expense and Related Tax Benefits	The following table presents compensation expense and the related tax benefits for equity awards recognized in the consolidated statements of income: Three months ended September 30 Nine months ended September 30 2015 2014 2015 2014 (in thousands) Stock-based compensation expense $ 1,533 $ 1,288 $ 4,371 $ 4,310 Tax benefit (489 ) (358 ) (1,403 ) (1,067 ) Stock-based compensation expense, net of tax $ 1,044 $ 930 $ 2,968 $ 3,243

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	9 Months Ended
	Sep. 30, 2015
Compensation and Retirement Disclosure [Abstract]
Schedule of Defined Benefit Plans Disclosures [Table Text Block]	The net periodic benefit cost for the Corporation’s Pension Plan consisted of the following components: Three months ended September 30 Nine months ended September 30 2015 2014 2015 2014 (in thousands) Service cost (1) $ 145 $ 92 $ 435 $ 276 Interest cost 851 853 2,553 2,559 Expected return on plan assets (752 ) (811 ) (2,256 ) (2,432 ) Net amortization and deferral 782 244 2,346 732 Net periodic benefit cost $ 1,026 $ 378 $ 3,078 $ 1,135 (1) The Pension Plan service cost recorded for the nine months ended September 30, 2015 and 2014 was related to administrative costs associated with the plan and was not due to the accrual of additional participant benefits. The net periodic cost (benefit) of the Corporation’s Postretirement Plan consisted of the following components, excluding the $1.5 million plan amendment gain in 2014: Three months ended September 30 Nine months ended September 30 2015 2014 2015 2014 (in thousands) Service cost (1) $ — $ — $ — $ 15 Interest cost 52 48 156 157 Net accretion and deferral (65 ) (84 ) (195 ) (263 ) Net periodic benefit $ (13 ) $ (36 ) $ (39 ) $ (91 ) (1) As a result of the plan amendment, additional participant benefits are not accrued under the Postretirement Plan after February 1, 2014.

Derivative Financial Instrume33

Derivative Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Summary of Notional Amounts and Fair Values of Derivative Financial Instruments	The following table presents a summary of the notional amounts and fair values of derivative financial instruments: September 30, 2015 December 31, 2014 Notional Asset Notional Asset (in thousands) Interest Rate Locks with Customers Positive fair values $ 121,546 $ 2,263 $ 89,655 $ 1,391 Negative fair values 172 (2 ) 301 (6 ) Net interest rate locks with customers 2,261 1,385 Forward Commitments Positive fair values 110 — — — Negative fair values 117,389 (1,502 ) 93,802 (1,164 ) Net forward commitments (1,502 ) (1,164 ) Interest Rate Swaps with Customers Positive fair values 681,647 37,436 468,080 19,716 Negative fair values 8,000 (87 ) 25,418 (198 ) Net interest rate swaps with customers 37,349 19,518 Interest Rate Swaps with Dealer Counterparties Positive fair values 8,000 87 25,418 198 Negative fair values 681,647 (37,436 ) 468,080 (19,716 ) Net interest rate swaps with dealer counterparties (37,349 ) (19,518 ) Foreign Exchange Contracts with Customers Positive fair values 7,183 260 11,616 810 Negative fair values 7,091 (269 ) 5,250 (441 ) Net foreign exchange contracts with customers (9 ) 369 Foreign Exchange Contracts with Correspondent Banks Positive fair values 10,308 614 5,287 446 Negative fair values 8,630 (334 ) 13,572 (876 ) Net foreign exchange contracts with correspondent banks 280 (430 ) Net derivative fair value asset $ 1,030 $ 160
Summary of Fair Value Gains and Losses on Derivative Financial Instruments	The following table presents a summary of the fair value gains and losses on derivative financial instruments: Three months ended September 30 Nine months ended September 30 2015 2014 2015 2014 (in thousands) Interest rate locks with customers $ 1,041 $ (1,092 ) $ 876 $ 500 Forward commitments (3,183 ) 1,374 (338 ) (1,627 ) Interest rate swaps with customers 18,266 (40 ) 17,831 10,300 Interest rate swaps with dealer counterparties (18,266 ) 40 (17,831 ) (10,300 ) Foreign exchange contracts with customers (197 ) 557 (378 ) 854 Foreign exchange contracts with correspondent banks 323 (527 ) 710 (893 ) Net fair value gains (losses) on derivative financial instruments $ (2,016 ) $ 312 $ 870 $ (1,166 )

Fair Value Option (Tables)

Fair Value Option (Tables)	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Summary of Corporation's Mortgage Loans Held for Sale	The following table presents a summary of the Corporation’s mortgage loans held for sale: September 30, December 31, (in thousands) Cost $ 26,186 $ 17,080 Fair value 26,937 17,522

Balance Sheet Offsetting (Table

Balance Sheet Offsetting (Tables)	9 Months Ended
	Sep. 30, 2015
Offsetting [Abstract]
Balance Sheet Offsetting	The following table presents the Corporation's financial instruments that are eligible for offset, and the effects of offsetting, on the consolidated balance sheets: Gross Amounts Gross Amounts Not Offset Recognized on the Consolidated on the Balance Sheets Consolidated Financial Cash Net Balance Sheets Instruments (1) Collateral (2) Amount (in thousands) September 30, 2015 Interest rate swap derivative assets $ 37,523 $ (87 ) $ — $ 37,436 Foreign exchange derivative assets with correspondent banks 614 (334 ) — 280 Total $ 38,137 $ (421 ) $ — $ 37,716 Interest rate swap derivative liabilities $ 37,523 $ (87 ) $ (37,436 ) $ — Foreign exchange derivative liabilities with correspondent banks 334 (334 ) 310 310 Total $ 37,857 $ (421 ) $ (37,126 ) $ 310 December 31, 2014 Interest rate swap derivative assets $ 19,914 $ (206 ) $ — $ 19,708 Foreign exchange derivative assets with correspondent banks 446 (446 ) — — Total $ 20,360 $ (652 ) $ — $ 19,708 Interest rate swap derivative liabilities $ 19,914 $ (206 ) $ (19,210 ) $ 498 Foreign exchange derivative liabilities with correspondent banks 876 (446 ) (310 ) 120 Total $ 20,790 $ (652 ) $ (19,520 ) $ 618 (1) For interest rate swap and foreign exchange derivative assets, amounts represent any derivative liability fair values that could be offset in the event of counterparty or customer default. For interest rate swap and foreign exchange derivative liabilities, amounts represent any derivative asset fair values that could be offset in the event of counterparty or customer default. (2) Amounts represent cash collateral posted on interest rate swap transactions with financial institution counterparties. Interest rate swaps with customers are collateralized by the underlying loans to those borrowers.

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Summary of Outstanding Commitments to Extend Credit and Letters of Credit	The outstanding amounts of commitments to extend credit and letters of credit as of the dates indicated were as follows: September 30, December 31, 2014 (in thousands) Commitments to extend credit $ 5,635,629 $ 4,389,064 Standby letters of credit 390,501 382,465 Commercial letters of credit 36,365 32,304

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following tables present summaries of the Corporation’s assets and liabilities measured at fair value on a recurring basis and reported on the consolidated balance sheets: September 30, 2015 Level 1 Level 2 Level 3 Total (in thousands) Mortgage loans held for sale $ — $ 26,937 $ — $ 26,937 Available for sale investment securities: Equity securities 23,532 — — 23,532 U.S. Government sponsored agency securities — 48,551 — 48,551 State and municipal securities — 240,236 — 240,236 Corporate debt securities — 96,761 3,180 99,941 Collateralized mortgage obligations — 874,299 — 874,299 Mortgage-backed securities — 1,051,905 — 1,051,905 Auction rate securities — — 97,873 97,873 Total available for sale investments 23,532 2,311,752 101,053 2,436,337 Other assets 16,253 39,787 — 56,040 Total assets $ 39,785 $ 2,378,476 $ 101,053 $ 2,519,314 Other liabilities $ 15,982 $ 39,027 $ — $ 55,009 December 31, 2014 Level 1 Level 2 Level 3 Total (in thousands) Mortgage loans held for sale $ — $ 17,522 $ — $ 17,522 Available for sale investment securities: Equity securities 47,623 — — 47,623 U.S. Government securities — 200 — 200 U.S. Government sponsored agency securities — 214 — 214 State and municipal securities — 245,215 — 245,215 Corporate debt securities — 90,126 7,908 98,034 Collateralized mortgage obligations — 902,313 — 902,313 Mortgage-backed securities — 928,831 — 928,831 Auction rate securities — — 100,941 100,941 Total available for sale investments 47,623 2,166,899 108,849 2,323,371 Other assets 17,682 21,305 — 38,987 Total assets $ 65,305 $ 2,205,726 $ 108,849 $ 2,379,880 Other liabilities $ 17,737 $ 21,084 $ — $ 38,821
Schedule of Changes in Assets and Liabilities Measured at Fair Value on a Recurring Basis using Level 3 Inputs	The following table presents the changes in the Corporation’s available for sale investment securities measured at fair value on a recurring basis using unobservable inputs (Level 3): Three months ended September 30, 2015 Pooled Trust Single-issuer ARCs (in thousands) Balance at June 30, 2015 $ 530 $ 3,820 $ 98,606 Unrealized adjustment to fair value (1) — (203 ) (890 ) Settlements - calls — (970 ) — Discount accretion (2) — 3 157 Balance at September 30, 2015 $ 530 $ 2,650 $ 97,873 Three months ended September 30, 2014 Balance at June 30, 2014 $ 4,275 $ 3,820 $ 146,931 Realized adjustment to fair value (3) (18 ) — — Unrealized adjustment to fair value (1) 230 47 1,280 Discount accretion (2) — 2 262 Balance at September 30, 2014 $ 4,487 $ 3,869 $ 148,473 Nine months ended September 30, 2015 Pooled Trust Single-issuer ARCs (in thousands) Balance at December 31, 2014 $ 4,088 $ 3,820 $ 100,941 Sales (3,633 ) — — Unrealized adjustment to fair value (1) 190 (207 ) (978 ) Settlements - calls (117 ) (970 ) (2,446 ) Discount accretion (2) 2 7 356 Balance at September 30, 2015 $ 530 $ 2,650 $ 97,873 Nine months ended September 30, 2014 Balance at December 31, 2013 $ 5,306 $ 3,781 $ 159,274 Sales (1,394 ) — (11,912 ) Realized adjustment to fair value (3) (18 ) — — Unrealized adjustment to fair value (1) 789 83 1,528 Settlements - calls (200 ) — (1,081 ) Discount accretion (2) 4 5 664 Balance at September 30, 2014 $ 4,487 $ 3,869 $ 148,473 (1) Pooled trust preferred securities, single-issuer trust preferred securities and ARCs are classified as available for sale investment securities; as such, the unrealized adjustment to fair value was recorded as an unrealized holding gain (loss) and included as a component of available for sale investment securities on the consolidated balance sheets. (2) Included as a component of net interest income on the consolidated statements of income. (3) Realized adjustments to fair value represent credit related other-than-temporary impairment charges and gains on sales of investment securities, both included as components of investment securities gains on the consolidated statements of income.
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis	The following table presents the Corporation’s financial assets measured at fair value on a nonrecurring basis and reported on the Corporation’s consolidated balance sheets: September 30, 2015 Level 1 Level 2 Level 3 Total (in thousands) Net loans $ — $ — $ 145,518 $ 145,518 Other financial assets — — 51,794 51,794 Total assets $ — $ — $ 197,312 $ 197,312 December 31, 2014 Level 1 Level 2 Level 3 Total (in thousands) Net loans $ — $ — $ 127,834 $ 127,834 Other financial assets — — 54,170 54,170 Total assets $ — $ — $ 182,004 $ 182,004
Details of Book Value and Fair Value of Financial Instruments	As required by FASB ASC Section 825-10-50, the following table details the book values and estimated fair values of the Corporation’s financial instruments as of September 30, 2015 and December 31, 2014 . In addition, a general description of the methods and assumptions used to estimate such fair values is also provided. September 30, 2015 December 31, 2014 Book Value Estimated Book Value Estimated (in thousands) FINANCIAL ASSETS Cash and due from banks $ 93,803 $ 93,803 $ 105,702 $ 105,702 Interest-bearing deposits with other banks 510,943 510,943 358,130 358,130 Federal Reserve Bank and Federal Home Loan Bank stock 68,977 68,977 64,953 64,953 Loans held for sale (1) 26,937 26,937 17,522 17,522 Available for sale investment securities (1) 2,436,337 2,436,337 2,323,371 2,323,371 Loans, net of unearned income (1) 13,536,361 13,428,016 13,111,716 13,030,543 Accrued interest receivable 42,846 42,846 41,818 41,818 Other financial assets (1) 174,835 174,835 169,764 169,764 FINANCIAL LIABILITIES Demand and savings deposits $ 11,148,667 $ 11,148,667 $ 10,296,055 $ 10,296,055 Time deposits 2,935,727 2,944,618 3,071,451 3,069,883 Short-term borrowings 431,631 431,631 329,719 329,719 Accrued interest payable 14,727 14,727 18,045 18,045 Other financial liabilities (1) 192,281 192,281 172,786 172,786 Federal Home Loan Bank advances and long-term debt 979,433 1,002,761 1,139,413 1,142,980 (1) These financial instruments, or certain financial instruments within these categories, are measured at fair value on the Corporation’s consolidated balance sheets. Descriptions of the fair value determinations for these financial instruments are disclosed above.

Basis of Presentation Basis o38

Basis of Presentation Basis of Presentation (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Tax Credit Carryforward [Line Items]
Income Tax Expense (Benefit)	$ 10,328	$ 13,402	$ 36,007	$ 41,136
Other Assets
Tax Credit Carryforward [Line Items]
Investments, low income housing	164,000		164,000		$ 155,600
LIH Low Income Housing
Tax Credit Carryforward [Line Items]
Income Tax Expense (Benefit)	$ (2,300)	$ (2,100)	$ (7,100)	$ (7,400)

Net Income Per Share Reconcilia

Net Income Per Share Reconciliation of Weighted Average Common Shares Outstanding (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Weighted average shares outstanding (basic)	174,338	186,109	176,399	187,893
Impact of common stock equivalents	1,004	846	1,029	970
Weighted average shares outstanding (diluted)	175,342	186,955	177,428	188,863

Net Income Per Share Narrative

Net Income Per Share Narrative (Details) - shares shares in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	1.5	2.5	1.8	2.9

Accumulated Other Comprehensi41

Accumulated Other Comprehensive Income Changes in Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Equity [Abstract]
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax	$ 12,088	$ (4,629)	$ 8,987	$ 36,790
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax	(4,231)	1,618	(3,146)	(12,878)
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax	7,857	(3,011)	5,841	23,912
Other Comprehensive Income (Loss), Reclassification Adjustment for Sale of Securities Included in Net Income, before Tax	(1,730)	(81)	(8,290)	(1,193)
Other Comprehensive Income (Loss), Reclassification Adjustment for Sale of Securities Included in Net Income, Tax	606	29	2,902	418
Other Comprehensive Income (Loss), Reclassification Adjustment for Sale of Securities Included in Net Income, Net of Tax	(1,124)	(52)	(5,388)	(775)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	3,778		3,778
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax	(1,322)		(1,322)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax	2,456	0	2,456	0
Other than Temporary Impairment Losses, Investments, Portion in Other Comprehensive Income (Loss), before Tax, Including Portion Attributable to Noncontrolling Interest		212	192	1,000
Other than Temporary Impairment Losses, Investments, Portion in Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent		(74)	(67)	(350)
Other than Temporary Impairment Losses, Investments, Portion in Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	0	138	125	650
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	5	52	110	157
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax	(2)	(18)	(39)	(55)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	3	34	71	102
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Net Prior Service Cost (Credit) Arising During Period, before Tax				3,291
Other Comprehensive Income (Loss), Amortization, Pension and Other Postretirement Benefit Plans, Net Prior Service Cost (Credit) Recognized in Net Periodic Benefit Cost, before Tax	717	160	2,151	469
Other Comprehensive Income (Loss), Amortization, Pension and Other Postretirement Benefit Plans, Net Prior Service Cost Recognized in Net Periodic Pension Cost, Tax Effect	(251)	(56)	(753)	(165)
Other Comprehensive Income (Loss), Amortization, Pension and Other Postretirement Benefit Plans, Net Prior Service Cost Recognized in Net Periodic Pension Cost, Net of Tax	466	104	1,398	304
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Gain (Loss), before Tax				(1,452)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Gain (Loss), Tax				508
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net (Gain) Loss, Net of Tax	0	0	0	(944)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, Tax				(1,147)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, Net of Tax	0	0	0	2,144
Other Comprehensive Income (Loss), before Tax	14,858	(4,286)	6,928	39,062
Other Comprehensive Income (Loss), Tax	(5,200)	1,499	(2,425)	(13,669)
Other Comprehensive Income (Loss)	$ 9,658	$ (2,787)	$ 4,503	$ 25,393

Accumulated Other Comprehensi42

Accumulated Other Comprehensive Income Components of Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance	$ (22,877)	$ (9,161)	$ (17,722)	$ (37,341)
Other comprehensive loss before reclassifications	7,857	(2,873)	5,966	26,706
Reclassification adjustment from AOCI	(655)	86	(3,919)	(1,313)
Ending Balance	(13,219)	(11,948)	(13,219)	(11,948)
Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income [Roll Forward]
Reclassification adjustment from AOCI	(2,456)		2,456
Unrealized Gains on Investment Securities Not Other-Than-Temporarily Impaired [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance	830	(580)	5,980	(27,510)
Other comprehensive loss before reclassifications	7,857	(3,011)	5,841	23,912
Reclassification adjustment from AOCI	(1,124)	(63)	(4,258)	(56)
Ending Balance	7,563	(3,654)	7,563	(3,654)
Unrealized Gains on Investment Securities Not Other-Than-Temporarily Impaired [Member] | Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income [Roll Forward]
Reclassification adjustment from AOCI	0		0
Unrealized Non-Credit Losses on Other-Than-Temporarily Impaired Debt Securities [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance	344	1,434	1,349	1,652
Other comprehensive loss before reclassifications	0	138	125	650
Reclassification adjustment from AOCI	0	11	(1,130)	(719)
Ending Balance	344	1,583	344	1,583
Unrealized Non-Credit Losses on Other-Than-Temporarily Impaired Debt Securities [Member] | Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income [Roll Forward]
Reclassification adjustment from AOCI	0		0
Unrealized Effective Portions of Losses on Forward-Starting Interest Rate Swaps [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance	(2,478)	(2,614)	(2,546)	(2,682)
Other comprehensive loss before reclassifications	0	0	0	0
Reclassification adjustment from AOCI	3	34	71	102
Ending Balance	(19)	(2,580)	(19)	(2,580)
Unrealized Effective Portions of Losses on Forward-Starting Interest Rate Swaps [Member] | Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income [Roll Forward]
Reclassification adjustment from AOCI	(2,456)		2,456
Unrecognized Pension and Postretirement Plan Income (Costs) [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance	(21,573)	(7,401)	(22,505)	(8,801)
Other comprehensive loss before reclassifications	0	0	0	2,144
Reclassification adjustment from AOCI	466	104	1,398	(640)
Ending Balance	(21,107)	$ (7,297)	(21,107)	$ (7,297)
Unrecognized Pension and Postretirement Plan Income (Costs) [Member] | Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income [Roll Forward]
Reclassification adjustment from AOCI	$ 0		$ 0

Investment Securities Schedule

Investment Securities Schedule of Amortized Cost and Fair Values of Investment Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Schedule of Investments [Line Items]
Amortized Cost	$ 2,424,164	$ 2,312,087
Gross Unrealized Gains	38,532	49,212
Gross Unrealized Losses	(26,359)	(37,928)
Estimated Fair Value	2,436,337	2,323,371
Equity Securities [Member]
Schedule of Investments [Line Items]
Amortized Cost	16,087	33,469
Gross Unrealized Gains	7,453	14,167
Gross Unrealized Losses	(8)	(13)
Estimated Fair Value	23,532	47,623
U.S. Government Securities [Member]
Schedule of Investments [Line Items]
Amortized Cost		200
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Estimated Fair Value		200
U.S. Government-Sponsored Agency Securities [Member]
Schedule of Investments [Line Items]
Amortized Cost	48,320	209
Gross Unrealized Gains	231	5
Gross Unrealized Losses	0	0
Estimated Fair Value	48,551	214
State and Municipal Securities [Member]
Schedule of Investments [Line Items]
Amortized Cost	234,868	238,250
Gross Unrealized Gains	5,430	7,231
Gross Unrealized Losses	(62)	(266)
Estimated Fair Value	240,236	245,215
Corporate Debt Securities [Member]
Schedule of Investments [Line Items]
Amortized Cost	102,297	99,016
Gross Unrealized Gains	2,935	5,126
Gross Unrealized Losses	(5,291)	(6,108)
Estimated Fair Value	99,941	98,034
Collateralized Mortgage Obligations [Member]
Schedule of Investments [Line Items]
Amortized Cost	879,738	917,395
Gross Unrealized Gains	5,638	5,705
Gross Unrealized Losses	(11,077)	(20,787)
Estimated Fair Value	874,299	902,313
Mortgage-Backed Securities [Member]
Schedule of Investments [Line Items]
Amortized Cost	1,036,193	914,797
Gross Unrealized Gains	16,845	16,978
Gross Unrealized Losses	(1,133)	(2,944)
Estimated Fair Value	1,051,905	928,831
Auction Rate Securities [Member]
Schedule of Investments [Line Items]
Amortized Cost	106,661	108,751
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(8,788)	(7,810)
Estimated Fair Value	$ 97,873	$ 100,941

Investment Securities Schedul44

Investment Securities Schedule of Amortized Cost and Fair Values of Debt Securities by Contractual Maturities (Details) $ in Thousands	Sep. 30, 2015USD ($)
Schedule of Investments [Line Items]
Available-for-sale Securities, Debt Maturities, within One Year, Amortized Cost Basis	$ 62,247
Available-for-sale Securities, Debt Maturities, within One Year, Fair Value	63,023
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Amortized Cost Basis	104,989
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Fair Value	107,283
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Amortized Cost Basis	132,930
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Fair Value	136,571
Available-for-sale Securities, Debt Maturities, after Ten Years, Amortized Cost Basis	191,980
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	179,724
Available for Sale Securities, Debt Securities, Amortized Cost, Before Securities Without Debt Maturities	492,146
Available for Sale Securities, Debt Maturities, Before Securities Without Single Maturities	486,601
Available-for-sale Debt Securities, Amortized Cost Basis	2,408,077
Available for Sale, Estimated Fair Value	2,412,805
Collateralized Mortgage Obligations [Member]
Schedule of Investments [Line Items]
Available-for-sale Securities, Debt Maturities, without Single Maturity Date, Amortized Cost Basis	879,738
Available-for-sale Securities, Debt Maturities, without Single Maturity Date, Fair Value	874,299
Mortgage-Backed Securities [Member]
Schedule of Investments [Line Items]
Available-for-sale Securities, Debt Maturities, without Single Maturity Date, Amortized Cost Basis	1,036,193
Available-for-sale Securities, Debt Maturities, without Single Maturity Date, Fair Value	$ 1,051,905

Investment Securities Summary o

Investment Securities Summary of Gains and Losses from Equity and Debt Securities, and Losses from Other-than-Temporary Impairment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Gain (Loss) on Investments [Line Items]
Gross Realized Gains	$ 1,730	$ 99	$ 8,290	$ 1,546
Gross Realized Losses	0	0	0	(323)
Other-than- temporary Impairment Losses	0	(18)	0	(30)
Net Gains (Losses)	1,730	81	8,290	1,193
Equity Securities [Member]
Gain (Loss) on Investments [Line Items]
Gross Realized Gains	1,730	99	5,990	100
Gross Realized Losses	0	0	0	0
Other-than- temporary Impairment Losses	0	0	0	(12)
Net Gains (Losses)	1,730	99	5,990	88
Debt Securities [Member]
Gain (Loss) on Investments [Line Items]
Gross Realized Gains	0	0	2,300	1,446
Gross Realized Losses	0	0	0	(323)
Other-than- temporary Impairment Losses	0	(18)	0	(18)
Net Gains (Losses)	$ 0	$ (18)	$ 2,300	$ 1,105

Investment Securities Summary46

Investment Securities Summary of Cumulative Other-than-Temporary Impairment Charges Recognized as Components of Earnings (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Balance of cumulative credit losses on debt securities, beginning of period	$ (11,510)	$ (17,214)	$ (16,242)	$ (20,691)
Additions for credit losses recorded which were not previously recognized as components of earnings	0	(18)	0	(18)
Reductions for securities sold during the period	0	0	4,730	3,472
Reductions for increases in cash flows expected to be collected that are recognized over the remaining life of the security	0	0	2	5
Balance of cumulative credit losses on debt securities, end of period	$ (11,510)	$ (17,232)	$ (11,510)	$ (17,232)

Investment Securities Gross Unr

Investment Securities Gross Unrealized Losses and Fair Values of Investments by Category and Length of Time in a Continuous Unrealized Loss Position (Details) $ in Thousands	Sep. 30, 2015USD ($)
Schedule of Investments [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 211,680
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(582)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	692,378
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(25,777)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	904,058
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(26,359)
US Government Agencies Debt Securities [Member]
Schedule of Investments [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	0
Municipal Bonds [Member]
Schedule of Investments [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	11,892
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(62)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	11,892
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(62)
Corporate Debt Securities [Member]
Schedule of Investments [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	7,968
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(15)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	33,718
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(5,276)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	41,686
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(5,291)
Collateralized Mortgage Obligations [Member]
Schedule of Investments [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	30,723
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(62)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	493,703
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(11,015)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	524,426
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(11,077)
Mortgage-Backed Securities [Member]
Schedule of Investments [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	161,097
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(443)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	67,071
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(690)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	228,168
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(1,133)
Auction Rate Securities [Member]
Schedule of Investments [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	97,873
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(8,788)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	97,873
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(8,788)
Debt Securities [Member]
Schedule of Investments [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	211,680
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(582)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	692,365
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(25,769)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	904,045
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(26,351)
Equity Securities [Member]
Schedule of Investments [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	13
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(8)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	13
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(8)
U.S. Government-Sponsored Agency Securities [Member]
Schedule of Investments [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	$ 0

Investment Securities Summary48

Investment Securities Summary of Amortized Cost and Fair Values of Corporate Debt Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Debt Securities, Amortized Cost Basis	$ 2,408,077
Corporate debt securities	2,412,805
Corporate Debt Securities Issued by Financial Institutions [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Debt Securities, Amortized Cost Basis	98,249	$ 97,109
Corporate debt securities	95,893	96,127
Single-issuer Trust Preferred Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Debt Securities, Amortized Cost Basis	46,624	47,569
Corporate debt securities	41,787	42,016
Subordinated Debt
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Debt Securities, Amortized Cost Basis	51,625	47,530
Corporate debt securities	53,576	50,023
Pooled Trust Preferred Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Debt Securities, Amortized Cost Basis	0	2,010
Other Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Debt Securities, Amortized Cost Basis	4,048	1,907
Corporate debt securities	4,048	1,907
Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Debt Securities, Amortized Cost Basis	102,297	99,016
Corporate debt securities	$ 99,941	$ 98,034

Investment Securities Narrative

Investment Securities Narrative (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015USD ($)Security	Sep. 30, 2014USD ($)	Sep. 30, 2015USD ($)Security	Sep. 30, 2014USD ($)	Dec. 31, 2014USD ($)
Schedule of Investments [Line Items]
Available-for-sale Securities Pledged as Collateral	$ 1,800,000		$ 1,800,000		$ 1,700,000
Amortized cost	2,424,164		2,424,164		2,312,087
Available-for-sale Securities, Gross Realized Gain (Loss)	1,730	$ 81	8,290	$ 1,193
Available-for-sale Securities, Fair Value Disclosure	2,436,337		2,436,337		2,323,371
Single Bank Stock Investment, cost basis	8,500		8,500
Single Bank Stock Investment, Fair Value	$ 12,800		$ 12,800
Percent Ownership In An Individual Financial Institution	57.10%		57.10%
IndividualBankStockInvestmentPercenttoTotalPortfolio	5.00%		5.00%
Auction Rate Certificates Not Subject To Any Additional Other Than Temporary Impairment Charges Fair Value	$ 97,900		$ 97,900
Domestic Corporate debt securities	99,900		99,900
Equity Securities [Member]
Schedule of Investments [Line Items]
Amortized cost	16,087		16,087		33,469
Available-for-sale Securities, Gross Realized Gain (Loss)	1,730	$ 99	5,990	$ 88
Available-for-sale Securities, Fair Value Disclosure	23,532		23,532		47,623
Equity Securities Financial Institution [Member]
Schedule of Investments [Line Items]
Available-for-sale Securities, Equity Securities	22,400		22,400		41,800
Amortized cost	15,100		15,100
Available-for-sale Securities, Fair Value Disclosure	22,400		22,400
Equity Securities, Other [Member]
Schedule of Investments [Line Items]
Available-for-sale Securities, Equity Securities	1,100		1,100
Auction Rate Securities [Member]
Schedule of Investments [Line Items]
Amortized cost	106,661		106,661		108,751
Available-for-sale Securities, Fair Value Disclosure	97,873		97,873		$ 100,941
Pooled Trust Preferred Securities [Member]
Schedule of Investments [Line Items]
Amortized cost	$ 1,900		1,900
Available-for-sale Securities, Gross Realized Gain (Loss)			$ 2,300
Number of Securities Sold | Security			3
Single-issuer Trust Preferred Securities [Member]
Schedule of Investments [Line Items]
Unrealized Loss on Securities			$ 4,800
Number of Trust Preferred Securities | Security	19		19
Moody's, A2 Rating [Member] | Auction Rate Securities [Member]
Schedule of Investments [Line Items]
Carrying Value Auction Rate Securities Rated Investment Grade	$ 92,000		$ 92,000
Percentage Auction Rate Securities Investment Grade	94.00%		94.00%
Moody's, A3 Rating [Member] | Auction Rate Securities [Member]
Schedule of Investments [Line Items]
Carrying Value Auction Rate Securities Rated Investment Grade	$ 5,000		$ 5,000
Percentage Auction Rate Securities Investment Grade	6.00%		6.00%
External Credit Rating, BBB [Member] | Single-issuer Trust Preferred Securities [Member]
Schedule of Investments [Line Items]
Amortized cost	$ 3,700		$ 3,700
Available-for-sale Securities, Fair Value Disclosure	2,700		2,700
External Credit Rating, Rated Below Investment Grade [Member] | Pooled Trust Preferred Securities [Member]
Schedule of Investments [Line Items]
Amortized cost	0		0
Available-for-sale Securities, Fair Value Disclosure	530		530
External Credit Rating, Rated Below Investment Grade [Member] | Single-issuer Trust Preferred Securities [Member]
Schedule of Investments [Line Items]
Amortized cost	14,500		14,500
Available-for-sale Securities, Fair Value Disclosure	$ 13,200		$ 13,200
Number of Trust Preferred Securities | Security	7		7

Loans and Allowance for Credi50

Loans and Allowance for Credit Losses Summary Of Gross Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	$ 13,551,356	$ 13,124,093
Unearned income	(14,995)	(12,377)
Loans, net of unearned income	13,536,361	13,111,716	$ 13,030,405
Real-estate commercial mortage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	5,339,928	5,197,155
Loans, net of unearned income	5,339,928	5,197,155	5,156,979
Commercial - industrial, financial, and agricultural [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	3,929,908	3,725,567
Loans, net of unearned income	3,929,908	3,725,567	3,691,262
Real-estate - home equity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	1,693,649	1,736,688
Loans, net of unearned income	1,693,649	1,736,688	1,733,036
Real-estate - residential mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	1,382,085	1,377,068
Loans, net of unearned income	1,382,085	1,377,068	1,372,033
Real-estate - construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	769,565	690,601
Loans, net of unearned income	769,565	690,601	687,728
Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	271,696	265,431
Loans, net of unearned income	271,696	265,431	$ 278,219
Leasing and other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	161,911	127,562
Overdrafts [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	$ 2,614	$ 4,021

Loans and Allowance for Credi51

Loans and Allowance for Credit Losses Allowance for Credit Losses (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Jun. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Dec. 31, 2013
Receivables [Abstract]
Allowance for loan losses	$ 167,136	$ 167,485	$ 184,144	$ 189,477	$ 191,685	$ 202,780
Reserve for unfunded lending commitments	2,259		1,787
Allowance for credit losses	$ 169,395	$ 169,453	$ 185,931	$ 191,108	$ 193,442	$ 204,917

Loans and Allowance for Credi52

Loans and Allowance for Credit Losses Activity in the Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	$ 169,453	$ 193,442	$ 185,931	$ 204,917
Loans charged off	(5,561)	(9,604)	(26,697)	(31,348)
Recoveries of loans previously charged off	4,503	3,770	10,661	8,039
Net loans charged off	(1,058)	(5,834)	(16,036)	(23,309)
Provision for credit losses	1,000	3,500	(500)	9,500
Balance at end of period	$ 169,395	$ 191,108	$ 169,395	$ 191,108

Loans and Allowance for Credi53

Loans and Allowance for Credit Losses Allowance for Loan Losses by Portfolio Segment (Details) - USD ($)		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance		$ 167,485,000	$ 191,685,000	$ 184,144,000	$ 202,780,000
Loans charged off		(5,561,000)	(9,604,000)	(26,697,000)	(31,348,000)
Recoveries of loans previously charged off		4,503,000	3,770,000	10,661,000	8,039,000
Net loans charged off		(1,058,000)	(5,834,000)	(16,036,000)	(23,309,000)
Provision for loan losses	[1]	709,000	3,626,000	(972,000)	10,006,000
Ending Balance		167,136,000	189,477,000	167,136,000	189,477,000
Provision for loan losses gross		(291,000)	130,000	(470,000)	506,000
Provision for Loan and Lease Losses		1,000,000	3,500,000	(500,000)	9,500,000
Real-estate commercial mortage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance		50,680,000	49,842,000	53,493,000	55,659,000
Loans charged off		(660,000)	(1,557,000)	(3,011,000)	(5,084,000)
Recoveries of loans previously charged off		842,000	1,167,000	1,729,000	1,641,000
Net loans charged off		182,000	(390,000)	(1,282,000)	(3,443,000)
Provision for loan losses	[1]	825,000	(278,000)	(524,000)	(3,042,000)
Ending Balance		51,687,000	49,174,000	51,687,000	49,174,000
Commercial - industrial, financial, and agricultural [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance		49,170,000	49,084,000	51,378,000	50,330,000
Loans charged off		(1,640,000)	(5,167,000)	(14,669,000)	(15,804,000)
Recoveries of loans previously charged off		1,598,000	1,013,000	3,855,000	2,532,000
Net loans charged off		(42,000)	(4,154,000)	(10,814,000)	(13,272,000)
Provision for loan losses	[1]	(405,000)	6,110,000	8,159,000	13,982,000
Ending Balance		48,723,000	51,040,000	48,723,000	51,040,000
Real-estate - home equity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance		22,506,000	32,041,000	28,271,000	28,222,000
Loans charged off		(940,000)	(1,492,000)	(2,578,000)	(4,377,000)
Recoveries of loans previously charged off		304,000	336,000	744,000	869,000
Net loans charged off		(636,000)	(1,156,000)	(1,834,000)	(3,508,000)
Provision for loan losses	[1]	180,000	406,000	(4,387,000)	6,577,000
Ending Balance		22,050,000	31,291,000	22,050,000	31,291,000
Real-estate - residential mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance		22,787,000	32,744,000	29,072,000	33,082,000
Loans charged off		(1,035,000)	(231,000)	(3,099,000)	(2,166,000)
Recoveries of loans previously charged off		201,000	95,000	547,000	319,000
Net loans charged off		(834,000)	(136,000)	(2,552,000)	(1,847,000)
Provision for loan losses	[1]	(609,000)	397,000	(5,176,000)	1,770,000
Ending Balance		21,344,000	33,005,000	21,344,000	33,005,000
Real-estate - construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance		7,749,000	11,331,000	9,756,000	12,649,000
Loans charged off		(114,000)	(313,000)	(201,000)	(745,000)
Recoveries of loans previously charged off		898,000	470,000	2,276,000	852,000
Net loans charged off		784,000	157,000	2,075,000	107,000
Provision for loan losses	[1]	(964,000)	(312,000)	(4,262,000)	(1,580,000)
Ending Balance		7,569,000	11,176,000	7,569,000	11,176,000
Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance		2,608,000	3,306,000	3,015,000	3,260,000
Loans charged off		(650,000)	(538,000)	(1,787,000)	(1,738,000)
Recoveries of loans previously charged off		314,000	448,000	923,000	1,059,000
Net loans charged off		(336,000)	(90,000)	(864,000)	(679,000)
Provision for loan losses	[1]	282,000	244,000	403,000	879,000
Ending Balance		2,554,000	3,460,000	2,554,000	3,460,000
Leasing and other and overdrafts [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance		1,615,000	1,851,000	1,799,000	3,370,000
Loans charged off		(522,000)	(306,000)	(1,352,000)	(1,434,000)
Recoveries of loans previously charged off		346,000	241,000	587,000	767,000
Net loans charged off		(176,000)	(65,000)	(765,000)	(667,000)
Provision for loan losses	[1]	223,000	180,000	628,000	(737,000)
Ending Balance		1,662,000	1,966,000	1,662,000	1,966,000
Unallocated [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance		10,370,000	11,486,000	7,360,000	16,208,000
Loans charged off		0	0	0	0
Recoveries of loans previously charged off		0	0	0	0
Net loans charged off		0	0	0	0
Provision for loan losses	[1]	1,177,000	(3,121,000)	4,187,000	(7,843,000)
Ending Balance	[2]	$ 11,547,000	$ 8,365,000	$ 11,547,000	$ 8,365,000
[1]	The provision for loan losses excluded a $291,000 and $472,000 increase, respectively, in the reserve for unfunded lending commitments for the three and nine months ended September 30, 2015 and a $126,000 and $506,000 decrease, respectively, in the reserve for unfunded lending commitments for the three and nine months ended September 30, 2014. The total provision for credit losses, comprised of allocations for both funded and unfunded loans, was $1.0 million and negative $500,000, respectively, for the three and nine months ended September 30, 2015 and $3.5 million and $9.5 million, respectively, for the three and nine months ended September 30, 2014.
[2]	The unallocated allowance, which was approximately 7% and 4% of the total allowance for credit losses as of both September 30, 2015 and September 30, 2014, was, in the opinion of management, reasonable and appropriate given that the estimates used in the allocation process are inherently imprecise.

Loans and Allowance for Credi54

Loans and Allowance for Credit Losses Present Loans, Net of Unearned Income and Their Related Allowance for Loan Losses, by Portfolio Segment (Details) - USD ($) $ in Thousands		Sep. 30, 2015		Jun. 30, 2015	Dec. 31, 2014	Sep. 30, 2014		Jun. 30, 2014	Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses measured for impairment under FASB ASC Subtopic 450-20		$ 118,143				$ 124,997
Allowance for loan losses evaluated for impairment under FASB ASC Section 310-10-35		48,993				64,480
Allowance for loan losses		167,136		$ 167,485	$ 184,144	189,477		$ 191,685	$ 202,780
Loans, net of unearned income, measured for impairment under FASB ASC Subtopic 450-20		13,341,850				12,836,973
Loans, net of unearned income, evaluated for impairment under FASB ASC Subtopic 310-10-35		194,511				193,432
Loans, net of unearned income		$ 13,536,361			13,111,716	$ 13,030,405
Percentage of unallocated allowance		7.00%				4.00%
Real-estate commercial mortage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses measured for impairment under FASB ASC Subtopic 450-20		$ 38,490				$ 32,951
Allowance for loan losses evaluated for impairment under FASB ASC Section 310-10-35		13,197				16,223
Allowance for loan losses		51,687		50,680	53,493	49,174		49,842	55,659
Loans, net of unearned income, measured for impairment under FASB ASC Subtopic 450-20		5,273,819				5,095,263
Loans, net of unearned income, evaluated for impairment under FASB ASC Subtopic 310-10-35		66,109				61,716
Loans, net of unearned income		5,339,928			5,197,155	5,156,979
Commercial - industrial, financial, and agricultural [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses measured for impairment under FASB ASC Subtopic 450-20		36,002				39,098
Allowance for loan losses evaluated for impairment under FASB ASC Section 310-10-35		12,721				11,942
Allowance for loan losses		48,723		49,170	51,378	51,040		49,084	50,330
Loans, net of unearned income, measured for impairment under FASB ASC Subtopic 450-20		3,885,956				3,655,162
Loans, net of unearned income, evaluated for impairment under FASB ASC Subtopic 310-10-35		43,952				36,100
Loans, net of unearned income		3,929,908			3,725,567	3,691,262
Home Equity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses measured for impairment under FASB ASC Subtopic 450-20		14,867				21,666
Allowance for loan losses evaluated for impairment under FASB ASC Section 310-10-35		7,183				9,625
Allowance for loan losses		22,050		22,506	28,271	31,291		32,041	28,222
Loans, net of unearned income, measured for impairment under FASB ASC Subtopic 450-20		1,679,471				1,719,049
Loans, net of unearned income, evaluated for impairment under FASB ASC Subtopic 310-10-35		14,178				13,987
Loans, net of unearned income		1,693,649			1,736,688	1,733,036
Real-estate - residential mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses measured for impairment under FASB ASC Subtopic 450-20		7,921				11,503
Allowance for loan losses evaluated for impairment under FASB ASC Section 310-10-35		13,423				21,502
Allowance for loan losses		21,344		22,787	29,072	33,005		32,744	33,082
Loans, net of unearned income, measured for impairment under FASB ASC Subtopic 450-20		1,330,778				1,319,333
Loans, net of unearned income, evaluated for impairment under FASB ASC Subtopic 310-10-35		51,307				52,700
Loans, net of unearned income		1,382,085			1,377,068	1,372,033
Real-estate - construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses measured for impairment under FASB ASC Subtopic 450-20		5,119				6,009
Allowance for loan losses evaluated for impairment under FASB ASC Section 310-10-35		2,450				5,167
Allowance for loan losses		7,569		7,749	9,756	11,176		11,331	12,649
Loans, net of unearned income, measured for impairment under FASB ASC Subtopic 450-20		750,629				658,822
Loans, net of unearned income, evaluated for impairment under FASB ASC Subtopic 310-10-35		18,936				28,906
Loans, net of unearned income		769,565			690,601	687,728
Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses measured for impairment under FASB ASC Subtopic 450-20		2,535				3,439
Allowance for loan losses evaluated for impairment under FASB ASC Section 310-10-35		19				21
Allowance for loan losses		2,554		2,608	3,015	3,460		3,306	3,260
Loans, net of unearned income, measured for impairment under FASB ASC Subtopic 450-20		271,667				278,196
Loans, net of unearned income, evaluated for impairment under FASB ASC Subtopic 310-10-35		29				23
Loans, net of unearned income		271,696			265,431	278,219
Leasing and other and overdrafts [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses measured for impairment under FASB ASC Subtopic 450-20		1,662				1,966
Allowance for loan losses evaluated for impairment under FASB ASC Section 310-10-35		0				0
Allowance for loan losses		1,662		1,615	1,799	1,966		1,851	3,370
Loans, net of unearned income, measured for impairment under FASB ASC Subtopic 450-20		149,530				111,148
Loans, net of unearned income, evaluated for impairment under FASB ASC Subtopic 310-10-35		0				0
Loans, net of unearned income		149,530			119,206	111,148
Unallocated [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses measured for impairment under FASB ASC Subtopic 450-20	[1]	11,547				8,365
Allowance for loan losses		$ 11,547	[1]	$ 10,370	$ 7,360	$ 8,365	[1]	$ 11,486	$ 16,208
[1]	The unallocated allowance, which was approximately 7% and 4% of the total allowance for credit losses as of both September 30, 2015 and September 30, 2014, was, in the opinion of management, reasonable and appropriate given that the estimates used in the allocation process are inherently imprecise.

Loans and Allowance for Credi55

Loans and Allowance for Credit Losses Total Impaired Loans by Class Segments (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Impaired Financing Receivables [Line Items]
Percentage of unallocated allowance	7.00%		4.00%
Unpaid principal balance, with no related allowance	$ 75,399	$ 68,022
Unpaid principal balance, with related allowance	165,756	167,682
Unpaid Principal Balance	241,155	235,704
Recorded investment, with no related allowance	61,583	59,073
Recorded investment, with related allowance	132,928	129,628
Recorded Investment	194,511	188,701
Related Allowance	48,993	60,867
Real-estate commercial mortage [Member]
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with no related allowance	31,961	25,802
Unpaid principal balance, with related allowance	48,734	49,619
Recorded investment, with no related allowance	26,075	23,236
Recorded investment, with related allowance	40,034	40,023
Related Allowance	13,197	16,715
Commercial - Secured [Member]
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with no related allowance	22,097	17,599
Unpaid principal balance, with related allowance	29,415	24,824
Recorded investment, with no related allowance	17,661	14,582
Recorded investment, with related allowance	23,533	19,335
Related Allowance	11,789	12,165
Commercial - unsecured [Member]
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with no related allowance	86	0
Unpaid principal balance, with related allowance	2,832	1,241
Recorded investment, with no related allowance	86	0
Recorded investment, with related allowance	2,672	1,089
Related Allowance	932	865
Real-estate - home equity [Member]
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with no related allowance	0	0
Unpaid principal balance, with related allowance	18,854	19,392
Recorded investment, with no related allowance	0	0
Recorded investment, with related allowance	14,178	13,458
Related Allowance	7,183	9,224
Real-estate - residential mortgage [Member]
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with no related allowance	6,607	4,873
Unpaid principal balance, with related allowance	54,604	56,607
Recorded investment, with no related allowance	6,201	4,873
Recorded investment, with related allowance	45,106	46,478
Related Allowance	13,423	18,592
Construction - commercial residential [Member]
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with no related allowance	13,353	18,041
Unpaid principal balance, with related allowance	9,613	14,007
Recorded investment, with no related allowance	10,417	14,801
Recorded investment, with related allowance	6,019	7,903
Related Allowance	1,985	2,675
Construction - Commercial [Member]
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with no related allowance	1,295	1,707
Unpaid principal balance, with related allowance	1,223	1,501
Recorded investment, with no related allowance	1,143	1,581
Recorded investment, with related allowance	1,077	1,023
Related Allowance	363	459
Construction other [Member]
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	452	452
Recorded investment, with related allowance	280	281
Related Allowance	102	137
Consumer - direct [Member]
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	14	19
Recorded investment, with related allowance	14	19
Related Allowance	10	17
Consumer - Indirect [Member]
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	15	20
Recorded investment, with related allowance	15	19
Related Allowance	$ 9	$ 18

Loans and Allowance for Credi56

Loans and Allowance for Credit Losses Average Impaired Loans by Class Segment (Details) - USD ($) $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 30, 2015		Sep. 30, 2014		Sep. 30, 2015		Sep. 30, 2014
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	$ 60,788		$ 59,286		$ 61,270		$ 62,026
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	158	[1]	165	[1]	538	[1]	529
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	132,780		136,918		133,405		136,888
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	453	[1]	527	[1]	1,445	[1]	1,570
Impaired Financing Receivable, Average Recorded Investment	193,568		196,204		194,675		198,914
Impaired Financing Receivable, Interest Income, Accrual Method	611	[1]	692	[1]	1,983	[1]	2,099
Real-estate commercial mortage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	25,216		23,056		26,033		23,524
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	68	[1]	78	[1]	246	[1]	244
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	40,572		38,469		40,116		37,794
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	110	[1]	130	[1]	368	[1]	394
Commercial - Secured [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	17,609		18,903		16,142		20,014
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	28	[1]	29	[1]	74	[1]	98
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	22,386		19,764		23,668		21,404
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	36	[1]	30	[1]	111	[1]	101
Commercial - unsecured [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	43		0		22		0
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	0	[1]	0	[1]	0	[1]	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	2,788		850		1,981		847
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	1	[1]	1	[1]	4	[1]	3
Real-estate - home equity [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	0		150		0		225
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	0	[1]	0	[1]	0	[1]	1
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	13,728		14,116		13,417		14,106
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	37	[1]	30	[1]	101	[1]	78
Real-estate - residential mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	6,212		1,236		5,539		697
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	34	[1]	7	[1]	94	[1]	13
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	46,039		51,283		46,406		51,257
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	254	[1]	298	[1]	797	[1]	894
Construction - Commercial Residential [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	10,558		14,881		12,390		16,052
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	28	[1]	51	[1]	124	[1]	173
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	5,746		11,189		6,496		10,480
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	15	[1]	38	[1]	64	[1]	100
Construction - Commercial [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	1,150		1,060		1,144		1,514
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	0	[1]	0	[1]	0	[1]	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	1,210		942		1,005		567
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	0	[1]	0	[1]	0	[1]	0
Construction other [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	281		281		281		414
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	0	[1]	0	[1]	0	[1]	0
Consumer - direct [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	15		18		18		15
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	0	[1]	0	[1]	0	[1]	0
Consumer - Indirect [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	15		6		17		4
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	$ 0	[1]	$ 0	[1]	$ 0	[1]	$ 0
[1]	All impaired loans, excluding accruing TDRs, were non-accrual loans. Interest income recognized for the three and nine months ended September 30, 2015 and 2014 represents amounts earned on accruing TDRs.

Loans and Allowance for Credi57

Loans and Allowance for Credit Losses Credit Quality Indicators (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	$ 13,536,361	$ 13,111,716	$ 13,030,405
Commercial Loans, Commerical Mortgages, Constructions Loans [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	$ 9,982,223	$ 9,553,811
Percentage of total loans rated	100.00%	100.00%
Real-estate commercial mortage [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	$ 5,339,928	$ 5,197,155	5,156,979
Commercial - industrial, financial, and agricultural [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	3,929,908	3,725,567	$ 3,691,262
Commercial - Secured [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	3,782,826	3,564,614
Commercial - Unsecured [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	147,082	160,953
Construction, Excluding Contstruction Other [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	712,387	631,089
Construction - Commercial Residential [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	190,521	203,670
Construction - Commercial [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	521,866	427,419
Pass [Member] | Commercial Loans, Commerical Mortgages, Constructions Loans [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	$ 9,406,051	$ 8,924,922
Percentage of total loans rated	94.20%	93.40%
Pass [Member] | Real-estate commercial mortage [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	$ 5,028,655	$ 4,899,016
Pass [Member] | Commercial - industrial, financial, and agricultural [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	3,718,098	3,480,166
Pass [Member] | Commercial - Secured [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	3,579,389	3,333,486
Pass [Member] | Commercial - Unsecured [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	138,709	146,680
Pass [Member] | Construction, Excluding Contstruction Other [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	659,298	545,740
Pass [Member] | Construction - Commercial Residential [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	144,329	136,109
Pass [Member] | Construction - Commercial [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	514,969	409,631
Special Mention [Member] | Commercial Loans, Commerical Mortgages, Constructions Loans [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	$ 252,464	$ 295,046
Percentage of total loans rated	2.50%	3.10%
Special Mention [Member] | Real-estate commercial mortage [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	$ 132,823	$ 127,302
Special Mention [Member] | Commercial - industrial, financial, and agricultural [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	101,185	128,047
Special Mention [Member] | Commercial - Secured [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	97,617	120,584
Special Mention [Member] | Commercial - Unsecured [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	3,568	7,463
Special Mention [Member] | Construction, Excluding Contstruction Other [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	18,456	39,697
Special Mention [Member] | Construction - Commercial Residential [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	16,763	27,495
Special Mention [Member] | Construction - Commercial [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	1,693	12,202
Substandard [Member] | Commercial Loans, Commerical Mortgages, Constructions Loans [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	$ 323,708	$ 333,843
Percentage of total loans rated	3.30%	3.50%
Substandard [Member] | Real-estate commercial mortage [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	$ 178,450	$ 170,837
Substandard [Member] | Commercial - industrial, financial, and agricultural [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	110,625	117,354
Substandard [Member] | Commercial - Secured [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	105,820	110,544
Substandard [Member] | Commercial - Unsecured [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	4,805	6,810
Substandard [Member] | Construction, Excluding Contstruction Other [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	34,633	45,652
Substandard [Member] | Construction - Commercial Residential [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	29,429	40,066
Substandard [Member] | Construction - Commercial [Member]
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Net of Deferred Income	$ 5,204	$ 5,586

Loans and Allowance for Credi58

Loans and Allowance for Credit Losses Summary of Delinquency and Non-Performing Status by Portfolio Segment (Details) $ in Thousands		9 Months Ended
		Sep. 30, 2015USD ($)	Dec. 31, 2014USD ($)	Sep. 30, 2014USD ($)
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income		$ 13,536,361	$ 13,111,716	$ 13,030,405
Real-estate - home equity [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income		1,693,649	1,736,688	1,733,036
Real-estate - residential mortgage [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income		1,382,085	1,377,068	1,372,033
Construction other [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income		57,178	59,512
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income		271,696	265,431	278,219
Consumer - direct [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income		103,234	109,323
Consumer - Indirect [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income		168,462	156,108
Leasing and other and overdrafts [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income		149,530	119,206	$ 111,148
Real Estate, Home Equity, Construction, Other, Consumer and Leasing [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income		3,554,138	3,557,905
Commercial Loans, Commerical Mortgages, Constructions Loans [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income		$ 9,982,223	$ 9,553,811
Loans And Leases Receivable Percentage Of Loans Within Delinquecy Category By Total Non Risk Rated Loans		100.00%	100.00%
Performing Financing Receivable [Member] | Real-estate - home equity [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income		$ 1,671,473	$ 1,711,017
Performing Financing Receivable [Member] | Real-estate - residential mortgage [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income		1,336,877	1,321,139
Performing Financing Receivable [Member] | Construction other [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income		56,482	59,180
Performing Financing Receivable [Member] | Consumer [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income		264,616	257,376
Performing Financing Receivable [Member] | Consumer - direct [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income		98,576	104,018
Performing Financing Receivable [Member] | Consumer - Indirect [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income		166,040	153,358
Performing Financing Receivable [Member] | Leasing and other and overdrafts [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income		148,980	118,550
Performing Financing Receivable [Member] | Real Estate, Home Equity, Construction, Other, Consumer and Leasing [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income		$ 3,478,428	$ 3,467,262
Performing Financing Receivable [Member] | Commercial Loans, Commerical Mortgages, Constructions Loans [Member]
Financing Receivable, Impaired [Line Items]
Loans And Leases Receivable Percentage Of Loans Within Delinquecy Category By Total Non Risk Rated Loans		97.90%	97.50%
Delinquent [Member] | Real-estate - home equity [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	[1]	$ 9,069	$ 10,931
Delinquent [Member] | Real-estate - residential mortgage [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	[1]	17,501	26,934
Delinquent [Member] | Construction other [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	[1]	0	0
Delinquent [Member] | Consumer [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	[1]	5,001	5,465
Delinquent [Member] | Consumer - direct [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	[1]	2,697	2,891
Delinquent [Member] | Consumer - Indirect [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	[1]	2,304	2,574
Delinquent [Member] | Leasing and other and overdrafts [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	[1]	464	523
Delinquent [Member] | Real Estate, Home Equity, Construction, Other, Consumer and Leasing [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	[1]	$ 32,035	$ 43,853
Delinquent [Member] | Commercial Loans, Commerical Mortgages, Constructions Loans [Member]
Financing Receivable, Impaired [Line Items]
Loans And Leases Receivable Percentage Of Loans Within Delinquecy Category By Total Non Risk Rated Loans	[1]	0.90%	1.20%
Nonperforming Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Days past due		90
Nonperforming Financing Receivable [Member] | Real-estate - home equity [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	[2]	$ 13,107	$ 14,740
Nonperforming Financing Receivable [Member] | Real-estate - residential mortgage [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	[2]	27,707	28,995
Nonperforming Financing Receivable [Member] | Construction other [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	[2]	696	332
Nonperforming Financing Receivable [Member] | Consumer [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	[2]	2,079	2,590
Nonperforming Financing Receivable [Member] | Consumer - direct [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	[2]	1,961	2,414
Nonperforming Financing Receivable [Member] | Consumer - Indirect [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	[2]	118	176
Nonperforming Financing Receivable [Member] | Leasing and other and overdrafts [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	[2]	86	133
Nonperforming Financing Receivable [Member] | Real Estate, Home Equity, Construction, Other, Consumer and Leasing [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	[2]	$ 43,675	$ 46,790
Nonperforming Financing Receivable [Member] | Commercial Loans, Commerical Mortgages, Constructions Loans [Member]
Financing Receivable, Impaired [Line Items]
Loans And Leases Receivable Percentage Of Loans Within Delinquecy Category By Total Non Risk Rated Loans	[2]	1.20%	1.30%
Minimum [Member] | Delinquent [Member]
Financing Receivable, Impaired [Line Items]
Days past due		31
Maximum [Member] | Delinquent [Member]
Financing Receivable, Impaired [Line Items]
Days past due		89
[1]	)Includes all accruing loans 31 days to 89 days past due
[2]	Includes all accruing loans 90 days or more past due and all non-accrual loans.

Loans and Allowance for Credi59

Loans and Allowance for Credit Losses Non-Performing Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Receivables [Abstract]
Non-accrual loans	$ 132,154	$ 121,080
Accruing loans 90 days or more past due	12,867	17,402
Total non-performing loans	145,021	138,482
Other real estate owned (OREO)	10,561	12,022
Total non-performing assets	$ 155,582	$ 150,504

Loans and Allowance for Credi60

Loans and Allowance for Credit Losses Loans Modified Under Troubled Debt Restructurings (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Financing Receivable, Modifications [Line Items]
Accruing TDRs	$ 62,357	$ 67,621
Non-accrual TDRs	27,618	24,616	[1]
Total TDRs	89,975	92,237
Real-estate - residential mortgage [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	29,330	31,308
Real-estate commercial mortage [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	17,282	18,822
Construction - Commercial Residential [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	4,363	9,241
Commercial - Secured [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	7,259	5,170
Home Equity [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	3,954	2,975
Commercial - unsecured [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	140	67
Consumer - direct [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	14	19
Consumer Other Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	$ 15	$ 19
[1]	Included within non-accrual loans in the preceding table detailing non-performing assets.

Loans and Allowance for Credi61

Loans and Allowance for Credit Losses Troubled Debt Restructuring Modification (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015USD ($)loans	Sep. 30, 2014USD ($)loans	Sep. 30, 2015USD ($)loans	Sep. 30, 2014USD ($)loans
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	21	13	72	70
Financing Receivable, Modifications, Post-Modification Recorded Investment | $	$ 2,359	$ 2,625	$ 16,050	$ 17,200
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	21	20
Financing Receivable, Modifications, Subsequent Default, Recorded Investment | $	$ 5,047	$ 4,830
Real-estate commercial mortage [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	2	1	6	10
Financing Receivable, Modifications, Post-Modification Recorded Investment | $	$ 188	$ 391	$ 2,815	$ 10,195
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	2	1
Financing Receivable, Modifications, Subsequent Default, Recorded Investment | $	$ 233	$ 35
Real-estate - residential mortgage [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	2	3	10	18
Financing Receivable, Modifications, Post-Modification Recorded Investment | $	$ 229	$ 256	$ 1,295	$ 2,092
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	4	8
Financing Receivable, Modifications, Subsequent Default, Recorded Investment | $	$ 500	$ 1,147
Construction - commercial residential [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	0	0	1	2
Financing Receivable, Modifications, Post-Modification Recorded Investment | $	$ 0	$ 0	$ 889	$ 1,914
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	0	3
Financing Receivable, Modifications, Subsequent Default, Recorded Investment | $	$ 0	$ 2,509
Real-estate - home equity [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	14	6	39	26
Financing Receivable, Modifications, Post-Modification Recorded Investment | $	$ 562	$ 764	$ 1,793	$ 1,627
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	9	5
Financing Receivable, Modifications, Subsequent Default, Recorded Investment | $	$ 459	$ 724
Commercial - Secured [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	3	3	14	4
Financing Receivable, Modifications, Post-Modification Recorded Investment | $	$ 1,380	$ 1,214	$ 9,203	$ 1,357
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	6	3
Financing Receivable, Modifications, Subsequent Default, Recorded Investment | $	$ 3,855	$ 415
Commercial - unsecured [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	0	0	1	0
Financing Receivable, Modifications, Post-Modification Recorded Investment | $	$ 0	$ 0	$ 42	$ 0
Consumer - direct [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	0	0	0	6
Financing Receivable, Modifications, Post-Modification Recorded Investment | $	$ 0	$ 0	$ 0	$ 8
Consumer - Indirect [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	0	0	1	4
Financing Receivable, Modifications, Post-Modification Recorded Investment | $	$ 0	$ 0	$ 13	$ 7

Loans and Allowance for Credi62

Loans and Allowance for Credit Losses Past Due Loan Status and Non-Accrual Loans by Portfolio Segment (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Financial Receivable, Recorded investment, Past Due [Line Items]
>90 Days Past Due and Accruing	$ 12,867	$ 17,402
Non-accrual	132,154	121,080
Total Past Due	201,715	206,828
Current	13,334,646	12,904,888
Loans, net of unearned income	13,536,361	13,111,716	$ 13,030,405
Real-estate commercial mortage [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
>90 Days Past Due and Accruing	194	800
Non-accrual	48,827	44,437
Total Past Due	57,512	63,313
Current	5,282,416	5,133,842
Loans, net of unearned income	5,339,928	5,197,155	5,156,979
Commercial - industrial, financial, and agricultural [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
>90 Days Past Due and Accruing	1,479	619
Non-accrual	36,553	29,769
Total Past Due	51,872	36,645
Current	3,878,036	3,688,922
Loans, net of unearned income	3,929,908	3,725,567	3,691,262
Commercial - Secured [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
>90 Days Past Due and Accruing	1,414	610
Non-accrual	33,935	28,747
Total Past Due	46,794	35,154
Current	3,736,032	3,529,460
Loans, net of unearned income	3,782,826	3,564,614
Commercial - unsecured [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
>90 Days Past Due and Accruing	65	9
Non-accrual	2,618	1,022
Total Past Due	5,078	1,491
Current	142,004	159,462
Loans, net of unearned income	147,082	160,953
Real-estate - home equity [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
>90 Days Past Due and Accruing	2,883	4,257
Non-accrual	10,224	10,483
Total Past Due	22,176	25,671
Current	1,671,473	1,711,017
Loans, net of unearned income	1,693,649	1,736,688	1,733,036
Real-estate - residential mortgage [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
>90 Days Past Due and Accruing	5,730	8,952
Non-accrual	21,977	20,043
Total Past Due	45,208	55,929
Current	1,336,877	1,321,139
Loans, net of unearned income	1,382,085	1,377,068	1,372,033
Construction - Commercial Residential [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
>90 Days Past Due and Accruing	0	0
Non-accrual	12,073	13,463
Total Past Due	14,136	13,623
Current	176,385	190,047
Loans, net of unearned income	190,521	203,670
Construction - Commercial [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
>90 Days Past Due and Accruing	0	0
Non-accrual	2,220	2,604
Total Past Due	2,485	2,604
Current	519,381	424,815
Loans, net of unearned income	521,866	427,419
Construction other [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
>90 Days Past Due and Accruing	416	51
Non-accrual	280	281
Total Past Due	696	332
Current	56,482	59,180
Loans, net of unearned income	57,178	59,512
Real-estate - construction [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
>90 Days Past Due and Accruing	416	51
Non-accrual	14,573	16,348
Total Past Due	17,317	16,559
Current	752,248	674,042
Loans, net of unearned income	769,565	690,601	687,728
Consumer [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
>90 Days Past Due and Accruing	2,079	2,590
Non-accrual	0	0
Total Past Due	7,080	8,055
Current	264,616	257,376
Loans, net of unearned income	271,696	265,431	278,219
Consumer - direct [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
>90 Days Past Due and Accruing	1,961	2,414
Non-accrual	0	0
Total Past Due	4,658	5,305
Current	98,576	104,018
Loans, net of unearned income	103,234	109,323
Consumer - Indirect [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
>90 Days Past Due and Accruing	118	176
Non-accrual	0	0
Total Past Due	2,422	2,750
Current	166,040	153,358
Loans, net of unearned income	168,462	156,108
Leasing and other and overdrafts [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
>90 Days Past Due and Accruing	86	133
Non-accrual	0	0
Total Past Due	550	656
Current	148,980	118,550
Loans, net of unearned income	149,530	119,206	$ 111,148
Financing Receivables, 30 to 59 Days Past Due [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	40,328	51,177
Financing Receivables, 30 to 59 Days Past Due [Member] | Real-estate commercial mortage [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	7,322	14,399
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial - industrial, financial, and agricultural [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	9,289	5,234
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial - Secured [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	6,909	4,839
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial - unsecured [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	2,380	395
Financing Receivables, 30 to 59 Days Past Due [Member] | Real-estate - home equity [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	6,312	8,048
Financing Receivables, 30 to 59 Days Past Due [Member] | Real-estate - residential mortgage [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	11,499	18,789
Financing Receivables, 30 to 59 Days Past Due [Member] | Construction - Commercial Residential [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	1,832	160
Financing Receivables, 30 to 59 Days Past Due [Member] | Construction - Commercial [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	265	0
Financing Receivables, 30 to 59 Days Past Due [Member] | Construction other [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	0	0
Financing Receivables, 30 to 59 Days Past Due [Member] | Real-estate - construction [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	2,097	160
Financing Receivables, 30 to 59 Days Past Due [Member] | Consumer [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	3,360	4,190
Financing Receivables, 30 to 59 Days Past Due [Member] | Consumer - direct [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	1,398	2,034
Financing Receivables, 30 to 59 Days Past Due [Member] | Consumer - Indirect [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	1,962	2,156
Financing Receivables, 30 to 59 Days Past Due [Member] | Leasing and other and overdrafts [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	449	357
Financing Receivables, 60 to 89 Days Past Due [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	16,366	17,169
Financing Receivables, 60 to 89 Days Past Due [Member] | Real-estate commercial mortage [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	1,169	3,677
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial - industrial, financial, and agricultural [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	4,551	1,023
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial - Secured [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	4,536	958
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial - unsecured [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	15	65
Financing Receivables, 60 to 89 Days Past Due [Member] | Real-estate - home equity [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	2,757	2,883
Financing Receivables, 60 to 89 Days Past Due [Member] | Real-estate - residential mortgage [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	6,002	8,145
Financing Receivables, 60 to 89 Days Past Due [Member] | Construction - Commercial Residential [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	231	0
Financing Receivables, 60 to 89 Days Past Due [Member] | Construction - Commercial [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	0	0
Financing Receivables, 60 to 89 Days Past Due [Member] | Construction other [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	0	0
Financing Receivables, 60 to 89 Days Past Due [Member] | Real-estate - construction [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	231	0
Financing Receivables, 60 to 89 Days Past Due [Member] | Consumer [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	1,641	1,275
Financing Receivables, 60 to 89 Days Past Due [Member] | Consumer - direct [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	1,299	857
Financing Receivables, 60 to 89 Days Past Due [Member] | Consumer - Indirect [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	342	418
Financing Receivables, 60 to 89 Days Past Due [Member] | Leasing and other and overdrafts [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	15	166
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	145,021	138,482
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Real-estate commercial mortage [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	49,021	45,237
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial - industrial, financial, and agricultural [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	38,032	30,388
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial - Secured [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	35,349	29,357
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial - unsecured [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	2,683	1,031
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Real-estate - home equity [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	13,107	14,740
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Real-estate - residential mortgage [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	27,707	28,995
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Construction - Commercial Residential [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	12,073	13,463
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Construction - Commercial [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	2,220	2,604
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Construction other [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	696	332
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Real-estate - construction [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	14,989	16,399
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Consumer [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	2,079	2,590
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Consumer - direct [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	1,961	2,414
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Consumer - Indirect [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	118	176
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Leasing and other and overdrafts [Member]
Financial Receivable, Recorded investment, Past Due [Line Items]
Total Past Due	$ 86	$ 133

Loans and Allowance for Credi63

Loans and Allowance for Credit Losses Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Provision for Loan and Lease Losses	$ 1,000	$ 3,500	$ (500)	$ 9,500
Allowance for Loan and Lease Losses, Period Increase (Decrease)			$ 10,000
Impaired loans with principal balances approximately in percentage			77.00%
Loan to value ratio in the Corporation's policy	70.00%		70.00%
Recorded investment, with no related allowance	$ 61,583		$ 61,583		$ 59,073
TDR additional commitments to lend	5,300		5,300		$ 3,900
Maximum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Minimum balance of loans evaluated individually for impairment			1,000
Minimum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Minimum balance of loans evaluated individually for impairment			1,000
Impaired loans balances, real estate as collateral	$ 1,000		$ 1,000

Mortgage Servicing Rights Summa

Mortgage Servicing Rights Summary of Changes in Mortgage Servicing Rights (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Amortized Cost:
Servicing Asset at Fair Value, Amount	$ 43,800		$ 43,800
Mortgages [Member]
Amortized Cost:
Valuation Allowance for Impairment of Recognized Servicing Assets, Period Increase (Decrease)			0	$ 0
Residential Mortgage [Member]
Amortized Cost:
Balance at beginning of period	41,598	$ 42,586	42,148	42,452
Originations of mortgage servicing rights	1,463	1,456	4,976	3,807
Amortization	(1,829)	(1,664)	(5,892)	(3,881)
Balance at end of period	$ 41,232	$ 42,378	$ 41,232	$ 42,378

Stock-Based Compensation Compen

Stock-Based Compensation Compensation Expense and Related Tax Benefits (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-based compensation expense	$ 1,533	$ 1,288	$ 4,371	$ 4,310
Tax benefit	(489)	(358)	(1,403)	(1,067)
Stock-based compensation expense, net of tax	$ 1,044	$ 930	$ 2,968	$ 3,243

Stock-Based Compensation Narrat

Stock-Based Compensation Narrative (Details) shares in Thousands	9 Months Ended
	Sep. 30, 2015shares
Statement [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award Options Expiration Term	10 years
Directors' Plan [Member]
Statement [Line Items]
Shares reserved for future grants under the stock option and compensation plan	396
Employee Stock Option [Member]
Statement [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period 1	3 years
Shares reserved for future grants under the stock option and compensation plan	11,600

Employee Benefit Plans Summary

Employee Benefit Plans Summary of Pension Plan and Postretirement Plan Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands		Feb. 01, 2014	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Pension Plan [Member]
Define Benefit Plan Disclosure [Line Items]
Service cost	[1]		$ 145	$ 92	$ 435	$ 276
Interest cost			851	853	2,553	2,559
Expected return on plan assets			(752)	(811)	(2,256)	(2,432)
Net amortization and deferral			782	244	2,346	732
Net periodic benefit cost			1,026	378	3,078	1,135
Postretirement Plan [Member]
Define Benefit Plan Disclosure [Line Items]
Service cost	[2]		0	0	0	15
Interest cost			52	48	156	157
Net accretion and deferral			(65)	(84)	(195)	(263)
Net periodic benefit cost			(13)	$ (36)	$ (39)	$ (91)
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Curtailments		$ 1,500
Defined Benefit Plan, Curtailments			$ 3,400
[1]	The Pension Plan service cost recorded for the nine months ended September 30, 2015 and 2014 was related to administrative costs associated with the plan and was not due to the accrual of additional participant benefits.
[2]	As a result of the plan amendment, additional participant benefits are not accrued under the Postretirement Plan after February 1, 2014.

Derivative Financial Instrume68

Derivative Financial Instruments Notional Amounts and Fair Values of Derivative Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Derivative [Line Items]
Foreign Currency Open Position	$ 500,000
Derivative asset, fair value	38,137	$ 20,360
Derivative liability, fair value	37,857	20,790
Derivative asset (liability), net	1,030	160
Interest Rate Lock Commitments [Member]
Derivative [Line Items]
Derivative asset, notional amount	121,546	89,655
Derivative liability, notional amount	172	301
Derivative asset, fair value	2,263	1,391
Derivative liability, fair value	2	6
Derivative asset (liability), net	2,261	1,385
Forward Commitments [Member]
Derivative [Line Items]
Derivative asset, notional amount	110	0
Derivative liability, notional amount	117,389	93,802
Derivative asset, fair value	0	0
Derivative liability, fair value	1,502	1,164
Derivative asset (liability), net	(1,502)	(1,164)
Interest Rate Swap with Customer [Member]
Derivative [Line Items]
Derivative asset, notional amount	681,647	468,080
Derivative liability, notional amount	8,000	25,418
Derivative asset, fair value	37,436	19,716
Derivative liability, fair value	87	198
Derivative asset (liability), net	37,349	19,518
Interest Rate Swap with Counterparty [Member]
Derivative [Line Items]
Derivative asset, notional amount	8,000	25,418
Derivative liability, notional amount	681,647	468,080
Derivative asset, fair value	87	198
Derivative liability, fair value	37,436	19,716
Derivative asset (liability), net	(37,349)	(19,518)
Foreign Exchange Contracts With Customer [Member]
Derivative [Line Items]
Derivative asset, notional amount	7,183	11,616
Derivative liability, notional amount	7,091	5,250
Derivative asset, fair value	260	810
Derivative liability, fair value	269	441
Derivative asset (liability), net	(9)	369
Foreign Exchange Contracts With Correspondent Banks [Member]
Derivative [Line Items]
Derivative asset, notional amount	10,308	5,287
Derivative liability, notional amount	8,630	13,572
Derivative asset, fair value	614	446
Derivative liability, fair value	334	876
Derivative asset (liability), net	$ 280	$ (430)

Derivative Financial Instrume69

Derivative Financial Instruments Fair Value Gains and Losses on Derivative Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Mortgage Banking Income [Member] | Interest rate lock with customers [Member]
Derivative [Line Items]
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	$ 1,041	$ (1,092)	$ 876	$ 500
Mortgage Banking Income [Member] | Forward Commitments [Member]
Derivative [Line Items]
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	(3,183)	1,374	(338)	(1,627)
Other Income [Member]
Derivative [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Income, Net	(2,016)	312	870	(1,166)
Other Income [Member] | Interest Rate Swap with Customer [Member]
Derivative [Line Items]
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	18,266	(40)	17,831	10,300
Other Income [Member] | Interest Rate Swap with Counterparty [Member]
Derivative [Line Items]
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	(18,266)	40	(17,831)	(10,300)
Other Income [Member] | Foreign Exchange Contracts With Customer [Member]
Derivative [Line Items]
Gain (Loss) on Foreign Currency Derivatives Recorded in Earnings, Net	(197)	557	(378)	854
Other Income [Member] | Foreign Exchange Contracts With Correspondent Banks [Member]
Derivative [Line Items]
Gain (Loss) on Foreign Currency Derivatives Recorded in Earnings, Net	$ 323	$ (527)	$ 710	$ (893)

Fair Value Option Summary of Co

Fair Value Option Summary of Corporation's Mortgage Loans Held for Sale (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Fair Value, Option, Quantitative Disclosures [Line Items]
Loans Held-for-sale, Mortgages	$ 26,937		$ 26,937		$ 17,522
Mortgage Loans Held For Sale [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Gain (loss) in fair values of mortgage loans held for sale	531	$ (472)	309	$ 343
Mortgage Loans Held For Sale [Member] | Cost [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Loans Held-for-sale, Mortgages	26,186		26,186		17,080
Mortgage Loans Held For Sale [Member] | Fair Value [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Loans Held-for-sale, Mortgages	$ 26,937		$ 26,937		$ 17,522

Balance Sheet Offsetting (Detai

Balance Sheet Offsetting (Details) - USD ($) $ in Thousands		Sep. 30, 2015	Dec. 31, 2014
Offsetting Assets [Line Items]
Gross Amounts Recognized on the Consolidated Balance Sheets		$ 38,137	$ 20,360
Gross Amounts Not Offset on the Consolidated Balance Sheets, Financial Instruments	[1]	(421)	(652)
Gross Amounts Not Offset on the Consolidated Balance Sheets, Cash Collateral	[2]	0	0
Net Amount		37,716	19,708
Offsetting Liabilities [Line Items]
Gross Amounts Recognized on the Consolidated Balance Sheets		37,857	20,790
Gross Amounts Not Offset on the Consolidated Balance Sheets, Financial Instruments	[1]	(421)	(652)
Gross Amounts Not Offset on the Consolidated Balance Sheets, Cash Collateral	[2]	(37,126)	(19,520)
Net Amount		310	618
Foreign Exchange Contract [Member]
Offsetting Assets [Line Items]
Gross Amounts Recognized on the Consolidated Balance Sheets		614	446
Gross Amounts Not Offset on the Consolidated Balance Sheets, Financial Instruments	[1]	(334)	(446)
Gross Amounts Not Offset on the Consolidated Balance Sheets, Cash Collateral	[2]	0
Net Amount		280
Offsetting Liabilities [Line Items]
Gross Amounts Recognized on the Consolidated Balance Sheets		334	876
Gross Amounts Not Offset on the Consolidated Balance Sheets, Financial Instruments	[1]	(334)	(446)
Gross Amounts Not Offset on the Consolidated Balance Sheets, Cash Collateral	[2]	310	(310)
Net Amount		310	120
Interest Rate Swap [Member]
Offsetting Assets [Line Items]
Gross Amounts Recognized on the Consolidated Balance Sheets		37,523	19,914
Gross Amounts Not Offset on the Consolidated Balance Sheets, Financial Instruments	[1]	(87)	(206)
Gross Amounts Not Offset on the Consolidated Balance Sheets, Cash Collateral	[2]	0	0
Net Amount		37,436	19,708
Offsetting Liabilities [Line Items]
Gross Amounts Recognized on the Consolidated Balance Sheets		37,523	19,914
Gross Amounts Not Offset on the Consolidated Balance Sheets, Financial Instruments	[1]	(87)	(206)
Gross Amounts Not Offset on the Consolidated Balance Sheets, Cash Collateral	[2]	(37,436)	(19,210)
Net Amount		$ 0	$ 498
[1]	For interest rate swap and foreign exchange derivative assets, amounts represent any derivative liability fair values that could be offset in the event of counterparty or customer default. For interest rate swap and foreign exchange derivative liabilities, amounts represent any derivative asset fair values that could be offset in the event of counterparty or customer default.
[2]	Amounts represent cash collateral posted on interest rate swap transactions with financial institution counterparties. Interest rate swaps with customers are collateralized by the underlying loans to those borrowers.

Commitments and Contingencies O

Commitments and Contingencies Outstanding Commitments to Extend Credit and Letters of Credit (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Residential Mortgage Principal Balance Repurchase Request Received	$ 851	$ 543
Residential Mortgage Principal Balance FHLB Credit Enhancement	132,000
Residential Mortgage Repurchase Reserves FHLB Credit Enhancement	1,800	2,300
Commitments to Extend Credit [Member] | Reserve for Off-balance Sheet Activities [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Valuation allowances and Reserves, Balance	5,635,629	4,389,064
Standby Letters of Credit [Member] | Reserve for Off-balance Sheet Activities [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Valuation allowances and Reserves, Balance	390,501	382,465
Commercial Letters of Credit [Member] | Reserve for Off-balance Sheet Activities [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Valuation allowances and Reserves, Balance	36,365	32,304
Residential Mortgage [Member] | Reserve for Off-balance Sheet Activities [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Valuation allowances and Reserves, Balance	$ 2,500	$ 3,200

Fair Value Measurements Assets

Fair Value Measurements Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	$ 2,436,337	$ 2,323,371
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgages Held-for-sale, Fair Value Disclosure	26,937	17,522
Available-for-sale Securities, Fair Value Disclosure	2,436,337	2,323,371
Other Assets, Fair Value Disclosure	56,040	38,987
Assets, Fair Value Disclosure	2,519,314	2,379,880
Liabilities, Fair Value Disclosure	55,009	38,821
Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	23,532	47,623
Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	23,532	47,623
U.S. Government Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure		200
U.S. Government Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure		200
U.S. Government-Sponsored Agency Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	48,551	214
U.S. Government-Sponsored Agency Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	48,551	214
State and Municipal Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	240,236	245,215
State and Municipal Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	240,236	245,215
Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	99,941	98,034
Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	99,941	98,034
Collateralized Mortgage Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	874,299	902,313
Collateralized Mortgage Obligations [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	874,299	902,313
Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	1,051,905	928,831
Mortgage-Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	1,051,905	928,831
Auction Rate Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	97,873	100,941
Auction Rate Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	97,873	100,941
Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgages Held-for-sale, Fair Value Disclosure	0	0
Available-for-sale Securities, Fair Value Disclosure	23,532	47,623
Other Assets, Fair Value Disclosure	16,253	17,682
Assets, Fair Value Disclosure	39,785	65,305
Liabilities, Fair Value Disclosure	15,982	17,737
Fair Value, Inputs, Level 1 [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	23,532	47,623
Fair Value, Inputs, Level 1 [Member] | U.S. Government Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure		0
Fair Value, Inputs, Level 1 [Member] | U.S. Government-Sponsored Agency Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 1 [Member] | State and Municipal Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 1 [Member] | Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 1 [Member] | Collateralized Mortgage Obligations [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 1 [Member] | Mortgage-Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 1 [Member] | Auction Rate Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgages Held-for-sale, Fair Value Disclosure	26,937	17,522
Available-for-sale Securities, Fair Value Disclosure	2,311,752	2,166,899
Other Assets, Fair Value Disclosure	39,787	21,305
Assets, Fair Value Disclosure	2,378,476	2,205,726
Liabilities, Fair Value Disclosure	39,027	21,084
Fair Value, Inputs, Level 2 [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 2 [Member] | U.S. Government Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure		200
Fair Value, Inputs, Level 2 [Member] | U.S. Government-Sponsored Agency Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	48,551	214
Fair Value, Inputs, Level 2 [Member] | State and Municipal Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	240,236	245,215
Fair Value, Inputs, Level 2 [Member] | Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	96,761	90,126
Fair Value, Inputs, Level 2 [Member] | Collateralized Mortgage Obligations [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	874,299	902,313
Fair Value, Inputs, Level 2 [Member] | Mortgage-Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	1,051,905	928,831
Fair Value, Inputs, Level 2 [Member] | Auction Rate Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgages Held-for-sale, Fair Value Disclosure	0	0
Available-for-sale Securities, Fair Value Disclosure	101,053	108,849
Other Assets, Fair Value Disclosure	0	0
Assets, Fair Value Disclosure	101,053	108,849
Liabilities, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 3 [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 3 [Member] | U.S. Government Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure		0
Fair Value, Inputs, Level 3 [Member] | U.S. Government-Sponsored Agency Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 3 [Member] | State and Municipal Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 3 [Member] | Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	3,180	7,908
Fair Value, Inputs, Level 3 [Member] | Collateralized Mortgage Obligations [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 3 [Member] | Mortgage-Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 3 [Member] | Auction Rate Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	$ 97,873	$ 100,941

Fair Value Measurements Changes

Fair Value Measurements Changes in Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Level 3 Inputs (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Equity Securities, Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Equity Securities		$ 1,100		$ 1,100
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Equity Securities, Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Equity Securities		1,100		1,100		$ 5,800
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Pooled Trust Preferred Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period		530	$ 4,275	4,088	$ 5,306
Unrealized adjustment to fair value	[1]	0	230	190	789
(Premium amortization) discount accretion	[2]	0	0	2	4
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	[3]		(18)		(18)
Sales				(3,633)	(1,394)
Settlements - calls		0		(117)	(200)
Balance, end of period		530	4,487	530	4,487
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Single-issuer Trust Preferred Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period		3,820	3,820	3,820	3,781
Unrealized adjustment to fair value	[1]	(203)	47	(207)	83
(Premium amortization) discount accretion	[2]	3	2	7	5
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	[3]		0		0
Sales				0	0
Settlements - calls		(970)		(970)	0
Balance, end of period		2,650	3,869	2,650	3,869
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Auction Rate Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period		98,606	146,931	100,941	159,274
Unrealized adjustment to fair value	[1]	(890)	1,280	(978)	1,528
(Premium amortization) discount accretion	[2]	157	262	356	664
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	[3]		0		0
Sales				0	(11,912)
Settlements - calls		0		(2,446)	(1,081)
Balance, end of period		$ 97,873	$ 148,473	$ 97,873	$ 148,473
[1]	Pooled trust preferred securities, single-issuer trust preferred securities and ARCs are classified as available for sale investment securities; as such, the unrealized adjustment to fair value was recorded as an unrealized holding gain (loss) and included as a component of available for sale investment securities on the consolidated balance sheets.
[2]	Included as a component of net interest income on the consolidated statements of income.
[3]	Realized adjustments to fair value represent credit related other-than-temporary impairment charges and gains on sales of investment securities, both included as components of investment securities gains on the consolidated statements of income.

Fair Value Measurements Asset75

Fair Value Measurements Assets Measured at Fair Value on a Nonrecurring Basis (Details) - Fair Value, Measurements, Nonrecurring [Member] - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net loans	$ 145,518	$ 127,834
Other financial assets	51,794	54,170
Assets, Fair Value Disclosure	197,312	182,004
Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net loans	0	0
Other financial assets	0	0
Assets, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net loans	0	0
Other financial assets	0	0
Assets, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net loans	145,518	127,834
Other financial assets	51,794	54,170
Assets, Fair Value Disclosure	$ 197,312	$ 182,004

Fair Value Measurements Details

Fair Value Measurements Details of Book Value and Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands		Sep. 30, 2015	Dec. 31, 2014
Fair Value, Balance Sheet Grouping, FinancialStatement Captions[Line Items]
Available for sale investment securities		$ 2,436,337	$ 2,323,371
Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, FinancialStatement Captions[Line Items]
Cash and Cash Equivalents		93,803	105,702
Interest-Rate Deposits with Other Banks		510,943	358,130
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure		68,977	64,953
Loans Held-for-sale	[1]	26,937	17,522
Available for sale investment securities	[1]	2,436,337	2,323,371
Loans, net of unearned income	[1]	13,536,361	13,111,716
Accrued Interest Receivable		42,846	41,818
Other Financial Assets	[1]	174,835	169,764
Demand and Savings Deposit Liabilities, Fair Value Disclosure		11,148,667	10,296,055
Time Deposit Liabilities, Fair Value Disclosure		2,935,727	3,071,451
Short-term borrowings		431,631	329,719
Accrued interest payable		14,727	18,045
Other Financial Liabilities	[1]	192,281	172,786
Federal Home Loan Bank Advances And Debt Long Term, Fair Value Disclosre		979,433	1,139,413
Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, FinancialStatement Captions[Line Items]
Cash and Cash Equivalents		93,803	105,702
Interest-Rate Deposits with Other Banks		510,943	358,130
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure		68,977	64,953
Loans Held-for-sale	[1]	26,937	17,522
Available for sale investment securities	[1]	2,436,337	2,323,371
Loans, net of unearned income	[1]	13,428,016	13,030,543
Accrued Interest Receivable		42,846	41,818
Other Financial Assets	[1]	174,835	169,764
Demand and Savings Deposit Liabilities, Fair Value Disclosure		11,148,667	10,296,055
Time Deposit Liabilities, Fair Value Disclosure		2,944,618	3,069,883
Short-term borrowings		431,631	329,719
Accrued interest payable		14,727	18,045
Other Financial Liabilities	[1]	192,281	172,786
Federal Home Loan Bank Advances And Debt Long Term, Fair Value Disclosre		$ 1,002,761	$ 1,142,980
[1]	These financial instruments, or certain financial instruments within these categories, are measured at fair value on the Corporation’s consolidated balance sheets. Descriptions of the fair value determinations for these financial instruments are disclosed above.

Fair Value Measurements Narrati

Fair Value Measurements Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Equity Securities, Value Test Coverage, Percent	80.00%
Fair Value, Equity Securities, Fair Value Price Difference Threshold, Percent	5.00%
Corporate debt securities	$ 2,412,805
Significant Input, Assumed Market Return to Liquidity, Years	5 years
Other real estate owned (OREO)	$ 10,561	$ 12,022
Short Term Borrowings, Reprice Period, In Days	90
Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Prepayment Speed	11.60%
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Discount Rate	9.60%
Equity Securities Financial Institution [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Equity Securities	$ 22,400	41,800
Equity Securities, Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Equity Securities	1,100
Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Corporate debt securities	99,941	98,034
Single-issuer Trust Preferred Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Corporate debt securities	41,787	42,016
Fair Value, Measurements, Recurring [Member] | Single-issuer Trust Preferred Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Corporate debt securities	41,800	42,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Equity Securities Financial Institution [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Equity Securities	22,400	41,800
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Equity Securities, Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Equity Securities	1,100	5,800
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Financial Institutions Subordinated Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Corporate debt securities	53,600	50,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Single-issuer Trust Preferred Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Corporate debt securities	39,200	38,200
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Other Corporate Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Corporate debt securities	4,000	1,900
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Single-issuer Trust Preferred Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Corporate debt securities	2,700	3,800
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Pooled Trust Preferred Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Corporate debt securities	500	4,100
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other real estate owned (OREO)	10,600	12,000
Servicing Asset at Amortized Value, Fair Value	41,200	42,100
Trust for Benefit of Employees [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other financial assets	15,400	16,400
Foreign Exchange Contract [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other financial assets	900	1,300
Forward Contracts [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other financial assets	2,300	1,400
Other financial liabilities	1,500	1,200
Interest Rate Swap [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other financial assets	37,500	19,900
Other financial liabilities	37,500	19,900
Foreign Exchange Contract [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other financial liabilities	600	1,300
Trust for Benefit of Employees [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other financial liabilities	$ 15,400	$ 16,400

Common Stock Repurchase Plans (

Common Stock Repurchase Plans (Details) - USD ($) $ / shares in Units, shares in Millions	1 Months Ended		6 Months Ended	9 Months Ended
	Apr. 30, 2015	Nov. 30, 2014	Apr. 30, 2015	Sep. 30, 2015	Sep. 30, 2014
Stockholders' Equity Note [Abstract]
Stock repurchase program, authorized amount	$ 50,000,000	$ 100,000,000	$ 50,000,000
Payments for repurchase of common stock		$ 100,000,000		$ 50,000,000	$ 95,255,000
Acquisition of treasury stock (in shares)	1.8	6.5	8.3	4
Share repurchase plan, percent of common shares outstanding, expected to be delivered		80.00%
Treasury stock aquired, average cost per share	$ 12.05			$ 12.57
Stock repurchase plan, authorized amount	2.30%

Long-Term Debt (Details)

Long-Term Debt (Details) - USD ($)	1 Months Ended		3 Months Ended		9 Months Ended
	Jul. 31, 2015	Jun. 30, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Debt Instrument [Line Items]
Loss on redemption of trust preferred securities			$ 5,626,000	$ 0	$ 5,626,000	$ 0
Reclassification adjustment for loss on derivative financial instruments included in net income			2,456,000	$ 0	2,456,000	$ 0
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax			(1,322,000)		(1,322,000)
Subordinated Debt
Debt Instrument [Line Items]
Debt instrument, face amount			$ 150,000,000		$ 150,000,000
Debt instrument, term		10 years
Subordinated borrowing, interest rate		4.50%
Debt instrument, effective interest rate			4.69%		4.69%
Fulton Capital Trust I | Junior Subordinated Debt
Debt Instrument [Line Items]
Subordinated borrowing, interest rate	6.29%
Debt instrument, effective interest rate			6.52%		6.52%
Repayments of subordinated debt	$ 150,000,000
Loss on redemption of trust preferred securities	$ 5,600,000

Subsequent Event (Details)

Subsequent Event (Details) - USD ($)	1 Months Ended
	Oct. 31, 2015	Apr. 30, 2015	Nov. 30, 2014
Subsequent Event [Line Items]
Stock repurchase plan, authorized amount		2.30%
Stock repurchase program, authorized amount		$ 50,000,000	$ 100,000,000
Subsequent Event
Subsequent Event [Line Items]
Stock repurchase plan, authorized amount	2.30%
Stock repurchase program, authorized amount	$ 50,000,000