PrivateBancorp (PVTB) 10-Q 8 May 15 2015 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Mar. 31, 2015	7-May-15
Entity Information [Line Items]
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	31-Mar-15
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Entity Registrant Name	PRIVATEBANCORP, INC
Entity Central Index Key	889936
Current Fiscal Year End Date	-19
Entity Filer Category	Large Accelerated Filer
Common Stock [Member]
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		78,612,280
Nonvoting Common Stock [Member]
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		0

Consolidated_Statements_Of_Fin

Consolidated Statements Of Financial Condition (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Assets
Cash and due from banks	$158,431	$132,211
Federal funds sold and interest-bearing deposits in banks	799,953	292,341
Loans held-for-sale	89,461	115,161
Securities available-for-sale, at fair value (pledged as collateral to creditors: $86.1 million - 2015; $86.5 million - 2014)	1,631,237	1,645,344
Securities held-to-maturity, at amortized cost (fair value: $1.2 billion - 2015; $1.1 billion - 2014)	1,159,853	1,129,285
Federal Home Loan Bank (FHLB) stock	28,556	28,666
Loans – excluding covered assets, net of unearned fees	12,170,484	11,892,219
Allowance for loan losses	-156,610	-152,498
Loans, net of allowance for loan losses and unearned fees	12,013,874	11,739,721
Covered assets	32,191	34,132
Allowance for covered loan losses	-6,021	-5,191
Covered assets, net of allowance for covered loan losses	26,170	28,941
Other real estate owned, excluding covered assets	15,625	17,416
Premises, furniture, and equipment, net	38,544	39,143
Accrued interest receivable	41,202	40,531
Investment in bank owned life insurance	55,561	55,207
Goodwill	94,041	94,041
Other intangible assets	5,230	5,885
Derivative assets	56,607	43,062
Other assets	147,003	196,427
Total assets	16,361,348	15,603,382
Demand deposits:
Noninterest-bearing	3,936,181	3,516,695
Interest-bearing	1,498,810	1,907,320
Savings deposits and money market accounts	6,156,331	5,171,025
Time deposits	2,510,406	2,494,928
Total deposits	14,101,728	13,089,968
Deposits held-for-sale	0	122,216
Short-term and secured borrowings	258,788	432,385
Long-term debt	344,788	344,788
Accrued interest payable	7,004	6,948
Derivative liabilities	26,967	26,767
Other liabilities	82,644	98,631
Total liabilities	14,821,919	14,121,703
Equity
Common stock (no par value, $1 stated value; authorized shares: 174 million; issued shares: 78,654,425 - 2015 and 78,179,542 - 2014)	77,968	77,211
Treasury stock, at cost (160,193 - 2015 and 1,704 - 2014)	-5,560	-53
Additional paid-in capital	1,047,227	1,034,048
Retained earnings	390,247	349,556
Accumulated other comprehensive income, net of tax	29,547	20,917
Total equity	1,539,429	1,481,679
Total liabilities and equity	$16,361,348	$15,603,382

Consolidated_Statements_Of_Fin1

Consolidated Statements Of Financial Condition (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, except Share data, unless otherwise specified
Securities available-for-sale, pledged as collateral to creditors	$86,135	$86,527
Securities held-to-maturity, at fair value	$1,173,402	$1,132,615
Common Stock, Par or Stated Value Per Share	$1	$1
Common Stock, Shares Authorized	174,000,000	174,000,000
Common Stock, Shares, Issued	78,654,425	78,179,542
Treasury Stock, Shares	160,193	1,704

Consolidated_Statements_Of_Inc

Consolidated Statements Of Income (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Interest Income
Loans, including fees	$122,702	$110,199
Federal funds sold and interest-bearing deposits in banks	261	142
Securities:
Taxable	13,556	13,255
Exempt from Federal income taxes	1,806	1,529
Other interest income	48	33
Total interest income	138,373	125,158
Interest Expense
Interest-bearing demand deposits	1,006	942
Savings deposits and money market accounts	4,610	3,974
Time deposits	5,639	4,806
Short-term and secured borrowings	197	196
Long-term debt	4,928	6,488
Total interest expense	16,380	16,406
Net interest income	121,993	108,752
Provision for loan and covered loan losses	5,646	3,707
Net interest income after provision for loan and covered loan losses	116,347	105,045
Non-interest Income
Asset management	4,363	4,347
Mortgage banking	3,775	1,632
Capital markets products	4,172	4,083
Treasury management	7,327	6,599
Loan, letter of credit and commitment fees	5,106	4,634
Syndication fees	2,622	3,313
Deposit service charges and fees and other income	5,617	1,297
Net securities gains (losses)	534	331
Total non-interest income	33,516	26,236
Non-interest Expense
Salaries and employee benefits	52,361	44,620
Net occupancy and equipment expense	7,864	7,776
Technology and related costs	3,421	3,283
Marketing	3,578	2,413
Professional services	2,310	2,759
Outsourced servicing costs	1,680	1,464
Net foreclosed property expenses	1,328	2,823
Postage, telephone, and delivery	862	825
Insurance	3,211	2,903
Loan and collection expense	2,268	1,056
Other expenses	4,262	5,828
Total non-interest expense	83,145	75,750
Income (loss) before income taxes	66,718	55,531
Income tax provision	25,234	21,026
Net income (loss) available to common stockholders	$41,484	$34,505
Per Common Share Data
Basic earnings per share (in dollars)	$0.53	$0.44
Diluted earnings per share (in dollars)	$0.52	$0.44
Cash dividends declared (per share)	$0.01	$0.01
Weighted-average common shares outstanding	77,407	76,675
Weighted-average diluted common shares outstanding	78,512	77,417

Consolidated_Statements_Of_Com

Consolidated Statements Of Comprehensive Income (Unaudited) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Net income (loss)	$41,484	$34,505
Available-for-sale securities:
Net unrealized gains (losses)	8,590	3,677
Reclassification of net gains included in net income	-534	-331
Income tax expense	-3,148	-1,320
Net unrealized gains on available-for-sale securities	4,908	2,026
Cash flow hedges:
Net unrealized gains (losses)	8,630	4,137
Reclassification of net gains included in net income	-2,538	-2,043
Income tax expense	-2,370	-817
Net unrealized gains on cash flow hedges	3,722	1,277
Other comprehensive income	8,630	3,303
Comprehensive income	$50,114	$37,808

Consolidated_Statements_Of_Cha

Consolidated Statements Of Changes In Equity (Unaudited) (USD $)		Total	Common Shares Outstanding [Member]	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]		Accumulated Other Comprehensive Income [Member]
In Thousands, except Share data, unless otherwise specified		USD ($)		USD ($)	USD ($)	USD ($)	USD ($)		USD ($)
Beginning Balance at Dec. 31, 2013		$1,301,904		$76,825	($6,415)	$1,022,023	$199,627		$9,844
Beginning Balance (in shares) at Dec. 31, 2013			77,707,000
Comprehensive income (loss)
Net income (loss)		34,505					34,505	[1]
Other comprehensive income (loss)		3,303							3,303	[1]
Total comprehensive income (loss)	[1]	37,808
Cash dividends declared:
Cash dividends declared ($0.01 per common share)		-785				0	-785
Common stock issued for: [Abstract]
Nonvested (restricted) stock grants, shares			369,000
Nonvested (restricted) stock grants		0		-237	5,385	-5,148
Exercise of stock options, shares			109,000
Exercise of stock options		2,245		0	3,100	-855
Restricted stock activity, shares			5,000
Restricted stock activity		0		425	296	-721
Deferred compensation plan, shares			1,000
Deferred compensation plan		277		0	30	247
Excess tax benefit from share-based compensation plans		2,205				2,205
Stock repurchased in connection with share-based compensation plans, shares			-142,000
Stock repurchased in connection with share-based compensation plans		-4,093			-4,093
Share-based compensation expense		3,685				3,685
Ending Balance at Mar. 31, 2014		1,343,246		77,013	-1,697	1,021,436	233,347		13,147
Ending Balance (in shares) at Mar. 31, 2014			78,049,000
Beginning Balance at Dec. 31, 2014		1,481,679		77,211	-53	1,034,048	349,556		20,917
Beginning Balance (in shares) at Dec. 31, 2014			78,178,000
Comprehensive income (loss)
Net income (loss)		41,484					41,484	[1]
Other comprehensive income (loss)		8,630							8,630	[1]
Total comprehensive income (loss)	[1]	50,114
Cash dividends declared:
Cash dividends declared ($0.01 per common share)		-793					-793
Common stock issued for: [Abstract]
Nonvested (restricted) stock grants, shares			248,000
Nonvested (restricted) stock grants		0		0	0	0
Exercise of stock options, shares			235,000
Exercise of stock options		5,558		227	316	5,015
Restricted stock activity, shares			0
Restricted stock activity		0		530	0	-530
Deferred compensation plan, shares			1,000
Deferred compensation plan		146			22	124
Excess tax benefit from share-based compensation plans		3,427				3,427
Stock repurchased in connection with share-based compensation plans, shares			-168,000
Stock repurchased in connection with share-based compensation plans		-5,845			-5,845
Share-based compensation expense		5,143				5,143
Ending Balance at Mar. 31, 2015		$1,539,429		$77,968	($5,560)	$1,047,227	$390,247		$29,547
Ending Balance (in shares) at Mar. 31, 2015			78,494,000
[1]	Net of taxes and reclassification adjustments.

Consolidated_Statements_Of_Cas

Consolidated Statements Of Cash Flows (Unaudited) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Operating Activities
Net income (loss)	$41,484		$34,505
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Provision for loan and covered loan losses	5,646		3,707
Provision for unfunded commitments	376	[1]	496	[1]
Depreciation of premises, furniture, and equipment	2,163		2,052
Net amortization of premium on securities	4,044		3,503
Net (gains) losses on sale of securities	-534		-331
Valuation adjustment on other real estate owned	935		1,463
Net (gains) losses on sale of other real estate owned	227		317
Net amortization of discount on covered assets	141		259
Bank owned life insurance income	-354		-319
Net (decrease) increase in deferred loan fees	-155		-1,024
Share-based compensation expense	5,143		3,685
Excess tax benefit from exercise of stock options and vesting of restricted shares	-3,772		-2,340
Provision for deferred income tax expense	3,694		1,159
Amortization of other intangibles	655		756
Originations and purchases of loans held-for-sale	-166,370		-64,246
Proceeds from sales of loans held-for-sale	195,378		66,241
Net (gains) losses from sales of loans held-for-sale	-3,268		-1,259
Net (increase) decrease in derivative assets and liabilities	-13,345		-4,474
Net (increase) decrease in accrued interest receivable	-671		-2,269
Net (decrease) increase in accrued interest payable	56		-75
Net (increase) decrease in other assets	49,691		20,663
Net (decrease) increase in other liabilities	-12,285		-11,886
Net cash provided by (used in) operating activities	108,879		50,583
Available-for-sale securities:
Proceeds from maturities, prepayments, and calls	48,884		65,007
Proceeds from sales	28,931		47,477
Purchases	-57,733		-86,206
Held-to-maturity securities:
Proceeds from maturities, repayments, and calls	34,460		24,204
Purchases	-66,457		-127,016
Gain on sale of branch	-4,092
Net redemption (purchase) of FHLB stock	110		0
Net decrease (increase) in loans	-281,641		-280,419
Net decrease in covered assets	2,475		17,940
Proceeds from sale of other real estate owned	2,781		3,892
Net purchases of premises, furniture, and equipment	-1,564		-1,904
Net cash (used in) provided by investing activities	-293,846		-337,025
Financing Activities
Net (decrease) increase in deposit accounts	889,544		-127,480
Increase (decrease) in secured borrowings	1,403		0
Net increase (decrease) in FHLB advances	-175,000		325,000
Stock repurchased in connection with benefit plans	-5,845		-4,093
Cash dividends paid	-779		-778
Proceeds from exercise of stock options and issuance of common stock under benefit plans	5,704		2,522
Excess tax benefit from exercise of stock options and vesting of restricted shares	3,772		2,340
Net cash (used in) provided by financing activities	718,799		197,511
Net (decrease) increase in cash and cash equivalents	533,832		-88,931
Cash and cash equivalents at beginning of year	424,552		440,062
Cash and cash equivalents at end of period	958,384		351,131
Supplemental Disclosures of Cash Flow Information:
Cash paid for interest	16,324		16,482
Cash paid for income taxes	1,863		5,290
Non-cash transfer of loans to other real estate	2,152		689
Non-cash transfers of loans to loans held-for-sale	$50,630		$10,105
[1]	Unfunded commitments include commitments to extend credit, standby letters of credit and commercial letters of credit. Unfunded commitments related to covered assets are excluded as they are covered under a loss sharing agreement with the FDIC.

RECENT_ACCOUNTING_PRONOUNCEMEN

RECENT ACCOUNTING PRONOUNCEMENTS	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
RECENT ACCOUNTING PRONOUNCEMENTS	RECENT ACCOUNTING PRONOUNCEMENTS
	Recently Adopted Accounting Pronouncements
	Classification of Certain Government-Guaranteed Mortgage Loans upon Foreclosure - On January 1, 2015, we adopted new accounting guidance issued by the Financial Accounting Standards Board ("FASB") that requires a creditor to derecognize a mortgage loan upon foreclosure and recognize a separate other receivable if the following conditions are met: (1) the loan has a government guarantee that is not separable from the loan before foreclosure, (2) at the time of foreclosure, the creditor has the intent to convey the real estate property to the guarantor and make a claim on the guarantee, and the creditor has the ability to recover under that claim, and (3) at the time of foreclosure, any amount of the claim that is determined on the basis of the fair value of the real estate is fixed. Upon foreclosure, the separate other receivable is measured based on the amount of the loan balance expected to be recovered from the guarantor. The adoption of this guidance did not impact our financial position or consolidated results of operations.
	Reclassification of Residential Real Estate Collateralized Consumer Mortgage Loans - On January 1, 2015, we adopted new accounting guidance issued by the FASB that clarifies when an entity is considered to have received physical possession of residential real estate property collateralizing a consumer mortgage loan such that the loan receivable should be derecognized and the real estate property recognized. The guidance indicates that an in substance repossession or foreclosure occurs, and a creditor is considered to have received physical possession of residential real estate property collateralizing a consumer mortgage loan, upon either (1) the creditor obtaining legal title to the residential real estate property upon completion of a foreclosure or (2) the borrower conveying all interest in the residential real estate property to the creditor to satisfy that loan through completion of a deed in lieu of foreclosure or similar legal agreement. Additionally, the guidance requires disclosure of (1) the amount of foreclosed residential real estate property held by the Company and (2) the recorded investment in consumer mortgage loans collateralized by residential real estate property that are in the process of foreclosure. The adoption of this guidance did not impact our financial position or consolidated results of operations.
	Repurchase-to-Maturity Transactions, Repurchase Financings, and Disclosures - On January 1, 2015, we adopted new accounting guidance issued by the FASB that amends the accounting for repurchase-to-maturity transactions and repurchase financings, except for the disclosures related to transactions accounted for as secured borrowings, which will be effective for the Company’s financial statements that include periods beginning on April 1, 2015. Under the new guidance, repurchase-to-maturity transactions will be accounted for as secured borrowings. Additionally, the initial transfer and related repurchase agreement in a repurchase financing will need to be considered separately, rather than as a linked transaction. In addition, new disclosures will be required for (1) repurchase agreements, securities lending transactions, and repurchase-to-maturity transactions that are accounted for as secured borrowings, and (2) transfers accounted for as sales when the transferor also retains substantially all of the exposure to the economic return on the transferred financial assets throughout the term of the transaction. The adoption of this guidance did not impact our financial position or consolidated results of operations.
	Accounting Pronouncements Pending Adoption
	Revenue from Contracts with Customers - In May 2014, the FASB issued a comprehensive new revenue recognition standard that will replace most of the existing revenue recognition guidance in U.S. GAAP. All arrangements involving the transfer of goods or services to customers are within the scope of the guidance, except for certain contracts subject to other U.S. GAAP guidance, such as, including lease contracts and rights and obligations related to financial instruments. The standard’s core principle is that an entity should recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The guidance also includes new disclosure requirements related to the nature, timing, and uncertainty of revenue and cash flows arising from contracts with customers. The guidance will be effective for the Company’s financial statements beginning January 1, 2017. The Company may choose to apply the new standard either retrospectively or through a cumulative effect adjustment as of January 1, 2017. The Company is in the process of determining the effect of the new guidance on our financial position and consolidated results of operations, as well as which transition method to use.
	Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period - In June 2014, the FASB issued guidance that clarifies the accounting for a performance target that affects vesting of a share-based payment award and that could be achieved after the requisite service period. The guidance indicates that such a performance target would not be reflected in the estimation of the award’s grant date fair value. Rather, compensation cost for such an award would be recognized over the requisite service period, if it is probable that the performance target will be achieved. The total amount of compensation cost recognized during and after the requisite service period would reflect the number of awards that are expected to vest and would be adjusted to reflect those awards that ultimately vest. The guidance will be effective for the Company’s financial statements that include periods beginning January 1, 2016 and applied prospectively to awards that are granted or modified after the effective date. The adoption of this guidance is not expected to have a material impact on our financial position or consolidated results of operations.
	Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern - In August 2014, the FASB issued guidance that requires management to evaluate whether there are conditions and events that raise substantial doubt about an entity’s ability to continue as a going concern. The guidance requires new disclosures to the extent management concludes there is substantial doubt about an entity’s ability to continue as a going concern. The guidance will be effective for the Company’s annual financial statements dated December 31, 2016, as well as interim periods thereafter. The adoption of this guidance is not expected to have a material impact on our financial position or consolidated results of operations.
	Amendments to the Consolidation Analysis- In February 2015, the FASB issued guidance that changes certain aspects of the variable interest and voting interest consolidation models. The amendments modify existing guidance on (1) the evaluation of whether limited partnerships and similar legal entities are variable interest entities (“VIEs”) or voting interest entities, (2) when fee arrangements represent variable interests in a VIE, and (3) the primary beneficiary determination for VIEs. Additionally, the guidance eliminates the presumption that a general partner controls a limited partnership under the voting interest model and exempts reporting entities from consolidating money market funds that are required to comply with or operate in accordance with requirements that are similar to those in Rule 2a-7 of the Investment Company Act of 1940. The guidance will be effective for the Company’s financial statements that include periods beginning on January 1, 2016. The Company may choose to apply the guidance either retrospectively or through a cumulative effect adjustment as of January 1, 2016. The Company is in the process of determining the effect of the new guidance on our financial position and consolidated results of operations, as well as which transition method to use.

SUMMARY_OF_SIGNIFICANT_ACCOUNT

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
	The accompanying unaudited consolidated interim financial statements of PrivateBancorp, Inc. ("PrivateBancorp" or the "Company"), a Delaware corporation, have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission for quarterly reports on Form 10-Q and do not include certain information and footnote disclosures required by U.S. generally accepted accounting principles ("U.S. GAAP") for complete annual financial statements. Accordingly, these financial statements should be read in conjunction with the Company’s Annual Report on Form 10-K for our fiscal year ended December 31, 2014.
	The accompanying unaudited consolidated interim financial statements have been prepared in accordance with U.S. GAAP and reflect all adjustments that are, in the opinion of management, necessary for the fair presentation of the financial position and results of operations for the periods presented. All such adjustments are of a normal recurring nature. The results of operations for interim periods are not necessarily indicative of the results that may be expected for the year or any other period.
	The accompanying consolidated financial statements include the accounts and results of operations of the Company and its subsidiary, The PrivateBank and Trust Company (the "Bank"), after elimination of all significant intercompany accounts and transactions. Certain reclassifications have been made to prior period amounts to conform to the current period presentation. The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make certain estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from these estimates.
	In preparing the consolidated financial statements, we have considered the impact of events occurring subsequent to March 31, 2015 for potential recognition or disclosure.

SECURITIES

SECURITIES	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
SECURITIES	SECURITIES
	Securities Portfolio
	(Amounts in thousands)
		31-Mar-15												31-Dec-14
		Amortized Cost			Gross Unrealized						Fair Value			Amortized Cost		Gross Unrealized						Fair Value
					Gains			Losses								Gains			Losses
	Securities Available-for-Sale
	U.S. Treasury	$	243,608		$	1,186		$	(238	)	$	244,556		$	269,697	$	120		$	(1,552	)	$	268,265
	U.S. Agency	46,847			20			(61		)	46,806			46,959		—			(701		)	46,258
	Collateralized mortgage obligations	123,181			4,647			—			127,828			132,633		4,334			(34		)	136,933
	Residential mortgage-backed securities	802,921			27,797			(1,305		)	829,413			822,746		25,058			(1,726		)	846,078
	State and municipal securities	374,125			8,521			(512		)	382,134			340,810		7,222			(722		)	347,310
	Foreign sovereign debt	500			—			—			500			500		—			—			500
	Total	$	1,591,182		$	42,171		$	(2,116	)	$	1,631,237		$	1,613,345	$	36,734		$	(4,735	)	$	1,645,344
	Securities Held-to-Maturity
	Collateralized mortgage obligations	$	58,209		$	—		$	(1,273	)	$	56,936		$	59,960	$	—		$	(2,017	)	$	57,943
	Residential mortgage-backed securities	909,643			15,195			(1,470		)	923,368			885,235		9,410			(2,483		)	892,162
	Commercial mortgage-backed securities	190,932			1,710			(618		)	192,024			183,021		592			(2,176		)	181,437
	State and municipal securities	1,069			5			—			1,074			1,069		4			—			1,073
	Total	$	1,159,853		$	16,910		$	(3,361	)	$	1,173,402		$	1,129,285	$	10,006		$	(6,676	)	$	1,132,615
	The carrying value of securities pledged to secure public deposits, FHLB advances, trust deposits, Federal Reserve Bank ("FRB") discount window borrowing availability, derivative transactions, standby letters of credit with counterparty banks and for other purposes as permitted or required by law, totaled $383.5 million and $353.1 million at March 31, 2015 and December 31, 2014, respectively. Of total pledged securities, securities pledged to creditors under agreements pursuant to which the collateral may be sold or re-pledged by the secured parties totaled $86.1 million and $86.5 million at March 31, 2015 and December 31, 2014, respectively.
	Excluding securities issued or backed by the U.S. Government and its agencies and U.S. Government-sponsored enterprises, there were no investments in securities from one issuer that exceeded 10% of consolidated equity at March 31, 2015 or December 31, 2014.
	The following table presents the fair values of securities with unrealized losses as of March 31, 2015 and December 31, 2014. The securities presented are grouped according to the time periods during which the securities have been in a continuous unrealized loss position.
	Securities in Unrealized Loss Position
	(Amounts in thousands)
		Less Than 12 Months						12 Months or Longer						Total
		Fair			Unrealized			Fair			Unrealized			Fair		Unrealized
		Value			Losses			Value			Losses			Value		Losses
	As of March 31, 2015
	Securities Available-for-Sale
	U.S. Treasury	$	25,187		$	(46	)	$	52,348		$	(192	)	$	77,535	$	(238	)
	U.S. Agency	14,875			(61		)	—			—			14,875		(61		)
	Residential mortgage-backed securities	2,577			(6		)	86,266			(1,299		)	88,843		(1,305		)
	State and municipal securities	63,470			(441		)	4,623			(71		)	68,093		(512		)
	Total	$	106,109		$	(554	)	$	143,237		$	(1,562	)	$	249,346	$	(2,116	)
	Securities Held-to-Maturity
	Collateralized mortgage obligations	$	—		$	—		$	56,936		$	(1,273	)	$	56,936	$	(1,273	)
	Residential mortgage-backed securities	118,201			(643		)	64,950			(827		)	183,151		(1,470		)
	Commercial mortgage-backed securities	24,076			(124		)	50,056			(494		)	74,132		(618		)
	Total	$	142,277		$	(767	)	$	171,942		$	(2,594	)	$	314,219	$	(3,361	)
	As of December 31, 2014
	Securities Available-for-Sale
	U.S. Treasury	$	119,233		$	(159	)	$	123,117		$	(1,393	)	$	242,350	$	(1,552	)
	U.S. Agency	—			—			46,258			(701		)	46,258		(701		)
	Collateralized mortgage obligations	4,565			(34		)	—			—			4,565		(34		)
	Residential mortgage-backed securities	—			—			89,085			(1,726		)	89,085		(1,726		)
	State and municipal securities	53,092			(249		)	32,152			(473		)	85,244		(722		)
	Total	$	176,890		$	(442	)	$	290,612		$	(4,293	)	$	467,502	$	(4,735	)
	Securities Held-to-Maturity
	Collateralized mortgage obligations	$	—		$	—		$	57,943		$	(2,017	)	$	57,943	$	(2,017	)
	Residential mortgage-backed securities	45,867			(38		)	162,564			(2,445		)	208,431		(2,483		)
	Commercial mortgage-backed securities	10,021			(28		)	105,709			(2,148		)	115,730		(2,176		)
	Total	$	55,888		$	(66	)	$	326,216		$	(6,610	)	$	382,104	$	(6,676	)
	There were $315.2 million of securities with $4.2 million in an unrealized loss position for greater than 12 months at March 31, 2015. At December 31, 2014, there were $616.8 million of securities with $10.9 million in an unrealized loss position for greater than 12 months. The Company does not consider these unrealized losses to be credit-related. These unrealized losses relate to changes in interest rates and market spreads. We do not intend to sell the securities nor do we believe it is more likely than not that we will be required to sell the investments before recovery of their amortized cost bases, which may be at maturity. Accordingly, no other-than-temporary impairments have been recorded on these securities during the quarter ended March 31, 2015 or during 2014.
	The following table presents the remaining contractual maturity of securities as of March 31, 2015 by amortized cost and fair value.
	Remaining Contractual Maturity of Securities
	(Amounts in thousands)
		31-Mar-15
		Available-For-Sale Securities						Held-To-Maturity Securities
		Amortized			Fair			Amortized			Fair
		Cost			Value			Cost			Value
	U.S. Treasury, U.S. Agency, state and municipal and foreign sovereign debt securities:
	One year or less	$	7,839		$	7,985		$	816		$	817
	One year to five years	447,192			452,133			253			257
Five years to ten years	195,714			199,318			—			—
After ten years	14,335			14,560			—			—
All other securities:
Collateralized mortgage obligations	123,181			127,828			58,209			56,936
Residential mortgage-backed securities	802,921			829,413			909,643			923,368
Commercial mortgage-backed securities	—			—			190,932			192,024
Total	$	1,591,182		$	1,631,237		$	1,159,853		$	1,173,402
The following table presents gains (losses) on securities for the quarters ended March 31, 2015 and 2014.
Securities Gains (Losses)
(Amounts in thousands)
	Quarter Ended March 31,
	2015			2014
Proceeds from sales	$	28,931		$	47,477
Gross realized gains	$	538		$	397
Gross realized losses	(4		)	(66		)
Net realized gains	$	534		$	331
Income tax provision on net realized gains	$	210		$	131
Refer to Note 10 for additional details of the securities available-for-sale portfolio and the related impact of unrealized gains (losses) on other comprehensive income.

LOANS_AND_CREDIT_QUALITY

LOANS AND CREDIT QUALITY	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
LOANS	LOANS AND CREDIT QUALITY
	The following loan portfolio and credit quality disclosures exclude covered loans. Covered loans represent loans acquired through a Federal Deposit Insurance Corporation ("FDIC") assisted transaction that are subject to a loss share agreement and are presented separately in the Consolidated Statements of Financial Condition. Refer to the "Covered Assets" section in this footnote for a detailed discussion regarding covered loans.
	Loan Portfolio
	(Amounts in thousands)
		March 31,				December 31,
		2015				2014
	Commercial and industrial	$	6,213,029			$	5,996,070
	Commercial - owner-occupied CRE	1,977,601				1,892,564
	Total commercial	8,190,630				7,888,634
	Commercial real estate	2,411,359				2,323,616
	Commercial real estate - multi-family	492,695				593,103
	Total commercial real estate	2,904,054				2,916,719
	Construction	357,258				381,102
	Residential real estate	376,741				361,565
	Home equity	138,734				142,177
	Personal	203,067				202,022
	Total loans	$	12,170,484			$	11,892,219
	Net deferred loan fees and unamortized discount and premium on loans, included as a reduction in total loans	$	46,862			$	47,017
	Overdrawn demand deposits included in total loans	$	1,540			$	1,963
	We primarily lend to businesses and consumers in the market areas in which we have physical locations. We seek to diversify our loan portfolio by loan type, industry, and borrower.
	Loans Held-For-Sale
	(Amounts in thousands)
		March 31,				December 31,
		2015				2014
	Mortgage loans held-for-sale (1)	$	21,866			$	42,215
	Other loans held-for-sale (2)	67,595				72,946
	Total loans held-for-sale	$	89,461			$	115,161
	(1)	Comprised of residential mortgage loan originations intended to be sold in the secondary market. The Company accounts for these loans under the fair value option. Refer to Note 16 for additional information regarding mortgage loans held-for-sale.
	(2)	Amounts at March 31, 2015 represent commercial, commercial real estate, and construction loans carried at the lower of aggregate cost or fair value. Generally, the Company intends to sell these loans within 30-60 days from the date the intent to sell was established. Amounts at December 31, 2014 consists of $36.6 million of commercial, commercial real estate and construction loans carried at the lower of aggregate cost or fair value and $36.3 million of commercial, commercial real estate, construction, home equity and personal loans held-for-sale in connection with the sale of the Company's banking office located in Norcross, Georgia, which closed in January 2015.
	Carrying Value of Loans Pledged
	(Amounts in thousands)
		March 31,				December 31,
		2015				2014
	Loans pledged to secure outstanding borrowings or availability:
	FRB discount window borrowings (1)	$	458,615			$	478,692
	FHLB advances (2)	1,851,727				1,576,168
	Total	$	2,310,342			$	2,054,860
	(1)	No borrowings were outstanding at March 31, 2015 or December 31, 2014.
	(2)	Refer to Notes 7 and 8 for additional information regarding FHLB advances.
	Loan Portfolio Aging
	(Amounts in thousands)
						Delinquent
		Current				30 – 59				60 – 89			90 Days Past				Total				Nonaccrual			Total Loans
						Days Past Due				Days Past Due			Due and				Accruing
													Accruing				Loans
	As of March 31, 2015
	Commercial	$	8,147,503			$	1,862			$	2,292		$	—			$	8,151,657			$	38,973		$	8,190,630
	Commercial real estate	2,888,347				88				—			—				2,888,435				15,619			2,904,054
	Construction	356,308				950				—			—				357,258				—			357,258
	Residential real estate	368,824				2,912				242			—				371,978				4,763			376,741
	Home equity	126,575				814				—			—				127,389				11,345			138,734
	Personal	202,692				47				10			—				202,749				318			203,067
	Total loans	$	12,090,249			$	6,673			$	2,544		$	—			$	12,099,466			$	71,018		$	12,170,484
	As of December 31, 2014
	Commercial	$	7,855,833			$	762			$	992		$	—			$	7,857,587			$	31,047		$	7,888,634
	Commercial real estate	2,891,301				5,408				261			—				2,896,970				19,749			2,916,719
	Construction	380,939				163				—			—				381,102				—			381,102
	Residential real estate	354,717				943				631			—				356,291				5,274			361,565
	Home equity	128,500				397				2,236			—				131,133				11,044			142,177
	Personal	201,569				23				—			—				201,592				430			202,022
	Total loans	$	11,812,859			$	7,696			$	4,120		$	—			$	11,824,675			$	67,544		$	11,892,219
	Impaired Loans
	Impaired loans consist of nonaccrual loans (which include nonaccrual troubled debt restructurings ("TDRs")) and loans classified as accruing TDRs. A loan is considered impaired when, based on current information and events, either (i) management believes that it is probable that we will be unable to collect all amounts due (both principal and interest) according to the original contractual terms of the loan agreement, or (ii) it has been classified as a TDR.
	The following two tables present our recorded investment in impaired loans outstanding by product segment, including our recorded investment in impaired loans, which represents the principal amount outstanding, net of unearned income, deferred loan fees and costs, and any direct principal charge-offs.
Impaired Loans
(Amounts in thousands)
	Unpaid				Recorded				Recorded			Total				Specific
	Contractual				Investment				Investment			Recorded				Reserve
	Principal				With No				With			Investment
	Balance				Specific				Specific
					Reserve				Reserve
As of March 31, 2015
Commercial	$	70,501			$	31,582			$	28,166		$	59,748			$	10,643
Commercial real estate	22,385				6,020				9,776			15,796				2,201
Residential real estate	5,344				—				4,763			4,763				430
Home equity	13,425				3,651				9,110			12,761				2,292
Personal	318				—				318			318				70
Total impaired loans	$	111,973			$	41,253			$	52,133		$	93,386			$	15,636
As of December 31, 2014
Commercial	$	60,174			$	25,739			$	26,432		$	52,171			$	11,487
Commercial real estate	26,738				9,755				10,193			19,948				2,441
Residential real estate	5,849				349				4,925			5,274				735
Home equity	12,904				3,627				8,839			12,466				1,855
Personal	430				—				430			430				109
Total impaired loans	$	106,095			$	39,470			$	50,819		$	90,289			$	16,627
Average Recorded Investment and Interest Income Recognized on Impaired Loans (1)
(Amounts in thousands)
	Quarter Ended March 31,
	2015								2014
	Average				Interest				Average			Interest
	Recorded				Income				Recorded			Income
	Investment				Recognized				Investment			Recognized
Commercial	$	53,048			$	184			$	43,777		$	382
Commercial real estate	17,897				3				46,415			24
Residential real estate	4,979				—				9,833			—
Home equity	13,332				22				13,526			24
Personal	356				—				663			—
Total	$	89,612			$	209			$	114,214		$	430
(1)	Represents amounts while classified as impaired for the periods presented.
Credit Quality Indicators
We have adopted an internal risk rating policy in which each loan is rated for credit quality with a numerical rating of 1 through 8. Loans rated 5 and better (1-5 ratings, inclusive) are credits that we believe exhibit acceptable financial performance, cash flow, and leverage. We attempt to mitigate risk through loan structure, collateral, monitoring, and other credit risk management controls. Credits rated 6 are performing in accordance with contractual terms but are considered "special mention" as these credits demonstrate potential weakness that if left unresolved, may result in deterioration in our credit position and/or the repayment prospects for the credit. Borrowers rated special mention may exhibit adverse operating trends, high leverage, tight liquidity or other credit concerns. Loans rated 7 may be classified as either accruing ("potential problem") or nonaccrual ("nonperforming"). Potential problem loans, like special mention, are loans that are performing in accordance with contractual terms, but for which management has some level of concern (greater than that of special mention loans) about the ability of the borrowers to meet existing repayment terms in future periods. These loans continue to accrue interest but the ultimate collection of these loans in full is questionable due to the same conditions that characterize a 6-rated credit. These credits may also have somewhat increased risk profiles as a result of the current net worth and/or paying capacity of the obligor or guarantors or the value of the collateral pledged. These loans generally have a well-defined weakness that may jeopardize collection of the debt and are characterized by the distinct possibility that we may sustain some loss if the deficiencies are not resolved. Although these loans are generally identified as potential problem loans and require additional attention by management, they may never become nonperforming. Nonperforming loans include nonaccrual loans risk rated 7 or 8 and have all the weaknesses inherent in a 7-rated potential problem loan with the added characteristic that the weaknesses make collection or liquidation in full, on the basis of currently-existing facts, conditions and values, highly questionable and improbable. Special mention, potential problem and nonperforming loans are reviewed at a minimum on a quarterly basis, while all other rated credits over a certain dollar threshold, depending on loan type, are reviewed annually or more frequently as the circumstances warrant.
Credit Quality Indicators
(Dollars in thousands)
	Special				% of			Potential			% of			Non-				% of			Total Loans
	Mention				Portfolio			Problem			Portfolio			Performing				Portfolio
					Loan			Loans			Loan			Loans				Loan
					Type						Type							Type
As of March 31, 2015
Commercial	$	97,851			1.2			$	95,448		1.2			$	38,973			0.5			$	8,190,630
Commercial real estate	130				*			2,925			0.1			15,619				0.5			2,904,054
Construction	—				—			—			—			—				—			357,258
Residential real estate	3,323				0.9			6,045			1.6			4,763				1.3			376,741
Home equity	502				0.4			2,599			1.9			11,345				8.2			138,734
Personal	845				0.4			21			*			318				0.2			203,067
Total	$	102,651			0.8			$	107,038		0.9			$	71,018			0.6			$	12,170,484
As of December 31, 2014
Commercial	$	93,130			1.2			$	78,562		1			$	31,047			0.4			$	7,888,634
Commercial real estate	3,552				0.1			746			*			19,749				0.7			2,916,719
Construction	—				—			—			—			—				—			381,102
Residential real estate	2,964				0.8			5,981			1.7			5,274				1.5			361,565
Home equity	1,170				0.8			2,108			1.5			11,044				7.8			142,177
Personal	173				0.1			45			*			430				0.2			202,022
Total	$	100,989			0.8			$	87,442		0.7			$	67,544			0.6			$	11,892,219
*	Less than 0.1%
Troubled Debt Restructured Loans
Troubled Debt Restructured Loans Outstanding
(Amounts in thousands)
	31-Mar-15								31-Dec-14
	Accruing				Nonaccrual (1)				Accruing			Nonaccrual (1)
Commercial	$	20,775			$	17,333			$	21,124		$	20,113
Commercial real estate	177				12,335				199			8,005
Residential real estate	—				1,737				—			1,881
Home equity	1,416				5,701				1,422			5,886
Personal	—				284				—			413
Total	$	22,368			$	37,390			$	22,745		$	36,298
(1)	Included in nonperforming loans.
At March 31, 2015 and December 31, 2014, credit commitments to lend additional funds to debtors whose loan terms have been modified in a TDR (both accruing and nonaccruing) totaled $5.5 million and $8.5 million, respectively.
Additions to Troubled Debt Restructurings During the Period
(Dollars in thousands)
	Quarter Ended March 31,
	2015										2014
	Number of			Recorded Investment (1)							Number of			Recorded Investment (1)
	Borrowers			Pre-				Post-			Borrowers			Pre-				Post-
				Modification				Modification						Modification				Modification
Accruing TDRs
Commercial
Extension of maturity date (2)	1			$	2,394			$	2,394		1			$	200			$	200
Other concession (3)	—			—				—			1			12,941				12,941
Total commercial	1			2,394				2,394			2			13,141				13,141
Commercial real estate
Other concession (3)	—			—				—			1			426				426
Total accruing	1			$	2,394			$	2,394		3			$	13,567			$	13,567
Nonaccrual TDRs
Commercial
Other concession (3)	1			$	673			$	666		2			$	456			$	406
Commercial real estate
Extension of maturity date (2)	2			1,747				1,660			—			—				—
Other concession (3)	1			3,773				3,773			—			—				—
Total commercial real estate	3			5,520				5,433			—			—				—
Residential real estate
Other concession (3)	—			—				—			2			495				495
Home equity
Extension of maturity date (2)	—			—				—			1			114				114
Other concession (3)	2			77				77			1			250				250
Total home equity	2			77				77			2			364				364
Total nonaccrual	6			$	6,270			$	6,176		6			$	1,315			$	1,265
Change in recorded investment due to principal paydown at time of modification								$	94									$	50
(1)	Represents amounts as of the date immediately prior to and immediately after the modification is effective.
(2)	Extension of maturity date also includes loans renewed at existing rate of interest which is considered a below market rate for that particular loan’s risk profile.
(3)	Other concessions primarily include interest rate reductions, loan increases or deferrals of principal.
At the time an accruing loan becomes modified and meets the definition of a TDR, it is considered impaired and no longer included as part of the general loan loss reserve calculation. However, our general reserve methodology considers the amount and product type of the TDRs removed as a proxy for potentially heightened risk in the portfolio when establishing final reserve requirements.
As impaired loans, TDRs (both accruing and nonaccruing) are evaluated for impairment at the end of each quarter with a specific valuation reserve created, or adjusted (either individually or as part of a pool), if necessary, as a component of the allowance for loan losses. Refer to the "Impaired Loan" and "Allowance for Loan Loss" sections of Note 1, "Summary of Significant Accounting Policies," to the Notes to Consolidated Financial Statements of our 2014 Annual Report on Form 10-K regarding our policy for assessing potential impairment on such loans. Our allowance for loan losses included $9.9 million and $10.6 million in specific reserves for nonaccrual TDRs at March 31, 2015 and December 31, 2014, respectively. For accruing TDRs, there were no specific reserves at March 31, 2015 and December 31, 2014, respectively, as the present value of cash flows for the restructured loan were greater than the recorded investment in the loan.
During the three months ended March 31, 2014, a single commercial real estate loan totaling $699,000 became nonperforming within 12 months of being modified as an accruing TDR. There were no such transactions for the three months ended March 31, 2015. A loan becomes nonperforming and placed on nonaccrual status typically when the principal or interest payments are 90 days past due based on contractual terms or when an individual analysis of a borrower’s creditworthiness indicates a loan should be placed on nonaccrual status earlier than when the loan becomes 90 days past due.
Other Real Estate Owned
The following table presents the composition of property by type acquired as a result of borrower defaults on loans secured by real property.
OREO Composition
(Amounts in thousands)
	31-Mar-15				31-Dec-14
Single-family homes	$	7,698			$	7,902
Land parcels	3,971				4,237
Multi-family	465				488
Office/industrial	2,663				3,832
Retail	828				957
Total OREO properties	$	15,625			$	17,416
The recorded investment of consumer mortgage loans secured by residential real estate properties for which foreclosure proceedings are in process totaled $4.8 million at March 31, 2015 and $5.5 million December 31, 2014, respectively.
Covered Assets
Covered assets represent acquired residential mortgage loans and foreclosed loan collateral covered under a loss sharing agreement with the FDIC and include an indemnification receivable representing the present value of the expected reimbursement from the FDIC related to expected losses on the acquired loans and foreclosed real estate under such agreement. The loss share agreement will expire on September 30, 2019.
The carrying amount of covered assets is presented in the following table.
Covered Assets
(Amounts in thousands)
	March 31, 2015				December 31, 2014
Residential mortgage loans (1)	$	29,963			$	32,182
Foreclosed real estate - single family homes	203				187
Estimated loss reimbursement by the FDIC	2,025				1,763
Total covered assets	32,191				34,132
Allowance for covered loan losses	(6,021		)		(5,191		)
Net covered assets	$	26,170			$	28,941
(1)	Includes $266,000 and $420,000 of purchased impaired loans as of March 31, 2015 and December 31, 2014, respectively.
The recorded investment of residential real estate properties for which foreclosure proceedings are in process totaled $635,000 and $856,000 at March 31, 2015 and December 31, 2014, respectively.

ALLOWANCE_FOR_LOAN_LOSSES_AND_

ALLOWANCE FOR LOAN LOSSES AND RESERVE FOR UNFUNDED COMMITMENTS	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
ALLOWANCE FOR LOAN LOSSES AND RESERVE FOR UNFUNDED COMMITMENTS	ALLOWANCE FOR LOAN LOSSES AND RESERVE FOR UNFUNDED COMMITMENTS																						[1]
	The following allowance and credit quality disclosures exclude covered loans. Refer to Note 4 for a discussion regarding covered loans.
	Allowance for Loan Losses and Recorded Investment in Loans
	(Amounts in thousands)
		Quarter Ended March 31, 2015
		Commercial			Commercial			Construction			Residential			Home			Personal			Total
					Real						Real			Equity
					Estate						Estate
	Allowance for Loan Losses:
	Balance at beginning of period	$	103,462		$	31,838		$	4,290		$	5,316		$	4,924		$	2,668		$	152,498
	Loans charged-off	(2,202		)	(887		)	—			(37		)	(371		)	(10		)	(3,507		)
	Recoveries on loans previously charged-off	511			598			19			57			70			873			2,128
	Net (charge-offs) recoveries	(1,691		)	(289		)	19			20			(301		)	863			(1,379		)
	Provision (release) for loan losses	7,102			57			(283		)	(113		)	(35		)	(1,237		)	5,491
	Balance at end of period	$	108,873		$	31,606		$	4,026		$	5,223		$	4,588		$	2,294		$	156,610
	Ending balance, loans individually evaluated for impairment (1)	$	10,643		$	2,201		$	—		$	430		$	2,292		$	70		$	15,636
	Ending balance, loans collectively evaluated for impairment	$	98,230		$	29,405		$	4,026		$	4,793		$	2,296		$	2,224		$	140,974
	Recorded Investment in Loans:
	Ending balance, loans individually evaluated for impairment (1)	$	59,748		$	15,796		$	—		$	4,763		$	12,761		$	318		$	93,386
	Ending balance, loans collectively evaluated for impairment	8,130,882			2,888,258			357,258			371,978			125,973			202,749			12,077,098
	Total recorded investment in loans	$	8,190,630		$	2,904,054		$	357,258		$	376,741		$	138,734		$	203,067		$	12,170,484
	(1)	Refer to Note 4 for additional information regarding impaired loans.
	Allowance for Loan Losses and Recorded Investment in Loans (Continued)
	(Amounts in thousands)
		Quarter Ended March 31, 2014
		Commercial			Commercial			Construction			Residential			Home			Personal			Total
					Real						Real			Equity
					Estate						Estate
	Allowance for Loan Losses:
	Balance at beginning of period	$	80,768		$	42,362		$	3,338		$	7,555		$	5,648		$	3,438		$	143,109
	Loans charged-off	(1,487		)	(2,582		)	—			(235		)	(447		)	(130		)	(4,881		)
	Recoveries on loans previously charged-off	3,662			688			7			300			28			406			5,091
	Net recoveries (charge-offs)	2,175			(1,894		)	7			65			(419		)	276			210
	Provision (release) for loan losses	7,137			(2,893		)	202			(642		)	271			(626		)	3,449
	Balance at end of period	$	90,080		$	37,575		$	3,547		$	6,978		$	5,500		$	3,088		$	146,768
	Ending balance, loans individually evaluated for impairment (1)	$	8,678		$	9,479		$	—		$	2,198		$	2,274		$	138		$	22,767
	Ending balance, loans collectively evaluated for impairment	$	81,402		$	28,096		$	3,547		$	4,780		$	3,226		$	2,950		$	124,001
	Recorded Investment in Loans:
	Ending balance, loans individually evaluated for impairment (1)	$	54,700		$	42,180		$	—		$	9,354		$	13,430		$	625		$	120,289
	Ending balance, loans collectively evaluated for impairment	7,342,248			2,457,226			335,476			328,478			134,144			207,124			10,804,696
	Total recorded investment in loans	$	7,396,948		$	2,499,406		$	335,476		$	337,832		$	147,574		$	207,749		$	10,924,985
	(1)	Refer to Note 4 for additional information regarding impaired loans.
	Reserve for Unfunded Commitments (1)
	(Amounts in thousands)
		Quarter Ended March 31,
		2015			2014
	Balance at beginning of period	$	12,274		$	9,206
	Provision for unfunded commitments	376			496
	Balance at end of period	$	12,650		$	9,702
	Unfunded commitments, excluding covered assets, at period end	$	6,229,242		$	4,814,346
	(1)	Unfunded commitments include commitments to extend credit, standby letters of credit and commercial letters of credit. Unfunded commitments related to covered assets are excluded as they are covered under a loss sharing agreement with the FDIC.
	Refer to Note 14 for additional details of commitments to extend credit, standby letters of credit and commercial letters of credit.
[1]	Refer to Note 4 for additional information regarding impaired loans.

GOODWILL_AND_OTHER_INTANGIBLE_

GOODWILL AND OTHER INTANGIBLE ASSETS	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
GOODWILL AND OTHER INTANGIBLE ASSETS	GOODWILL AND OTHER INTANGIBLE ASSETS
	Carrying Amount of Goodwill by Operating Segment
	(Amounts in thousands)
		March 31,		31-Dec-14
		2015
	Banking	$	81,755	$	81,755
	Asset management	12,286		12,286
	Total goodwill	$	94,041	$	94,041
	Goodwill is not amortized but, instead, is subject to impairment tests at least on an annual basis or more often if events or circumstances occur that would indicate it is more likely than not that the fair value of a reporting unit is below its carrying value. Our annual goodwill impairment test was performed as of October 31, 2014, and it was determined no impairment existed as of that date nor are we aware of any events or circumstances subsequent to October 31, 2014 that would indicate impairment of goodwill at March 31, 2015. There were no impairment charges for goodwill recorded in 2014. Our annual goodwill test will be completed during the fourth quarter 2015.
	We have other intangible assets capitalized on the Consolidated Statements of Financial Condition in the form of core deposit premiums and client relationships. These intangible assets are being amortized over their estimated useful lives, which range from 8 to 12 years.
	We review intangible assets for possible impairment whenever events or changes in circumstances indicate that carrying amounts may not be recoverable. During the first quarter 2015, there were no events or circumstances that we believe indicate there may be impairment of intangible assets, and no impairment charges for other intangible assets were recorded for the quarter ended March 31, 2015.
	Other Intangible Assets
	(Dollars in thousands)
		Quarter Ended March 31, 2015		Year Ended December 31, 2014
	Core deposit intangibles:
	Gross carrying amount	$	18,093	$	18,093
	Accumulated amortization	13,473		12,870
	Net carrying amount	$	4,620	$	5,223
	Amortization during the period	$	603	$	2,799
	Weighted average remaining life (in years)	2		2
	Client relationships:
	Gross carrying amount	$	2,002	$	2,002
	Accumulated amortization	1,392		1,340
	Net carrying amount	$	610	$	662
	Amortization during the period	$	52	$	208
	Weighted average remaining life (in years)	6		6
	Scheduled Amortization of Other Intangible Assets
	(Amounts in thousands)
		Total
	Year ending December 31,
	2015 - remaining nine months	$	1,800
	2016	2,161
	2017	1,125
	2018	98
	2019	28
	2020 and thereafter	18
	Total	$	5,230

SHORTTERM_AND_SECURED_BORROWIN

SHORT-TERM AND SECURED BORROWINGS	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
SHORT-TERM AND SECURED BORROWINGS	SHORT-TERM AND SECURED BORROWINGS
	Summary of Short-Term Borrowings
	(Dollars in thousands)
		31-Mar-15				31-Dec-14
		Amount		Rate		Amount		Rate
	Outstanding:
	FHLB advances	$	253,000	0.14	%	$	428,000	0.13	%
	Other borrowings	33		0.06	%	—		—	%
	Total short-term borrowings	$	253,033			$	428,000
	Other Information:
	Weighted average remaining maturity of FHLB advances at period end	9 months				7 months
	Unused FHLB advances availability	$	552,721			$	265,529
	Unused overnight Federal funds availability (1)	$	630,500			$	630,500
	Borrowing capacity through the FRB discount window primary credit program (2)	$	392,842			$	403,752
	(1)	Our total availability of overnight Federal fund borrowings is not a committed line of credit and is dependent upon lender availability.
	(2)	Our borrowing capacity changes each quarter subject to available collateral and FRB discount factors.
	Borrowings with maturities of one year or less are classified as short-term and include FHLB advances and other borrowings.
	FHLB Advances - At March 31, 2015, FHLB advances consisted of $8.0 million from the FHLB Atlanta, of which $3.0 million is included in short-term borrowings, and $295.0 million from FHLB Chicago, of which $250.0 million is included in short-term borrowings. As a member of the FHLB Chicago, the Bank has access to borrowing capacity which is subject to change based on the availability of acceptable collateral to pledge and the level of our investment in FHLB Chicago stock. At March 31, 2015 our borrowing capacity was $848.1 million of which $552.7 million is available, subject to making the required additional investment in FHLB Chicago stock. Qualifying residential, multi-family and commercial real estate loans, home equity lines of credit, and residential mortgage-backed securities are pledged as collateral to secure current outstanding balances and additional borrowing availability.
	Other Borrowings - Other borrowings represents cash received by counterparty in excess of derivative liability at March 31, 2015.
	Revolving Line of Credit - The Company has a 364-day revolving line of credit (the "Facility") with a group of commercial banks allowing borrowing of up to $60.0 million, and maturing on September 25, 2015. The interest rate applied on the Facility will be at the Company's election either 30-day or 90-day LIBOR plus 1.95% or Prime minus 0.50% at the time the advance is made. Any amounts outstanding under the Facility upon or before maturity may be converted, at the Company's option, to an amortizing term loan, with the balance of such loan due September 26, 2017. At March 31, 2015, no amounts have been drawn on the Facility.
	Secured Borrowings - Also included in short-term and secured borrowings on the Consolidated Statements of Financial Condition are amounts related to certain loan participation agreements on loans we originated that were classified as secured borrowings because they did not qualify for sale accounting treatment. As of March 31, 2015 and December 31, 2014, these loan participation agreements totaled $5.8 million and $4.4 million, respectively. A corresponding amount was recorded within loans on the Consolidated Statements of Financial Condition at each of these dates.

LONGTERM_DEBT_LongTerm_Debt

LONG-TERM DEBT Long-Term Debt	3 Months Ended
	Mar. 31, 2015
Long-term Debt, Unclassified [Abstract]
Long-term Debt [Text Block]	LONG-TERM DEBT
	Long-Term Debt
	(Dollars in thousands)
					March 31,		December 31,
					2015		2014
	Parent Company:
	2.92% junior subordinated debentures due 2034		(1)(a)		$	8,248	$	8,248
	1.98% junior subordinated debentures due 2035		(2)(a)		51,547		51,547
	1.77% junior subordinated debentures due 2035		(3)(a)		41,238		41,238
	10.00% junior subordinated debentures due 2068			(a)	68,755		68,755
	7.125% subordinated debentures due 2042	(b)			125,000		125,000
	Subtotal				294,788		294,788
	Subsidiaries:
	FHLB advances				50,000		50,000
	Total long-term debt				$	344,788	$	344,788
	(1)	Variable rate in effect at March 31, 2015 based on three-month LIBOR +2.65%.
	(2)	Variable rate in effect at March 31, 2015, based on three-month LIBOR +1.71%.
	(3)	Variable rate in effect at March 31, 2015, based on three-month LIBOR +1.50%.
	(a)	Under the final regulatory capital rules issued in July 2013, these instruments are grandfathered for inclusion as a component of Tier 1 capital, although the Tier 1 capital treatment for these instruments will be subject to phase-out due to certain acquisitions.
	(b)	Qualifies as Tier 2 capital for regulatory capital purposes.
	The $169.8 million in junior subordinated debentures presented in the table above were issued to four separate wholly-owned trusts for the purpose of issuing Company-obligated mandatorily redeemable trust preferred securities. Refer to Note 9 for further information on the nature and terms of these and previously issued debentures.
	At March 31, 2015, outstanding long-term FHLB advances were secured by qualifying residential, multi-family, commercial real estate, and home equity lines of credit. From time to time we may pledge eligible real estate backed securities to support additional borrowings.
	Maturity and Rate Schedule for FHLB Long-Term Advances
	(Dollars in thousands)
		31-Mar-15
		Amount			Rate
	Maturity Date:
	March 25, 2019	$	2,000		4.26	%
	May 22, 2019	3,000			4.68	%
	September 12, 2019 (1)	15,000			3.72	%
	September 26, 2019 (1)	15,000			3.69	%
	December 9, 2019 (2)	15,000			3.58	%
	Total	$	50,000		3.75	%
	(1)	Provides for a one-time option to increase the advances in September 2016, up to $150.0 million each at the same fixed rate as the original advance. The advances include prepayment features and are subject to a prepayment fee.
	(2)	Provides for a one-time option to increase the advances in December 2016, up to $150.0 million each at the same fixed rate as the original advance. The advances include prepayment features and are subject to a prepayment fee.
	We reclassify long-term debt to short-term borrowings when the remaining maturity becomes less than one year.
	Scheduled Maturities of Long-Term Debt
	(Amounts in thousands)
		Total
	Year ending December 31,
	2019	$	50,000
	2020 and thereafter	294,788
	Total	$	344,788

JUNIOR_SUBORDINATED_DEFERRABLE

JUNIOR SUBORDINATED DEFERRABLE INTEREST DEBENTURES HELD BY TRUSTS THAT ISSUED GUARANTEED CAPITAL DEBT SECURITIES	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
JUNIOR SUBORDINATED DEFERRABLE INTEREST DEBENTURES HELD BY TRUSTS THAT ISSUED GUARANTEED CAPITAL DEBT SECURITIES	JUNIOR SUBORDINATED DEFERRABLE INTEREST DEBENTURES HELD BY TRUSTS THAT ISSUED GUARANTEED CAPITAL DEBT SECURITIES
	As of March 31, 2015, we sponsored and wholly owned 100% of the common equity of four trusts that were formed for the purpose of issuing Company obligated mandatorily redeemable trust preferred securities ("Trust Preferred Securities") to third-party investors and investing the proceeds from the sale of the Trust Preferred Securities solely in a series of junior subordinated debentures of the Company ("Debentures"). The Debentures held by the trusts, which in aggregate totaled $169.8 million at March 31, 2015, are the sole assets of each respective trust. Our obligations under the Debentures and related documents, including the indentures, the declarations of trust and related Company guarantees, taken together, constitute a full and unconditional guarantee by the Company on a subordinated basis of distributions and redemption payments and liquidation payments on the Trust Preferred Securities. We currently have the right to redeem, in whole or in part, subject to any required regulatory approval, all or any series of the Debentures, in each case, at a redemption price of 100% of the principal amount of the Debentures being redeemed plus any accrued but unpaid interest to the redemption date. The repayment, redemption or repurchase of any of the Debentures would be subject to the terms of the applicable indenture and would result in a corresponding repayment, redemption or repurchase of an equivalent amount of the related series of Trust Preferred Securities. Any redemption of the 10% Debentures held by the PrivateBancorp Capital Trust IV ("Capital Trust IV") would be subject to the terms of the replacement capital covenant described below and any required regulatory approval.
	In connection with the issuance in 2008 of the 10% Debentures, which rank junior to the other Debentures, we entered into a replacement capital covenant that relates to redemption of the 10% Debentures and the related Trust Preferred Securities. Under the replacement capital covenant, as amended in October 2012, we committed, for the benefit of certain debt holders, that we would not repay, redeem or repurchase the 10% Debentures or the related Trust Preferred Securities prior to June 2048 unless we have (1) obtained any required regulatory approval, and (2) raised certain amounts of qualifying equity or equity-like replacement capital at any time after October 10, 2012. The replacement capital covenant benefits holders of our "covered debt" as specified under the terms of the replacement capital covenant. Currently, under the replacement capital covenant, the "covered debt" is the Debentures held by PrivateBancorp Statutory Trust II. In the event that the Company's 7.125% subordinated debentures due 2042 are designated as or become the covered debt under the replacement capital covenant, the terms of such debentures provide that the Company is authorized to terminate the replacement capital covenant without any further action or payment. We may amend or terminate the replacement capital covenant in certain circumstances without the consent of the holders of the covered debt.
	Under current accounting rules, the trusts qualify as variable interest entities for which we are not the primary beneficiary and therefore are ineligible for consolidation in our financial statements. The Debentures issued by us to the trusts are included in our Consolidated Statements of Financial Condition as "long-term debt" with the corresponding interest distributions recorded as interest expense. The common shares issued by the trusts are included in other assets in our Consolidated Statements of Financial Condition with the related dividend distributions recorded in other non-interest income.
	Common Securities, Preferred Securities, and Related Debentures
	(Dollars in thousands)
			Common Securities Issued		Trust Preferred Securities				Earliest Redemption Date (on or after) (3)		Principal Amount of
					Issued (1)						Debentures (3)
		Issuance					Coupon			Maturity	March 31,		December 31,
		Date					Rate (2)				2015		2014
	Bloomfield Hills Statutory Trust I	May 2004	$	248	$	8,000	2.92	%	June 17, 2009	Jun-34	$	8,248	$	8,248
	PrivateBancorp Statutory Trust II	Jun. 2005	1,547		50,000		1.98	%	Sep 15, 2010	Sept. 2035	51,547		51,547
	PrivateBancorp Statutory Trust III	Dec. 2005	1,238		40,000		1.77	%	Dec 15, 2010	Dec. 2035	41,238		41,238
	PrivateBancorp Capital Trust IV	May 2008	5		68,750		10	%	June 15, 2013	Jun-68	68,755		68,755
	Total		$	3,038	$	166,750					$	169,788	$	169,788
	(1)	The trust preferred securities accrue distributions at a rate equal to the interest rate on and have a maturity identical to that of the related Debentures. The trust preferred securities will be redeemed upon maturity or earlier redemption of the related Debentures.
	(2)	Reflects the coupon rate in effect at March 31, 2015. The coupon rate for the Bloomfield Hills Statutory Trust I is a variable rate and is based on three-month LIBOR plus 2.65%. The coupon rates for the PrivateBancorp Statutory Trusts II and III are at a variable rate based on three-month LIBOR plus 1.71% for Trust II and three-month LIBOR plus 1.50% for Trust III. The coupon rate for the PrivateBancorp Capital Trust IV is fixed. Distributions for all of the Trusts are payable quarterly. We have the right to defer payment of interest on the Debentures at any time or from time to time for a period not exceeding ten years in the case of the Debentures held by Trust IV, and five years in the case of all other Debentures, without causing an event of default under the related indenture, provided no extension period may extend beyond the stated maturity of the Debentures. During such extension period, distributions on the trust preferred securities would also be deferred, and our ability to pay dividends on our common stock would generally be prohibited. The Federal Reserve has the ability to prevent interest payments on the Debentures.
	(3)	The trust preferred securities are subject to mandatory redemption, in whole or in part, upon repayment of the Debentures at maturity or upon their earlier redemption in whole or in part. The Debentures are redeemable in whole or in part prior to maturity at any time after the dates shown in the table and only after we have obtained Federal Reserve approval, if then required under applicable guidelines or regulations.

EQUITY

EQUITY	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
EQUITY	EQUITY
	Preferred Stock
	At March 31, 2015 and December 31, 2014, there were 1 million shares of preferred stock authorized and none issued or outstanding.
	Nonvoting Common Stock
	At March 31, 2015 and December 31, 2014, there were 5 million shares of nonvoting common stock authorized and none issued or outstanding.
	Treasury Stock
	The Company reissues treasury stock, when available, or new shares to fulfill its obligation to issue shares granted pursuant to the share-based compensation plans. Treasury shares are reissued at average cost. The Company held 160,193 shares and 1,704 shares in treasury at March 31, 2015 and December 31, 2014, respectively.
	Comprehensive Income
	Change in Accumulated Other Comprehensive Income ("AOCI") by Component
	(Amounts in thousands)
		Quarter Ended March 31,
		2015									2014
		Unrealized Gain on Available-for-Sale Securities			Accumulated			Total			Unrealized Gain on Available-for-Sale Securities			Accumulated			Total
					(Loss) Gain on Effective									(Loss) Gain on Effective
					Cash Flow									Cash Flow
					Hedges									Hedges
	Balance at beginning of period	$	19,448		$	1,469		$	20,917		$	12,960		$	(3,116	)	$	9,844
	Increase in unrealized gains on securities	8,590			—			8,590			3,677			—			3,677
	Increase in unrealized gains on cash flow hedges	—			8,630			8,630			—			4,137			4,137
	Tax expense on increase in unrealized gains	(3,358		)	(3,369		)	(6,727		)	(1,451		)	(1,623		)	(3,074		)
	Other comprehensive income before reclassifications	5,232			5,261			10,493			2,226			2,514			4,740
	Reclassification adjustment of net gains included in net income (1)	(534		)	(2,538		)	(3,072		)	(331		)	(2,043		)	(2,374		)
	Reclassification adjustment for tax expense on realized net gains (2)	210			999			1,209			131			806			937
	Amounts reclassified from AOCI	(324		)	(1,539		)	(1,863		)	(200		)	(1,237		)	(1,437		)
	Net current period other comprehensive income	4,908			3,722			8,630			2,026			1,277			3,303
	Balance at end of period	$	24,356		$	5,191		$	29,547		$	14,986		$	(1,839	)	$	13,147
	(1)	The amounts reclassified from AOCI for the available-for-sale securities are included in net securities gains on the Consolidated Statements of Income, while the amounts reclassified from AOCI for cash flow hedges are included in interest income on loans on the Consolidated Statements of Income.
	(2)	The tax expense amounts reclassified from AOCI in connection with the available-for-sale securities reclassification and cash flow hedges reclassification are included in income tax provision on the Consolidated Statements of Income.

EARNINGS_PER_COMMON_SHARE

EARNINGS PER COMMON SHARE	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
EARNINGS PER COMMON SHARE	EARNINGS PER COMMON SHARE
	Basic and Diluted Earnings per Common Share
	(Amounts in thousands, except per share data)
		Quarter Ended March 31,
		2015			2014
	Basic earnings per common share
	Net income	$	41,484		$	34,505
	Net income allocated to participating stockholders (1)	(463		)	(613		)
	Net income allocated to common stockholders	$	41,021		$	33,892
	Weighted-average common shares outstanding	77,407			76,675
	Basic earnings per common share	$	0.53		$	0.44
	Diluted earnings per common share
	Diluted earnings applicable to common stockholders (2)	$	41,028		$	33,897
	Weighted-average diluted common shares outstanding:
	Weighted-average common shares outstanding	77,407			76,675
	Dilutive effect of stock awards (3)	1,105			742
	Weighted-average diluted common shares outstanding	78,512			77,417
	Diluted earnings per common share	$	0.52		$	0.44
	(1)	Participating stockholders are those that hold certain share-based payment awards that contain nonforfeitable rights to dividends or dividend equivalents. Such shares or units are considered participating securities (i.e., certain of the Company’s deferred and restricted stock units and nonvested restricted stock awards).
	(2)	Net income allocated to common stockholders for basic and diluted earnings per share may differ under the two-class method as a result of adding common stock equivalents for options to dilutive shares outstanding, which alters the ratio used to allocate earnings to common stockholders and participating securities for the purposes of calculating diluted earnings per share.
	(3)	For the quarters ended March 31, 2015 and 2014, the weighted-average outstanding non-participating securities of 730,000 and 1.2 million shares, respectively, were not included in the computation of diluted earnings per common share because their inclusion would have been antidilutive for the periods presented.

INCOME_TAXES

INCOME TAXES	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
INCOME TAXES	INCOME TAXES
	Income Tax Provision Analysis
	(Dollars in thousands)
		Quarter Ended
		March 31,
		2015			2014
	Income before income taxes	$	66,718		$	55,531
	Income tax provision:
	Current income tax provision	$	21,540		$	19,867
	Deferred income tax provision	3,694			1,159
	Total income tax provision	$	25,234		$	21,026
	Effective tax rate	37.8		%	37.9		%
	Deferred Tax Assets
	Net deferred tax assets totaled $88.9 million at March 31, 2015 and $98.2 million at December 31, 2014. Net deferred tax assets are included in other assets in the accompanying Consolidated Statements of Financial Condition.
	At March 31, 2015, we have concluded that it is more likely than not that the deferred tax assets will be realized and no valuation allowance was recorded. This conclusion was based in part on our recent earnings history, on both a book and tax basis, and our outlook for earnings and taxable income in future periods.
	At both March 31, 2015 and December 31, 2014, we had $212,000, respectively, of unrecognized tax benefits relating to uncertain tax positions that, if recognized, would impact the effective tax rate.

DERIVATIVE_INSTRUMENTS

DERIVATIVE INSTRUMENTS	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
DERIVATIVE INSTRUMENTS	DERIVATIVE INSTRUMENTS
	We utilize an overall risk management strategy that incorporates the use of derivative instruments to reduce both interest rate risk (relating to mortgage loan commitments and planned sales of loans) and foreign currency volatility (relating to certain loans denominated in currencies other than the U.S. dollar). We also use these instruments to accommodate our clients as we provide them with risk management solutions. None of the client-related and other end-user derivatives, noted in the table below, were designated as hedging instruments for accounting purposes at March 31, 2015 and December 31, 2014.
	We also use interest rate derivatives to hedge variability in forecasted interest cash flows in our loan portfolio which is comprised primarily of floating-rate loans. These derivatives are designated as cash flow hedges.
	Derivatives expose us to counterparty credit risk. Credit risk is managed through our standard underwriting process. Actual exposures are monitored against various types of credit limits established to contain risk within parameters. Additionally, credit risk is managed through the use of collateral, netting agreements, and the establishment of internal concentration limits by financial institution.
	Notional Amounts and Fair Value of Derivative Instruments
	(Amounts in thousands)
		Asset Derivatives												Liability Derivatives
		31-Mar-15						31-Dec-14						31-Mar-15					31-Dec-14
		Notional (1)			Fair			Notional (1)			Fair			Notional (1)		Fair			Notional (1)		Fair
					Value						Value					Value					Value
	Derivatives designated as hedging instruments:
	Interest rate contracts	$	725,000		$	8,491		$	550,000		$	4,542		$	75,000	$	441		$	250,000	$	2,715
	Derivatives not designated as hedging instruments:
	Client-related derivatives:
	Interest rate contracts	$	3,982,438		$	54,821		$	3,881,202		$	42,879		$	3,982,438	$	56,520		$	3,743,827	$	43,792
	Foreign exchange contracts	173,672			9,056			98,285			5,183			149,430		8,433			86,582		4,659
	Credit contracts (1)	94,241			20			98,478			19			110,426		26			100,941		24
	Total client-related derivatives				$	63,897					$	48,081				$	64,979				$	48,475
	Other end-user derivatives:
	Foreign exchange contracts	$	10,937		$	115		$	18,551		$	241		$	4,566	$	18		$	2,892	$	45
	Mortgage banking derivatives				479						786					534					801
	Total other end-user derivatives				$	594					$	1,027				$	552				$	846
	Total derivatives not designated as hedging instruments				$	64,491					$	49,108				$	65,531				$	49,321
	Netting adjustments (2)				(16,375		)				(10,588		)			(39,005		)			(25,269		)
	Total derivatives				$	56,607					$	43,062				$	26,967				$	26,767
	(1)	The remaining average notional amounts are shown for credit contracts.
	(2)	Represents netting of derivative asset and liability balances, and related cash collateral, with the same counterparty subject to master netting agreements.
	Master Netting Agreements
	Certain of our derivative contracts are subject to enforceable master netting agreements with derivative counterparties. Authoritative accounting guidance permits the netting of derivative assets and liabilities when a legally enforceable master netting agreement exists between us and a derivative counterparty. A master netting agreement is an agreement between two counterparties who have multiple derivative contracts with each other that provide for the net settlement of contracts through a single payment, in a single currency, in the event of default on or termination of any one contract. For those derivative contracts subject to enforceable master netting agreements, derivative assets and liabilities, and related cash collateral, with the same counterparty are reported on a net basis within derivative assets and derivative liabilities on the Consolidated Statements of Financial Condition.
	Derivative contracts may require us to provide or receive cash or financial instrument collateral. Collateral associated with derivative assets and liabilities subject to enforceable master netting agreements with the same counterparty is posted on a net basis. We have pledged cash or financial collateral in accordance with each counterparty's collateral posting requirements for all of the Company's derivative assets and liabilities in a net liability position as of March 31, 2015. Certain collateral posting requirements are subject to posting thresholds and minimum transfer amounts, such that we are only required to post collateral once the posting threshold is met, and any adjustments to the amount of collateral posted must meet minimum transfer amounts.
	As of March 31, 2015, $22.7 million of cash collateral pledged was netted with the related derivative liabilities and $57,000 of the $90,000 cash collateral received was netted with the related derivative assets on the Consolidated Statement of Financial Condition. To the extent not netted against derivative fair values under a master netting agreement, the excess collateral received or pledged is included in other short-term borrowings or other investments, respectively. There was no excess cash collateral pledged at March 31, 2015. Any securities pledged to counterparties as financial instrument collateral remain on the Consolidated Statements of Financial Condition as long as we do not default.
	The following table presents information about our derivative assets and liabilities and the related collateral by derivative type (e.g., interest rate contracts). As we post collateral with counterparties on the basis of our net position in all derivative contracts with a given counterparty, the information presented below aggregates the derivative contracts entered into with the same counterparty.
	Offsetting of Derivative Assets and Liabilities
	(Amounts in thousands)
		Gross Amounts of Recognized Assets / Liabilities (1)			Gross Amounts Offset (2)			Net Amount Presented on the Statement of Financial Condition			Gross Amounts Not Offset on the Statement of Financial Condition (3)					Net Amount
											Financial Instruments (4)			Cash Collateral
	As of March 31, 2015
	Derivative assets:
	Interest rate contracts	$	63,312		$	(10,462	)	$	52,850		$	(721	)	$	—	$	52,129
	Foreign exchange contracts	6,508			(5,912		)	596			—			—		596
	Credit contracts	20			(1		)	19			—			—		19
	Total derivatives subject to a master netting agreement	69,840			(16,375		)	53,465			(721		)	—		52,744
	Total derivatives not subject to a master netting agreement	3,142			—			3,142			—			—		3,142
	Total derivatives	$	72,982		$	(16,375	)	$	56,607		$	(721	)	$	—	$	55,886
	Derivative liabilities:
	Interest rate contracts	$	56,961		$	(36,426	)	$	20,535		$	(15,482	)	$	—	$	5,053
	Foreign exchange contracts	5,041			(2,570		)	2,471			(1,863		)	—		608
	Credit contracts	26			(9		)	17			(13		)	—		4
	Total derivatives subject to a master netting agreement	62,028			(39,005		)	23,023			(17,358		)	—		5,665
	Total derivatives not subject to a master netting agreement	3,944			—			3,944			—			—		3,944
	Total derivatives	$	65,972		$	(39,005	)	$	26,967		$	(17,358	)	$	—	$	9,609
	(1)	All derivative contracts are over-the-counter contracts.
	(2)	Represents end-user, client-related and cash flow hedging derivative contracts and related cash collateral entered into with the same counterparty and subject to a master netting agreement.
	(3)	Collateralization is determined at the counterparty level. If overcollateralization exists, the amount shown is limited to the fair value of the derivative.
	(4)	Financial instruments are disclosed at fair value. Financial instrument collateral is allocated pro-rata amongst the derivative liabilities to which it relates.
	Offsetting of Derivative Assets and Liabilities (Continued)
	(Amounts in thousands)
		Gross Amounts of Recognized Assets / Liabilities (1)			Gross Amounts Offset (2)			Net Amount Presented on the Statement of Financial Condition			Gross Amounts Not Offset on the Statement of Financial Condition (3)					Net Amount
											Financial Instruments (4)			Cash Collateral
	As of December 31, 2014
	Derivative assets:
	Interest rate contracts	$	47,421		$	(7,433	)	$	39,988		$	—		$	—	$	39,988
	Foreign exchange contracts	3,664			(3,154		)	510			—			—		510
	Credit contracts	19			(1		)	18			—			—		18
Total derivatives subject to a master netting agreement	51,104			(10,588		)	40,516			—			—		40,516
Total derivatives not subject to a master netting agreement	2,546			—			2,546			—			—		2,546
Total derivatives	$	53,650		$	(10,588	)	$	43,062		$	—		$	—	$	43,062
Derivative liabilities:
Interest rate contracts	$	46,507		$	(24,067	)	$	22,440		$	(17,755	)	$	—	$	4,685
Foreign exchange contracts	2,421			(1,202		)	1,219			(965		)	—		254
Credit contracts	24			—			24			(19		)	—		5
Total derivatives subject to a master netting agreement	48,952			(25,269		)	23,683			(18,739		)	—		4,944
Total derivatives not subject to a master netting agreement	3,084			—			3,084			—			—		3,084
Total derivatives	$	52,036		$	(25,269	)	$	26,767		$	(18,739	)	$	—	$	8,028
(1)	All derivative contracts are over-the-counter contracts.
(2)	Represents end-user, client-related and cash flow hedging derivative contracts entered into with the same counterparty and subject to a master netting agreement.
(3)	Collateralization is determined at the counterparty level. If overcollateralization exists, the amount shown is limited to the fair value of the derivative.
(4)	Financial instruments are disclosed at fair value. Financial instrument collateral is allocated pro-rata amongst the derivative liabilities to which it relates.
Certain of our derivative contracts contain embedded credit risk contingent features that if triggered either allow the derivative counterparty to terminate the derivative or require additional collateral. These contingent features are triggered if we do not meet specified financial performance indicators such as minimum capital ratios under the Federal banking agencies’ guidelines. All such requirements were met at March 31, 2015 and December 31, 2014. Details on these derivative contracts are set forth in the following table.
Derivatives Subject to Credit Risk Contingency Features
(Amounts in thousands)
	March 31,			December 31,
	2015			2014
Fair value of derivatives with credit contingency features in a net liability position	$	13,291		$	14,596
Collateral posted for those transactions in a net liability position	$	15,226		$	16,865
If credit risk contingency features were triggered:
Additional collateral required to be posted to derivative counterparties	$	—		$	—
Outstanding derivative instruments that would be immediately settled	$	13,291		$	14,596
Derivatives Designated in Hedge Relationships
The objective of our hedging program is to use interest rate derivatives to manage our exposure to interest rate movements.
Cash Flow Hedges – Under our cash flow hedging program we enter into receive fixed/pay variable interest rate swaps to convert certain floating-rate commercial loan cash flows to fixed-rate to reduce the variability in forecasted interest cash flows due to market interest rate changes. We use regression analysis to assess the effectiveness of cash flow hedges at both the inception of the hedge relationship and on an ongoing basis. Ineffectiveness is generally measured as the amount by which the cumulative change in fair value of the hedging instrument exceeds the present value of the cumulative change in the expected cash flows of the hedged item. Measured ineffectiveness is recognized directly in other non-interest income in the Consolidated Statements of Income. During the quarter ended March 31, 2015, there were no gains or losses from cash flow hedge derivatives related to ineffectiveness that were reclassified to current earnings. The effective portion of the gains or losses on cash flow hedges are recorded, net of tax, in accumulated other comprehensive income ("AOCI") and are subsequently reclassified to interest income on loans in the period that the hedged interest cash flows affect earnings. As of March 31, 2015, the maximum length of time over which forecasted interest cash flows are hedged is five years. There are no components of derivative gains or losses excluded from the assessment of hedge effectiveness related to our cash flow hedge strategy.
Change in Accumulated Other Comprehensive Income
Related to Interest Rate Swaps Designated as Cash Flow Hedge
(Amounts in thousands)
	Quarter Ended March 31,
	2015						2014
	Pre-tax			After-tax			Pre-tax			After-tax
Accumulated unrealized gain (loss) at beginning of period	$	2,405		$	1,469		$	(5,110	)	$	(3,116	)
Amount of gain recognized in AOCI (effective portion)	8,630			5,261			4,137			2,514
Amount reclassified from AOCI to interest income on loans	(2,538		)	(1,539		)	(2,043		)	(1,237		)
Accumulated unrealized gain (loss) at end of period	$	8,497		$	5,191		$	(3,016	)	$	(1,839	)
As of March 31, 2015, $5.2 million in net deferred gains, net of tax, recorded in AOCI are expected to be reclassified into earnings during the next twelve months. This amount could differ from amounts actually recognized due to changes in interest rates, hedge de-designations, and the addition of other hedges subsequent to March 31, 2015. During the quarter ended March 31, 2015, there were no gains or losses from cash flow hedge derivatives reclassified to current earnings because it became probable that the original forecasted transaction would not occur.
Derivatives Not Designated in Hedge Relationships
Other End-User Derivatives – We enter into derivatives that include commitments to fund residential mortgage loans to be sold into the secondary market and forward commitments for the future delivery of residential mortgage loans. It is our practice to enter into forward commitments for the future delivery of residential mortgage loans when we enter into customer interest rate lock commitments. This practice allows us to economically hedge the effect of changes in interest rates on our commitments to fund the loans as well as on our portfolio of mortgage loans held-for-sale. At March 31, 2015, the par value of our mortgage loans held-for-sale totaled $21.8 million, the notional value of our interest rate lock commitments totaled $83.2 million, and the notional value of our forward commitments for the future delivery of residential mortgage loans totaled $105.0 million.
We are also exposed at times to foreign exchange risk as a result of originating loans in which the principal and interest are settled in a currency other than U.S. dollars. As of March 31, 2015, our exposure was to the Euro, Canadian dollar, British pound and Danish Kroner on $14.7 million of loans. We manage this risk using forward currency derivatives.
Client-Related Derivatives – We offer, through our capital markets group, over-the-counter interest rate and foreign exchange derivatives to our clients, including but not limited to, interest rate swaps, interest rate options (also referred to as caps, floors, collars, etc.), foreign exchange forwards and options, as well as cash products such as foreign exchange spot transactions. When our clients enter into an interest rate or foreign exchange derivative transaction with us, we mitigate our exposure to market risk through the execution of off-setting positions with inter-bank dealer counterparties. Although the off-setting nature of transactions originated by our capital markets group limits our market risk exposure, they do expose us to other risks including counterparty credit, settlement, and operational risk.
To accommodate our loan clients, we occasionally enter into risk participation agreements ("RPA") with counterparty banks to either accept or transfer a portion of the credit risk related to their interest rate derivatives or transfer a portion of the credit risk related to our interest rate derivatives. This allows clients to execute an interest rate derivative with one bank while allowing for distribution of the credit risk among participating members. We have entered into written RPAs in which we accept a portion of the credit risk associated with an interest rate derivative of another bank's loan client in exchange for a fee. We manage this credit risk through our loan underwriting process, and when appropriate, the RPA is backed by collateral provided by the clients under their loan agreement.
The current payment/performance risk of written RPAs is assessed using internal risk ratings which range from 1 to 8 with the latter representing the highest credit risk. The risk rating is based on several factors including the financial condition of the RPA’s underlying derivative counterparty, present economic conditions, performance trends, leverage, and liquidity.
The maximum potential amount of future undiscounted payments that we could be required to make under our written RPAs assumes that the underlying derivative counterparty defaults and that the floating interest rate index of the underlying derivative remains at zero percent. In the event that we would have to pay out any amounts under our RPAs, we will seek to maximize the recovery of these amounts from assets that our clients pledged as collateral for the derivative and the related loan.
Risk Participation Agreements
(Dollars in thousands)
	March 31,			December 31,
	2015			2014
Fair value of written RPAs	$	26		$	24
Range of remaining terms to maturity (in years)	Less than 1 to 4			Less than 1 to 4
Range of assigned internal risk ratings	2 to 7			2 to 7
Maximum potential amount of future undiscounted payments	$	3,821		$	3,927
Percent of maximum potential amount of future undiscounted payments covered by proceeds from liquidation of pledged collateral	24		%	25		%
Gain (Loss) Recognized on Derivative Instruments
Not Designated in Hedging Relationship
(Amounts in thousands)
	Quarter Ended March 31,
	2015			2014
Gain on client-related derivatives recognized in capital markets products income:
Interest rate contracts	$	2,363		$	2,510
Foreign exchange contracts	1,753			1,415
Credit contracts	56			158
Total client-related derivatives	4,172			4,083
Gain (loss) on end-user derivatives recognized in other income:
Foreign exchange derivatives	1,050			6
Mortgage banking derivatives	(40		)	(182		)
Total end-user derivatives	1,010			(176		)
Total derivatives not designated in hedging relationship	$	5,182		$	3,907

COMMITMENTS_GUARANTEES_AND_CON

COMMITMENTS, GUARANTEES, AND CONTINGENT LIABILITIES	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
COMMITMENTS, GUARANTEES, AND CONTINGENT LIABILITIES	COMMITMENTS, GUARANTEES, AND CONTINGENT LIABILITIES
	Credit Extension Commitments and Guarantees
	In the normal course of business, we enter into a variety of financial instruments with off-balance sheet risk to meet the financing needs of our clients and to conduct lending activities. These instruments principally include commitments to extend credit, standby letters of credit, and commercial letters of credit. These instruments involve, to varying degrees, elements of credit and liquidity risk in excess of the amounts reflected in the Consolidated Statements of Financial Condition.
	Contractual or Notional Amounts of Financial Instruments (1)
	(Amounts in thousands)
		March 31,		December 31,
		2015		2014
	Commitments to extend credit:
	Home equity lines	$	133,911	$	129,943
	Residential 1-4 family construction	51,776		53,847
	Commercial real estate, other construction, and land development	1,205,048		1,123,123
	Commercial and industrial	4,101,972		4,031,217
	All other commitments	345,133		336,623
	Total commitments to extend credit	$	5,837,840	$	5,674,753
	Letters of credit:
	Financial standby	$	359,716	$	334,175
	Performance standby	37,667		38,167
	Commercial letters of credit	4,765		5,224
	Total letters of credit	$	402,148	$	377,566
	(1)	Includes covered loan commitments of $10.7 million and $11.0 million as of March 31, 2015 and December 31, 2014, respectively.
	Commitments to extend credit are agreements to lend funds to or issue letters of credit for the account of, a client as long as there is no violation of any condition established in the credit agreement. Commitments generally have fixed expiration dates or other termination clauses and variable interest rates tied to the prime rate or LIBOR and may require payment of a fee for the unused portion of the commitment or for the amounts issued but not drawn on letters of credit. All or a portion of unfunded commitments require regulatory capital support, except for unfunded commitments of less than one year that are unconditionally cancellable. Since many of our commitments are expected to expire without being drawn upon, the total commitment amounts do not necessarily represent future cash requirements of the borrowers. As of March 31, 2015, we had a reserve for unfunded commitments of $12.7 million, which reflects our estimate of inherent losses associated with these commitment obligations. The balance of this reserve changes based on a number of factors including: the balance of outstanding commitments and our assessment of the likelihood of borrowers to utilize these commitments. The reserve is recorded in other liabilities in the Consolidated Statements of Financial Condition.
	Standby and commercial letters of credit are conditional commitments issued by us to guarantee the performance of a client to a third party. Standby letters of credit include performance and financial guarantees for clients in connection with contracts between our clients and third parties. Standby letters of credit are agreements where we are obligated to make payment to a third party on behalf of a client in the event the client fails to meet their contractual obligations. Commercial letters of credit are issued specifically to facilitate commerce and typically result in the commitment being drawn on when the underlying transaction is consummated between the client and the third party. In most cases, the Company receives a fee for the amount of a letter of credit issued but not drawn upon.
	In the event of a client’s nonperformance, our credit loss exposure is equal to the contractual amount of those commitments. We manage this credit risk in a similar manner to evaluating credit risk in extending loans to clients under our credit policies. We use the same credit policies in making credit commitments as for on-balance sheet instruments, mitigating exposure to credit loss through various collateral requirements, if deemed necessary. In the event of nonperformance by the clients, we have rights to the underlying collateral, which could include commercial real estate, physical plant and property, inventory, receivables, cash and marketable securities.
	The maximum potential future payments guaranteed by us under standby letters of credit arrangements are equal to the contractual amount of the commitment. The unamortized fees associated with standby letters of credit, which are included in other liabilities in the Consolidated Statements of Financial Condition, totaled $2.6 million as of March 31, 2015. We amortize these amounts into income over the commitment period. As of March 31, 2015, standby letters of credit had a remaining weighted-average term of approximately 14 months, with remaining actual lives ranging from less than 1 year to 6 years.
	Other Commitments
	The Company has unfunded commitments to Community Reinvestment Act ("CRA") investments and other investment partnerships totaling $20.2 million at March 31, 2015. Of these commitments, $8.3 million related to legally-binding unfunded commitments for tax-credit investments and was included within other assets and other liabilities on the Consolidated Statements of Financial Condition.
	Credit Card Settlement Guarantees
	Our third-party corporate credit card provider issues corporate purchase credit cards on behalf of our commercial clients. The corporate purchase credit cards are issued to employees of certain of our commercial clients at the client’s direction and used for payment of business-related expenses. In most circumstances, these cards will be underwritten by our third-party provider. However, in certain circumstances, we may enter into a recourse agreement, which transfers the credit risk from the third-party provider to us in the event that the client fails to meet its financial payment obligation. In these circumstances, a total maximum exposure amount is established for our corporate client. In addition to the obligations presented in the prior table, the maximum potential future payments guaranteed by us under this third-party settlement guarantee were $13.5 million at March 31, 2015.
	We believe that the estimated amounts of maximum potential future payments are not representative of our actual potential loss given our insignificant historical losses from this third-party settlement guarantee program. As of March 31, 2015, we have no recorded contingent liability in the consolidated financial statements for this settlement guarantee program, and management believes that the probability of any loss under this arrangement is remote.
	Mortgage Loans Sold with Recourse
	Certain mortgage loans sold into the secondary market have limited recourse provisions. The losses for the three months ended March 31, 2015 and 2014 arising from limited recourse provisions were not material. Based on this experience, the Company has not established any liability for potential future losses relating to mortgage loans sold in prior periods.
	Legal Proceedings
	In June 2013, we were served with a complaint naming the Bank as an additional defendant in a lawsuit pending in the Circuit Court of the 21st Judicial Circuit, Kankakee County, Illinois known as Maas vs. Marek et. al. The lawsuit, brought by the beneficiaries of two trusts for which the Bank is serving as the successor trustee, seeks reimbursement of penalties and interest assessed by the IRS due to the late payment of certain generation skipping taxes by the trusts, as well as certain related attorney fees and other damages. The other named defendants include legal and accounting professionals that provided services related to the matters involved. In January 2014, the Circuit Court denied the Bank’s motion to dismiss, and the matter is now in the discovery process. Although we are not able to predict the likelihood of an adverse outcome, we currently anticipate that ultimate resolution of this matter will not have a material adverse impact on our financial condition or results of operations.
	As of March 31, 2015, there were various other legal proceedings pending against the Company and its subsidiaries in the ordinary course of business. Management does not believe that the outcome of these proceedings will have, individually or in the aggregate, a material adverse effect on the Company’s results of operations, financial condition or cash flows.

ESTIMATED_FAIR_VALUE_OF_FINANC

ESTIMATED FAIR VALUE OF FINANCIAL INSTRUMENTS	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
ESTIMATED FAIR VALUE OF FINANCIAL INSTRUMENTS	ESTIMATED FAIR VALUE OF FINANCIAL INSTRUMENTS
	We measure, monitor, and disclose certain of our assets and liabilities on a fair value basis. Fair value is used on a recurring basis to account for securities available-for-sale, mortgage loans held-for-sale, derivative assets, derivative liabilities, and certain other assets and other liabilities. In addition, fair value is used on a nonrecurring basis to apply lower-of-cost-or-market accounting to foreclosed real estate and certain other loans held-for-sale, evaluate assets or liabilities for impairment, including collateral-dependent impaired loans, and for disclosure purposes. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Depending on the nature of the asset or liability, we use various valuation techniques and input assumptions when estimating fair value.
	U.S. GAAP requires us to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value and establishes a fair value hierarchy that prioritizes the inputs used to measure fair value into three broad levels based on the reliability of the input assumptions. The hierarchy gives the highest priority to level 1 measurements and the lowest priority to level 3 measurements. The three levels of the fair value hierarchy are defined as follows:
	•	Level 1 – Unadjusted quoted prices for identical assets or liabilities traded in active markets.
	•	Level 2 – Observable inputs other than level 1 prices, such as quoted prices for similar instruments; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the asset or liability.
	•	Level 3 – Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.
	The categorization of where an asset or liability falls within the hierarchy is based on the lowest level of input that is significant to the fair value measurement.
	Valuation Methodology
	We believe our valuation methods are appropriate and consistent with other market participants. However, the use of different methodologies or assumptions to determine the fair value of certain financial instruments could result in a different estimate of fair value. Additionally, the methods used may produce a fair value calculation that may not be indicative of net realizable value or reflective of future fair values.
	The following describes the valuation methodologies we use for assets and liabilities measured at fair value, including the general classification of the assets and liabilities pursuant to the valuation hierarchy.
	Securities Available-for-Sale – Securities available-for-sale include U.S. Treasury, U.S. Agency, collateralized mortgage obligations, residential mortgage-backed securities, state and municipal securities, and foreign sovereign debt. Substantially all available-for-sale securities are fixed-income instruments that are not quoted on an exchange, but may be traded in active markets. The fair value of these securities is based on quoted market prices obtained from external pricing services. The principal markets for our securities portfolio are the secondary institutional markets, with an exit price that is predominantly reflective of bid level pricing in those markets. U.S. Treasury securities have been classified in level 1 of the valuation hierarchy. All other remaining securities are classified in level 2 of the valuation hierarchy. On a quarterly basis, the Company uses a variety of methods to validate the overall reasonableness of the fair values obtained from external pricing services, including evaluating pricing service inputs and methodologies, using exception reports based on analytical criteria, comparing prices obtained to prices received from other pricing sources, and reviewing the reasonableness of prices based on the Company’s knowledge of market liquidity and other market-related conditions. While we may challenge valuation inputs used in determining prices obtained from external pricing services based on our validation procedures, we have not altered the fair values ultimately provided by the external pricing services during the periods presented.
	Mortgage Loans Held-for-Sale – Mortgage loans held-for-sale represent residential mortgage loan originations intended to be sold in the secondary market. We have elected the fair value option for residential mortgage loans originated with the intention of selling to a third party. The election of the fair value option aligns the accounting for these loans with the related mortgage banking derivatives used to economically hedge them. These mortgage loans are measured at fair value as of each reporting date, with changes in fair value recognized through mortgage banking non-interest income. The fair value of mortgage loans held-for-sale is determined based on prices obtained for loans with similar characteristics from third party sources. On a quarterly basis, the Company validates the overall reasonableness of the fair values obtained from third party sources by comparing prices obtained to prices received from various other pricing sources, and reviewing the reasonableness of prices based on Company knowledge of market liquidity and other market-related conditions. Mortgage loans held-for-sale are classified in level 2 of the valuation hierarchy.
	Collateral-Dependent Impaired Loans – We do not record loans held for investment at fair value on a recurring basis. However, periodically, we record nonrecurring adjustments to reduce the carrying value of certain impaired loans based on fair value measurement. This population of impaired loans includes those for which repayment of the loan is expected to be provided solely by the underlying collateral. We measure the fair value of collateral-dependent impaired loans based on the fair value of the collateral securing these loans less estimated selling costs. A majority of collateral-dependent impaired loans are secured by real estate with the fair value generally determined based upon appraisals performed by a certified or licensed appraiser using a combination of valuation techniques such as sales comparison, income capitalization and cost approach and include inputs such as absorption rates, capitalization rates and comparables. We also consider other factors or recent developments that could result in adjustments to the collateral value estimates indicated in the appraisals. When a collateral-dependent loan is secured by non-real estate collateral such as receivables, inventory, or equipment, the fair value is generally determined based upon appraisals, field exams, or receivable reports. The valuation techniques and inputs are reviewed internally by an asset-based specialist for reasonableness of estimated liquidation costs, collectability probabilities, and other market data. Accordingly, fair value estimates for collateral-dependent impaired loans are classified in level 3 of the valuation hierarchy. The carrying value of all impaired loans and the related specific reserves are disclosed in Note 4.
	At the time a collateral-dependent loan is initially determined to be impaired, we review the existing appraisal. If the most recent appraisal is greater than one-year old, a new appraisal of the underlying collateral is obtained. For collateral-dependent impaired loans that are secured by real estate, we generally obtain "as is" appraisal values in order to evaluate impairment. When a collateral-dependent loan is secured by non-real estate collateral such as receivables, inventory, or equipment, the fair value is generally determined based upon appraisals, field exams, or receivable reports. The valuation techniques and inputs are reviewed internally by workout and/or asset-based specialists for reasonableness of estimated liquidation costs, collectability probabilities, and other market data. Appraisals for real estate collateral-dependent impaired loans in excess of $500,000 are updated with new independent appraisals at least annually and are formally reviewed by our internal appraisal department. Additional diligence is performed at the six-month interval between annual appraisals. If during the course of the six-month review process there is evidence supporting a meaningful decline in the value of collateral, the appraised value is either adjusted downward or a new appraisal is required to support the value of the impaired loan. As part of our internal review process, we consider other factors or recent developments that could adjust the valuations indicated in the appraisals or internal reviews. The Company’s internal appraisal review process validates the reasonableness of appraisals in conjunction with analyzing sales and market data from an array of market sources.
	Covered Asset OREO and OREO – Covered asset OREO and OREO generated from our originated book of business are valued on a nonrecurring basis using third-party appraisals of each property and our judgment of other relevant market conditions and are classified in level 3 of the valuation hierarchy. As part of our internal review process, we consider other factors or recent developments that could adjust the valuations indicated in the appraisals or internal reviews. Updated appraisals on both OREO portfolios are typically obtained every twelve months and evaluated internally at least every six months. In addition, both property-specific and market-specific factors as well as collateral type factors are taken into consideration, which may result in obtaining more frequent appraisal updates or internal assessments. Appraisals are conducted by third-party independent appraisers under internal direction and engagement using a combination of valuation techniques such as sales comparison, income capitalization and cost approach and include inputs such as absorption rates, capitalization rate and comparables. Any appraisal with a value in excess of $250,000 is subject to a compliance review. Appraisals received with a value in excess of $1.0 million are subject to a technical review. Appraisals are either reviewed internally by our appraisal department or sent to an outside technical firm if appropriate. Both levels of review involve a scope appropriate for the complexity and risk associated with the OREO. To validate the reasonableness of the appraisals obtained, the Company compares the appraised value to the actual sales price of properties sold and analyzes the reasons why a property may be sold for less than its appraised value.
	Derivative Assets and Derivative Liabilities – Derivative instruments with positive fair values are reported as an asset and derivative instruments with negative fair value are reported as liabilities, in both cases after taking into account the effects of master netting agreements. For derivative counterparties with which we have a master netting agreement, we measure nonperformance risk on the basis of our net exposure to the counterparty. The fair value of derivative assets and liabilities is determined based on prices obtained from third party advisors using standardized industry models. Many factors affect derivative values, including the level of interest rates, the market’s perception of our nonperformance risk as reflected in our credit spread, and our assessment of counterparty nonperformance risk. The nonperformance risk assessment is based on our evaluation of credit risk, or if available, on observable external assessments of credit risk. Values of derivative assets and liabilities are primarily based on observable inputs and are classified in level 2 of the valuation hierarchy, with the exception of certain client-related derivatives and risk participation agreements, as discussed below. On a quarterly basis, the Company uses a variety of methods to validate the overall reasonableness of the fair values obtained from third party advisors, including evaluating inputs and methodologies used by the third party advisors, comparing prices obtained to prices received from other pricing sources, and reviewing the reasonableness of prices based on the Company's knowledge of market liquidity and other market-related conditions. While we may challenge valuation inputs used in determining prices obtained from third party advisors based on our validation procedures, during the quarters ended March 31, 2015 and 2014, we did not alter the fair values ultimately provided by the third party advisors.
	Level 3 derivatives include risk participation agreements and derivatives associated with clients whose loans are risk rated 6 or higher ("watch list derivative"). Refer to "Credit Quality Indicators" in Note 4 for further discussion on risk ratings. For these level 3 derivatives, the Company obtains prices from third party advisors, consistent with the valuation processes employed for the Company’s derivatives classified in level 2 of the fair value hierarchy, and then applies loss factors to adjust the prices obtained from third party advisors. The significant unobservable inputs that are employed in the valuation process for the risk participation agreements and watch list derivatives that cause these derivatives to be classified in level 3 of the fair value hierarchy are the historic loss factors specific to the particular industry segment and risk rating category. The loss factors are updated quarterly and are derived and aligned with the loss factors utilized in the calculation of the Company’s general reserve component of the allowance for loan losses. Changes in the fair value measurement of risk participation agreements and watch list derivatives are largely due to changes in the fair value of the derivative, risk rating adjustments and fluctuations in the pertinent historic average loss rate.
	Assets and Liabilities Measured at Fair Value on a Recurring Basis
	The following table presents the hierarchy level and fair value for each major category of assets and liabilities measured at fair value at March 31, 2015 and December 31, 2014 on a recurring basis.
	Fair Value Measurements on a Recurring Basis
	(Amounts in thousands)
		31-Mar-15															31-Dec-14
		Quoted				Significant				Significant				Total			Quoted		Significant			Significant			Total
		Prices in				Other				Unobservable							Prices in		Other			Unobservable
		Active				Observable				Inputs							Active		Observable			Inputs
		Markets for				Inputs				(Level 3)							Markets for		Inputs			(Level 3)
		Identical				(Level 2)											Identical		(Level 2)
		Assets															Assets
		(Level 1)															(Level 1)
	Assets:
	Securities available-for sale:
	U.S. Treasury	$	244,556			$	—			$	—			$	244,556		$	268,265	$	—		$	—		$	268,265
	U.S. Agency	—				46,806				—				46,806			—		46,258			—			46,258
	Collateralized mortgage obligations	—				127,828				—				127,828			—		136,933			—			136,933
	Residential mortgage-backed securities	—				829,413				—				829,413			—		846,078			—			846,078
	State and municipal securities	—				382,134				—				382,134			—		347,310			—			347,310
	Foreign sovereign debt	—				500				—				500			—		500			—			500
	Total securities available-for-sale	244,556				1,386,681				—				1,631,237			268,265		1,377,079			—			1,645,344
	Mortgage loans held-for-sale	—				21,866				—				21,866			—		42,215			—			42,215
	Derivative assets:
	Interest rate contract derivatives designated as hedging instruments	—				8,491				—				8,491			—		4,542			—			4,542
	Client-related derivatives	—				62,143				1,754				63,897			—		46,669			1,412			48,081
	Other end-user derivatives	—				594				—				594			—		1,027			—			1,027
	Netting adjustments	—				(15,686		)		(689		)		(16,375		)	—		(9,952		)	(636		)	(10,588		)
	Total derivative assets	—				55,542				1,065				56,607			—		42,286			776			43,062
	Total assets	$	244,556			$	1,464,089			$	1,065			$	1,709,710		$	268,265	$	1,461,580		$	776		$	1,730,621
	Liabilities:
	Derivative liabilities:
	Interest rate contract derivatives designated as hedging instruments	$	—			$	441			$	—			$	441		$	—	$	2,715		$	—		$	2,715
	Client-related derivatives	—				64,273				706				64,979			—		47,799			676			48,475
	Other end-user derivatives	—				552				—				552			—		846			—			846
	Netting adjustments	—				(38,316		)		(689		)		(39,005		)	—		(24,633		)	(636		)	(25,269		)
	Total derivative liabilities	$	—			$	26,950			$	17			$	26,967		$	—	$	26,727		$	40		$	26,767
	If a change in valuation techniques or input assumptions for an asset or liability occurred between periods, we would consider whether this would result in a transfer between the three levels of the fair value hierarchy. There have been no transfers of assets or liabilities between level 1 and level 2 of the valuation hierarchy between December 31, 2014 and March 31, 2015.
	There have been no other changes in the valuation techniques we used for assets and liabilities measured at fair value on a recurring basis from December 31, 2014 to March 31, 2015.
	Reconciliation of Beginning and Ending Fair Value for Those
	Fair Value Measurements Using Significant Unobservable Inputs (Level 3) (1)
	(Amounts in thousands)
		Quarter Ended March 31,
		2015								2014
		Derivative				Derivative				Derivative				Derivative
		Assets				(Liabilities)				Assets				(Liabilities)
	Balance at beginning of period	$	1,412			$	(676	)		$	448			$	(98	)
	Total gains:
Included in earnings (2)	312				(24		)		79				180
Purchases, issuances, sales and settlements:
Settlements	(500		)		147				(385		)		(245		)
Transfers into Level 3 (out of Level 2) (3)	884				(160		)		827				(446		)
Transfers out of Level 3 (into Level 2) (3)	(354		)		8				(112		)		—
Balance at end of period	$	1,754			$	(705	)		$	857			$	(609	)
Change in unrealized gains in earnings relating to assets and liabilities still held at end of period	$	241			$	24			$	7			$	166
(1)	Fair value is presented prior to giving effect to netting adjustments.
(2)	Amounts disclosed in this line are included in the Consolidated Statements of Income as capital markets products income for derivatives.
(3)	Transfers in and transfers out are recognized at the end of each quarterly reporting period. In general, derivative assets and liabilities are transferred into Level 3 from Level 2 due to a lack of observable market data, as there was deterioration in the credit risk of the derivative counterparty. Conversely, derivative assets and liabilities are transferred out of Level 3 into Level 2 due to an improvement in the credit risk of the derivative counterparty.
Financial Instruments Recorded Using the Fair Value Option
Difference Between Aggregate Fair Value and Aggregate Remaining Principal Balance
for Mortgage Loans Held-For-Sale Elected to be Carried at Fair Value
(Amounts in thousands)
	March 31,				December 31,
	2015				2014
Aggregate fair value	$	21,866			$	42,215
Difference (1)	(55		)		(16		)
Aggregate unpaid principal balance	$	21,811			$	42,199
(1)	The change in fair value is reflected in mortgage banking non-interest income.
As of March 31, 2015, none of the mortgage loans held-for-sale were on nonaccrual or 90 days or more past due and still accruing interest. Changes in fair value due to instrument-specific credit risk for the quarter ended March 31, 2015 were not material.
Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis
From time to time, we may be required to measure certain other financial assets at fair value on a nonrecurring basis. These adjustments to fair value usually result from the application of lower-of-cost-or-fair-value accounting or write-downs of individual assets when there is evidence of impairment.
The following table provides the fair value of those assets that were subject to fair value adjustments during the first quarter 2015 and 2014, and still held at March 31, 2015 and 2014, respectively. All fair value measurements on a nonrecurring basis were measured using level 3 of the valuation hierarchy.
Fair Value Measurements on a Nonrecurring Basis
(Amounts in thousands)
	Fair Value								Net (Gains) Losses
	March 31,								For the Quarter Ended March 31,
	2015				2014				2015				2014
Collateral-dependent impaired loans (1)	$	27,234			$	40,716			$	(1,653	)		$	5,612
OREO (2)	5,128				6,858				935				1,463
Total	$	32,362			$	47,574			$	(718	)		$	7,075
(1)	Represents the fair value of loans adjusted to the appraised value of the collateral with a write-down in fair value or change in specific reserves during the respective period. These fair value adjustments are recorded against the allowance for loan losses.
(2)	Represents the fair value of foreclosed properties that were adjusted subsequent to their initial classification as foreclosed assets. Write-downs are recognized as a component of net foreclosed real estate expense in the Consolidated Statements of Income.
There have been no changes in the valuation techniques we used for assets and liabilities measured at fair value on a nonrecurring basis from December 31, 2014 to March 31, 2015.
Additional Information Regarding Level 3 Fair Value Measurements
The following table presents information regarding the unobservable inputs developed by the Company for its level 3 fair value measurements.
Quantitative Information Regarding Level 3 Fair Value Measurements
(Dollars in thousands)
Financial Instrument:		Fair Value				Valuation Technique(s)		Unobservable		Range		Weighted
		of Assets /						Input				Average
		(Liabilities) at
		31-Mar-15
Watch list derivatives		$	1,054			Discounted cash flow		Loss factors		4.5% to 16.5%		13.9	%
Risk participation agreements		$	(6	)	(1)	Discounted cash flow		Loss factors		0.6% to 16.5%		4	%
Collateral-dependent impaired loans		$	27,234			Sales comparison,		Property specific		-2.0% to -15.9%		-8.1	%	(2)
						income capitalization		adjustment
						and/or cost approach
OREO		$	5,128			Sales comparison,		Property specific		-2.4% to -18.8%		-14.8	%	(2)
						income capitalization		adjustment
						and/or cost approach
(1)	Represents fair value of underlying swap.
(2)	Weighted average is calculated based on assets with a property specific adjustment.
The significant unobservable inputs used in the fair value measurement of the risk participation agreements and watch list derivatives are the historic loss factors. A significant increase (decrease) in the pertinent loss factor would result in a significantly lower (higher) fair value measurement.
Estimated Fair Value of Certain Financial Instruments
U.S. GAAP requires disclosure of the estimated fair values of certain financial instruments, both assets and liabilities, on and off-balance sheet, for which it is practical to estimate the fair value. Because the disclosure of estimated fair values provided herein excludes the fair value of certain other financial instruments and all non-financial instruments, any aggregation of the estimated fair value amounts presented would not represent total underlying value. Examples of non-financial instruments having value not disclosed herein include the future earnings potential of significant customer relationships and the value of our asset management operations and other fee-generating businesses. In addition, other significant assets including property, plant, and equipment and goodwill are not considered financial instruments and, therefore, have not been included in the disclosure.
Various methodologies and assumptions have been utilized in management’s determination of the estimated fair value of our financial instruments, which are detailed below. The fair value estimates are made at a discrete point in time based on relevant market information. Because no market exists for a significant portion of these financial instruments, fair value estimates are based on judgments regarding future expected economic conditions, loss experience, and risk characteristics of the financial instruments. These estimates are subjective, involve uncertainties, and cannot be determined with precision. Changes in assumptions could significantly affect the estimates.
In addition to the valuation methodology explained above for financial instruments recorded at fair value, the following methods and assumptions were used in estimating the fair value of financial instruments that are carried at cost in the Consolidated Statements of Financial Condition and includes the general classification of the assets and liabilities pursuant to the valuation hierarchy.
Short-term financial assets and liabilities – For financial instruments with a shorter-term or with no stated maturity, prevailing market rates, and limited credit risk, the carrying amounts approximate fair value. Those financial instruments include cash and due from banks, Federal funds sold and interest-bearing deposits in banks (including the receivable for cash collateral pledged), accrued interest receivable, and accrued interest payable. Accrued interest receivable and accrued interest payable are classified consistent with the hierarchy of their corresponding assets and liabilities.
Other loans held-for-sale - Included in loans held-for sale at March 31, 2015 and December 31, 2014 are $67.6 million and $36.6 million, respectively, of loans carried at the lower of aggregate cost or fair value. Also included in loans held-for-sale at December 31, 2014 are $36.3 million of loans held-for-sale in connection with the sale of the Company's banking office located in Norcross, Georgia, which closed in January 2015. Fair value estimates are based on the actual agreed upon price in the agreement.
Securities held-to-maturity – Securities held-to-maturity include collateralized mortgage obligations, residential mortgage-backed securities, agency commercial mortgage-backed securities and state and municipal securities. Substantially all held-to-maturity securities are fixed income instruments that are not quoted on an exchange, but may be traded in active markets. The fair value of these securities is based on quoted market prices obtained from external pricing services. The principal markets for our securities portfolio are the secondary institutional markets, with an exit price that is predominantly reflective of bid level pricing in those markets.
FHLB stock – The carrying value of FHLB stock approximates fair value as the stock is non-marketable, but can only be sold to the FHLB or another member institution at par.
Loans – The fair value of loans is calculated by discounting estimated cash flows through the estimated maturity using estimated market discount rates that reflect the credit and interest rate risk inherent in the loan. Cash flows are estimated by applying contractual payment terms to assumed interest rates. The estimate of maturity is based on contractual terms and includes assumptions that reflect our and the industry’s historical experience with repayments for each loan classification. The estimation is modified, as required, by the effect of current economic and lending conditions, collateral, and other factors.
Covered assets – Covered assets include acquired loans and foreclosed loan collateral covered under a loss sharing agreement with the FDIC (including the fair value of expected reimbursements from the FDIC). The fair value of covered assets is calculated by discounting contractual cash flows through the estimated maturity using estimated market discount rates that reflect the credit and interest rate risk inherent in the asset. The estimate of maturity is based on contractual terms and includes assumptions that reflect our and the industry’s historical experience with repayments for each asset classification. The estimate is modified, as required, by the effect of current economic and lending conditions, collateral, and other factors.
Investment in BOLI – The cash surrender value of our investment in bank owned life insurance approximates the fair value.
Deposit liabilities – The fair values disclosed for noninterest-bearing deposits, savings deposits, interest-bearing demand deposits, and money market deposits are approximately equal to the amount payable on demand at the reporting date (i.e., their carrying amounts). The fair values for certificate of deposits and time deposits were estimated using present value techniques by discounting the future cash flows at rates based on internal models and broker quotes.
Deposits held-for-sale – Deposits held-for-sale are recorded at the lower of cost or fair value. Amounts held at December 31, 2014 are deposits held-for-sale in connection with the sale of the Company's banking office located in Norcross, Georgia, which closed in January 2015. Fair value estimates are based upon the price and premium per the agreement.
Short-term and other borrowings – The fair value of FHLB advances with remaining maturities of one year or less is estimated by discounting the obligations using the rates currently offered for borrowings of similar remaining maturities. The fair value of secured borrowings is equal to the value of the loans they are collateralizing. See "Loans" above for further information. The carrying amount of the obligation for cash collateral held is considered to be its fair value because of its short-term nature.
Long-term debt – The fair value of the Company's fixed-rate long-term debt was estimated using the unadjusted publicly-available market price as of period end.
FHLB advances with remaining maturities greater than one year and the Company's variable-rate junior subordinated debentures are estimated by discounting future cash flows. For the FHLB advances with remaining maturities greater than one year, the Company discounts cash flows using quoted interest rates for similar financial instruments. For the Company's variable-rate junior subordinated debentures, we interpolate a discount rate we believe is appropriate based on quoted interest rates and entity specific adjustments.
Commitments – Given the limited interest rate risk posed by the commitments outstanding at period end due to their variable rate structure, termination clauses provided in the agreements, and the market rate of fees charged, we have deemed the fair value of commitments outstanding to be immaterial.
Financial Instruments
(Amounts in thousands)
	As of March 31, 2015
	Carrying Amount								Fair Value Measurements Using
					Fair Value				Level 1				Level 2			Level 3
Financial Assets:
Cash and due from banks	$	158,431			$	158,431			$	158,431			$	—		$	—
Federal funds sold and interest-bearing deposits in banks	799,953				799,953				—				799,953			—
Loans held-for-sale	89,461				89,461				—				89,461			—
Securities available-for-sale	1,631,237				1,631,237				244,556				1,386,681			—
Securities held-to-maturity	1,159,853				1,173,402				—				1,173,402			—
FHLB stock	28,556				28,556				—				28,556			—
Loans, net of allowance for loan losses and unearned fees	12,013,874				11,951,864				—				—			11,951,864
Covered assets, net of allowance for covered loan losses	26,170				32,030				—				—			32,030
Accrued interest receivable	41,202				41,202				—				—			41,202
Investment in BOLI	55,561				55,561				—				—			55,561
Derivative assets	56,607				56,607				—				55,542			1,065
Financial Liabilities:
Deposits	$	14,101,728			$	14,110,642			$	—			$	11,591,322		$	2,519,320
Short-term and secured borrowings	258,788				257,809				—				252,675			5,134
Long-term debt	344,788				338,520				206,537				54,942			77,041
Accrued interest payable	7,004				7,004				—				—			7,004
Derivative liabilities	26,967				26,967				—				26,950			17
Financial Instruments (Continued)
(Amounts in thousands)
	As of December 31, 2014
	Carrying Amount								Fair Value Measurements Using
					Fair Value				Level 1				Level 2			Level 3
Financial Assets:
Cash and due from banks	$	132,211			$	132,211			$	132,211			$	—		$	—
Federal funds sold and interest-bearing deposits in banks	292,341				292,341				—				292,341			—
Loans held-for-sale	115,161				115,161				—				115,161			—
Securities available-for-sale	1,645,344				1,645,344				268,265				1,377,079			—
Securities held-to-maturity	1,129,285				1,132,615				—				1,132,615			—
FHLB stock	28,666				28,666				—				28,666			—
Loans, net of allowance for loan losses and unearned fees	11,739,721				11,736,461				—				—			11,736,461
Covered assets, net of allowance for covered loan losses	28,941				33,988				—				—			33,988
Accrued interest receivable	40,531				40,531				—				—			40,531
Investment in BOLI	55,207				55,207				—				—			55,207
Derivative assets	43,062				43,062				—				42,286			776
Financial Liabilities:
Deposits	$	13,089,968			$	13,095,657			$	—			$	10,595,040		$	2,500,617
Deposits held-for-sale	122,216				117,572				—				117,572			—
Short-term and secured borrowings	432,385				430,944				—				427,150			3,794
Long-term debt	344,788				332,374				204,320				54,092			73,962
Accrued interest payable	6,948				6,948				—				—			6,948
Derivative liabilities	26,767				26,767				—				26,727			40

OPERATING_SEGMENTS

OPERATING SEGMENTS	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
OPERATING SEGMENTS	OPERATING SEGMENTS
	We have three primary operating segments: Banking, Asset Management and the Holding Company. With respect to the Banking and Asset Management segments, each is delineated by the products and services that each segment offers. The Banking operating segment is comprised of commercial and personal banking services, including mortgage originations. Commercial banking services are primarily provided to corporations and other business clients and include a wide array of lending and cash management products. Personal banking services offered to individuals, professionals, and entrepreneurs include direct lending and depository services. The Asset Management segment includes certain activities of our PrivateWealth group, including investment management, personal trust and estate administration, custodial and escrow, retirement plans and brokerage services. The activities of the third operating segment, the Holding Company, include the direct and indirect ownership of our banking subsidiary, the issuance of debt and intersegment eliminations.
	The accounting policies of the individual operating segments are the same as those of the Company as described in Note 1, "Summary of Significant Accounting Policies," to the Notes to Consolidated Financial Statements of our 2014 Annual Report on Form 10-K. Transactions between operating segments are primarily conducted at fair value, resulting in profits that are eliminated from consolidated results of operations.
	Financial results for each segment are presented below. For segment reporting purposes, the statement of financial condition of Asset Management is included with the Banking segment.
	Operating Segments Performance
	(Amounts in thousands)
		Quarter Ended March 31,
		Banking				Asset Management						Holding Company						Consolidated
												and Other
												Adjustments
		2015		2014		2015			2014			2015			2014			2015		2014
	Net interest income (loss)	$	126,498	$	115,152	$	899		$	787		$	(5,404	)	$	(7,187	)	$	121,993	$	108,752
	Provision for loan and covered loan losses	5,646		3,707		—			—			—			—			5,646		3,707
	Non-interest income	29,138		21,872		4,363			4,349			15			15			33,516		26,236
	Non-interest expense	75,935		68,660		4,312			4,076			2,898			3,014			83,145		75,750
	Income (loss) before taxes	74,055		64,657		950			1,060			(8,287		)	(10,186		)	66,718		55,531
	Income tax provision (benefit)	27,937		24,653		374			418			(3,077		)	(4,045		)	25,234		21,026
	Net income (loss)	$	46,118	$	40,004	$	576		$	642		$	(5,210	)	$	(6,141	)	$	41,484	$	34,505
		Banking				Holding Company and Other Adjustments(1)						Consolidated
	Selected Balances	3/31/15		12/31/14		3/31/15			12/31/14			3/31/15			12/31/14
	Assets	$	14,583,189	$	13,882,805	$	1,778,159		$	1,720,577		$	16,361,348		$	15,603,382
	Total loans	12,170,484		11,892,219		—			—			12,170,484			11,892,219
	Deposits, excluding deposits held-for-sale	14,156,257		13,150,600		(54,529		)	(60,632		)	14,101,728			13,089,968
	(1)	Deposit amounts represent the elimination of Holding Company cash accounts included in total deposits of the Banking segment.

VARIABLE_INTEREST_ENTITIES

VARIABLE INTEREST ENTITIES	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
VARIABLE INTEREST ENTITIES	VARIABLE INTEREST ENTITIES
	At March 31, 2015 and December 31, 2014, the Company had no variable interest entity ("VIE") consolidated in its financial statements. The table below presents our interests in VIEs that are not consolidated in our financial statements.
	Nonconsolidated VIEs
	(Amounts in thousands)
		31-Mar-15				31-Dec-14
		Carrying		Maximum		Carrying		Maximum
		Amount		Exposure		Amount		Exposure
				to Loss				to Loss
	Trust preferred capital securities issuances	$	169,788	$	—	$	169,788	$	—
	Community reinvestment investments	11,431		13,125		14,360		16,054
	Restructured loans to commercial clients (1):
	Outstanding loan balance	50,425		55,886		49,376		57,782
	Related derivative asset	2,961		2,961		6,533		6,533
	Total	$	234,605	$	71,972	$	240,057	$	80,369
	(1)	Excludes personal loans and loans to non-for-profit entities.
	Trust preferred capital securities issuances – As discussed in Note 9, we sponsor and wholly own 100% of the common equity of four trusts that were formed for the purpose of issuing trust preferred securities to third-party investors and investing the proceeds from the sale of the trust preferred securities solely in debentures issued by the Company. The trusts’ only assets are the principal balance of the Debentures and the related interest receivable, which are included within long-term debt in our Consolidated Statements of Financial Condition. The Company is not the primary beneficiary of the trusts and accordingly, the trusts are not consolidated in our financial statements.
	Community reinvestment investments – We hold certain investments in funds that make investments to further our community reinvestment initiatives. Such investments are included within other assets in our Consolidated Statements of Financial Condition. Certain of these investments meet the definition of a VIE, but the Company is not the primary beneficiary as we are a limited investor in those investment funds and do not have the power to direct their investment activities. Accordingly, we will continue to account for our interests in these investments on an unconsolidated basis. Our maximum exposure to loss is limited to the carrying amount plus additional required future capital contributions.
	A portion of our community reinvestment investments are investments in limited liability entities that invest in affordable housing projects that qualify for low-income housing tax credits. These investments entitle the Company to tax credits through 2031. Any new investments in qualified affordable housing projects entered into on or after January 1, 2014 that meet certain conditions will be accounted for using the proportional amortization method. Prior to January 1, 2014, the Company accounted for all of its investments in qualified affordable housing projects using the effective yield method and has elected to continue accounting for preexisting tax credit investments using the effective yield method as permitted under the accounting standards.
	The carrying value of the Company’s tax credit investments totaled $9.9 million and $10.0 million as of March 31, 2015 and December 31, 2014, respectively. The Company recognizes tax credits related to these investments, tax benefits from the operating losses generated by these investments, and amortization of the principal investment balances, all of which were immaterial during each of the three months ended March 31, 2015 and 2014. Commitments to provide future capital contributions totaling $8.3 million as of March 31, 2015, are expected to be paid through 2029. These investments are reviewed periodically for impairment. No impairment losses have been recorded for the three months ended March 31, 2015 and 2014.
	Restructured loans – For certain troubled commercial loans, we restructure the terms of the borrower’s debt in an effort to increase the probability of collecting amounts contractually due. Following a restructuring, the borrower entity typically meets the definition of a VIE, and economic events have proven that the entity’s equity is not sufficient to permit it to finance its activities without additional subordinated financial support or a restructuring of the terms of its financing. As we do not have the power to direct the activities that most significantly impact such troubled commercial borrowers’ operations, we are not considered the primary beneficiary even in situations where, based on the size of the financing provided, we are exposed to potentially significant benefits and losses of the borrowing entity. We have no contractual requirements to provide financial support to the borrowing entities beyond certain funding commitments established upon restructuring of the terms of the debt. Our interests in the troubled commercial borrowers include outstanding loans and related derivative assets. Our maximum exposure to loss is limited to these interests plus any additional future funding commitments.

SECURITIES_Tables

SECURITIES (Tables)	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Securities Portfolio	Securities Portfolio
	(Amounts in thousands)
		31-Mar-15												31-Dec-14
		Amortized Cost			Gross Unrealized						Fair Value			Amortized Cost		Gross Unrealized						Fair Value
					Gains			Losses								Gains			Losses
	Securities Available-for-Sale
	U.S. Treasury	$	243,608		$	1,186		$	(238	)	$	244,556		$	269,697	$	120		$	(1,552	)	$	268,265
	U.S. Agency	46,847			20			(61		)	46,806			46,959		—			(701		)	46,258
	Collateralized mortgage obligations	123,181			4,647			—			127,828			132,633		4,334			(34		)	136,933
	Residential mortgage-backed securities	802,921			27,797			(1,305		)	829,413			822,746		25,058			(1,726		)	846,078
	State and municipal securities	374,125			8,521			(512		)	382,134			340,810		7,222			(722		)	347,310
	Foreign sovereign debt	500			—			—			500			500		—			—			500
	Total	$	1,591,182		$	42,171		$	(2,116	)	$	1,631,237		$	1,613,345	$	36,734		$	(4,735	)	$	1,645,344
	Securities Held-to-Maturity
	Collateralized mortgage obligations	$	58,209		$	—		$	(1,273	)	$	56,936		$	59,960	$	—		$	(2,017	)	$	57,943
	Residential mortgage-backed securities	909,643			15,195			(1,470		)	923,368			885,235		9,410			(2,483		)	892,162
	Commercial mortgage-backed securities	190,932			1,710			(618		)	192,024			183,021		592			(2,176		)	181,437
	State and municipal securities	1,069			5			—			1,074			1,069		4			—			1,073
	Total	$	1,159,853		$	16,910		$	(3,361	)	$	1,173,402		$	1,129,285	$	10,006		$	(6,676	)	$	1,132,615
Securities in Unrealized Loss Position	Securities in Unrealized Loss Position
	(Amounts in thousands)
		Less Than 12 Months						12 Months or Longer						Total
		Fair			Unrealized			Fair			Unrealized			Fair		Unrealized
		Value			Losses			Value			Losses			Value		Losses
	As of March 31, 2015
	Securities Available-for-Sale
	U.S. Treasury	$	25,187		$	(46	)	$	52,348		$	(192	)	$	77,535	$	(238	)
	U.S. Agency	14,875			(61		)	—			—			14,875		(61		)
	Residential mortgage-backed securities	2,577			(6		)	86,266			(1,299		)	88,843		(1,305		)
	State and municipal securities	63,470			(441		)	4,623			(71		)	68,093		(512		)
	Total	$	106,109		$	(554	)	$	143,237		$	(1,562	)	$	249,346	$	(2,116	)
	Securities Held-to-Maturity
	Collateralized mortgage obligations	$	—		$	—		$	56,936		$	(1,273	)	$	56,936	$	(1,273	)
	Residential mortgage-backed securities	118,201			(643		)	64,950			(827		)	183,151		(1,470		)
	Commercial mortgage-backed securities	24,076			(124		)	50,056			(494		)	74,132		(618		)
	Total	$	142,277		$	(767	)	$	171,942		$	(2,594	)	$	314,219	$	(3,361	)
	As of December 31, 2014
	Securities Available-for-Sale
	U.S. Treasury	$	119,233		$	(159	)	$	123,117		$	(1,393	)	$	242,350	$	(1,552	)
	U.S. Agency	—			—			46,258			(701		)	46,258		(701		)
	Collateralized mortgage obligations	4,565			(34		)	—			—			4,565		(34		)
	Residential mortgage-backed securities	—			—			89,085			(1,726		)	89,085		(1,726		)
	State and municipal securities	53,092			(249		)	32,152			(473		)	85,244		(722		)
	Total	$	176,890		$	(442	)	$	290,612		$	(4,293	)	$	467,502	$	(4,735	)
	Securities Held-to-Maturity
	Collateralized mortgage obligations	$	—		$	—		$	57,943		$	(2,017	)	$	57,943	$	(2,017	)
	Residential mortgage-backed securities	45,867			(38		)	162,564			(2,445		)	208,431		(2,483		)
	Commercial mortgage-backed securities	10,021			(28		)	105,709			(2,148		)	115,730		(2,176		)
	Total	$	55,888		$	(66	)	$	326,216		$	(6,610	)	$	382,104	$	(6,676	)
Remaining Contractual Maturity of Securities	Remaining Contractual Maturity of Securities
	(Amounts in thousands)
		31-Mar-15
		Available-For-Sale Securities						Held-To-Maturity Securities
		Amortized			Fair			Amortized			Fair
		Cost			Value			Cost			Value
	U.S. Treasury, U.S. Agency, state and municipal and foreign sovereign debt securities:
	One year or less	$	7,839		$	7,985		$	816		$	817
	One year to five years	447,192			452,133			253			257
	Five years to ten years	195,714			199,318			—			—
	After ten years	14,335			14,560			—			—
	All other securities:
	Collateralized mortgage obligations	123,181			127,828			58,209			56,936
	Residential mortgage-backed securities	802,921			829,413			909,643			923,368
	Commercial mortgage-backed securities	—			—			190,932			192,024
	Total	$	1,591,182		$	1,631,237		$	1,159,853		$	1,173,402
Securities Gains (Losses)	Securities Gains (Losses)
	(Amounts in thousands)
		Quarter Ended March 31,
		2015			2014
	Proceeds from sales	$	28,931		$	47,477
	Gross realized gains	$	538		$	397
	Gross realized losses	(4		)	(66		)
	Net realized gains	$	534		$	331
	Income tax provision on net realized gains	$	210		$	131

LOANS_AND_CREDIT_QUALITY_Table

LOANS AND CREDIT QUALITY (Tables)	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Loan Portfolio	Loan Portfolio
	(Amounts in thousands)
		March 31,				December 31,
		2015				2014
	Commercial and industrial	$	6,213,029			$	5,996,070
	Commercial - owner-occupied CRE	1,977,601				1,892,564
	Total commercial	8,190,630				7,888,634
	Commercial real estate	2,411,359				2,323,616
	Commercial real estate - multi-family	492,695				593,103
	Total commercial real estate	2,904,054				2,916,719
	Construction	357,258				381,102
	Residential real estate	376,741				361,565
	Home equity	138,734				142,177
	Personal	203,067				202,022
	Total loans	$	12,170,484			$	11,892,219
	Net deferred loan fees and unamortized discount and premium on loans, included as a reduction in total loans	$	46,862			$	47,017
	Overdrawn demand deposits included in total loans	$	1,540			$	1,963
Loans Held-for-sale	Loans Held-For-Sale
	(Amounts in thousands)
		March 31,				December 31,
		2015				2014
	Mortgage loans held-for-sale (1)	$	21,866			$	42,215
	Other loans held-for-sale (2)	67,595				72,946
	Total loans held-for-sale	$	89,461			$	115,161
	(1)	Comprised of residential mortgage loan originations intended to be sold in the secondary market. The Company accounts for these loans under the fair value option. Refer to Note 16 for additional information regarding mortgage loans held-for-sale.
	(2)	Amounts at March 31, 2015 represent commercial, commercial real estate, and construction loans carried at the lower of aggregate cost or fair value. Generally, the Company intends to sell these loans within 30-60 days from the date the intent to sell was established. Amounts at December 31, 2014 consists of $36.6 million of commercial, commercial real estate and construction loans carried at the lower of aggregate cost or fair value and $36.3 million of commercial, commercial real estate, construction, home equity and personal loans held-for-sale in connection with the sale of the Company's banking office located in Norcross, Georgia, which closed in January 2015.
Carrying Value Of Loans Pledged	Carrying Value of Loans Pledged
	(Amounts in thousands)
		March 31,				December 31,
		2015				2014
	Loans pledged to secure outstanding borrowings or availability:
	FRB discount window borrowings (1)	$	458,615			$	478,692
	FHLB advances (2)	1,851,727				1,576,168
	Total	$	2,310,342			$	2,054,860
	(1)	No borrowings were outstanding at March 31, 2015 or December 31, 2014.
	(2)	Refer to Notes 7 and 8 for additional information regarding FHLB advances.
Loan Portfolio Aging	Loan Portfolio Aging																									[1]
	(Amounts in thousands)
						Delinquent
		Current				30 – 59				60 – 89			90 Days Past				Total				Nonaccrual			Total Loans
						Days Past Due				Days Past Due			Due and				Accruing
													Accruing				Loans
	As of March 31, 2015
	Commercial	$	8,147,503			$	1,862			$	2,292		$	—			$	8,151,657			$	38,973		$	8,190,630
	Commercial real estate	2,888,347				88				—			—				2,888,435				15,619			2,904,054
	Construction	356,308				950				—			—				357,258				—			357,258
	Residential real estate	368,824				2,912				242			—				371,978				4,763			376,741
	Home equity	126,575				814				—			—				127,389				11,345			138,734
	Personal	202,692				47				10			—				202,749				318			203,067
	Total loans	$	12,090,249			$	6,673			$	2,544		$	—			$	12,099,466			$	71,018		$	12,170,484
	As of December 31, 2014
	Commercial	$	7,855,833			$	762			$	992		$	—			$	7,857,587			$	31,047		$	7,888,634
	Commercial real estate	2,891,301				5,408				261			—				2,896,970				19,749			2,916,719
	Construction	380,939				163				—			—				381,102				—			381,102
	Residential real estate	354,717				943				631			—				356,291				5,274			361,565
	Home equity	128,500				397				2,236			—				131,133				11,044			142,177
	Personal	201,569				23				—			—				201,592				430			202,022
	Total loans	$	11,812,859			$	7,696			$	4,120		$	—			$	11,824,675			$	67,544		$	11,892,219
Impaired Loans	Impaired Loans
	(Amounts in thousands)
		Unpaid				Recorded				Recorded			Total				Specific
		Contractual				Investment				Investment			Recorded				Reserve
		Principal				With No				With			Investment
		Balance				Specific				Specific
						Reserve				Reserve
	As of March 31, 2015
	Commercial	$	70,501			$	31,582			$	28,166		$	59,748			$	10,643
	Commercial real estate	22,385				6,020				9,776			15,796				2,201
	Residential real estate	5,344				—				4,763			4,763				430
	Home equity	13,425				3,651				9,110			12,761				2,292
	Personal	318				—				318			318				70
	Total impaired loans	$	111,973			$	41,253			$	52,133		$	93,386			$	15,636
	As of December 31, 2014
	Commercial	$	60,174			$	25,739			$	26,432		$	52,171			$	11,487
	Commercial real estate	26,738				9,755				10,193			19,948				2,441
	Residential real estate	5,849				349				4,925			5,274				735
	Home equity	12,904				3,627				8,839			12,466				1,855
	Personal	430				—				430			430				109
	Total impaired loans	$	106,095			$	39,470			$	50,819		$	90,289			$	16,627
Average Recorded Investment And Interest Income Recognized On Impaired Loans	Average Recorded Investment and Interest Income Recognized on Impaired Loans (1)																									[1]
	(Amounts in thousands)
		Quarter Ended March 31,
		2015								2014
		Average				Interest				Average			Interest
		Recorded				Income				Recorded			Income
		Investment				Recognized				Investment			Recognized
	Commercial	$	53,048			$	184			$	43,777		$	382
	Commercial real estate	17,897				3				46,415			24
	Residential real estate	4,979				—				9,833			—
	Home equity	13,332				22				13,526			24
	Personal	356				—				663			—
	Total	$	89,612			$	209			$	114,214		$	430
	(1)	Represents amounts while classified as impaired for the periods presented.
Credit Quality Indicators	Credit Quality Indicators																									[1]
	(Dollars in thousands)
		Special				% of			Potential			% of			Non-				% of			Total Loans
		Mention				Portfolio			Problem			Portfolio			Performing				Portfolio
						Loan			Loans			Loan			Loans				Loan
						Type						Type							Type
	As of March 31, 2015
	Commercial	$	97,851			1.2			$	95,448		1.2			$	38,973			0.5			$	8,190,630
	Commercial real estate	130				*			2,925			0.1			15,619				0.5			2,904,054
	Construction	—				—			—			—			—				—			357,258
	Residential real estate	3,323				0.9			6,045			1.6			4,763				1.3			376,741
	Home equity	502				0.4			2,599			1.9			11,345				8.2			138,734
	Personal	845				0.4			21			*			318				0.2			203,067
	Total	$	102,651			0.8			$	107,038		0.9			$	71,018			0.6			$	12,170,484
	As of December 31, 2014
	Commercial	$	93,130			1.2			$	78,562		1			$	31,047			0.4			$	7,888,634
	Commercial real estate	3,552				0.1			746			*			19,749				0.7			2,916,719
	Construction	—				—			—			—			—				—			381,102
	Residential real estate	2,964				0.8			5,981			1.7			5,274				1.5			361,565
	Home equity	1,170				0.8			2,108			1.5			11,044				7.8			142,177
	Personal	173				0.1			45			*			430				0.2			202,022
	Total	$	100,989			0.8			$	87,442		0.7			$	67,544			0.6			$	11,892,219
	*	Less than 0.1%
Troubled Debt Restructured Loans Outstanding	Troubled Debt Restructured Loans Outstanding
	(Amounts in thousands)
		31-Mar-15								31-Dec-14
		Accruing				Nonaccrual (1)				Accruing			Nonaccrual (1)
	Commercial	$	20,775			$	17,333			$	21,124		$	20,113
	Commercial real estate	177				12,335				199			8,005
	Residential real estate	—				1,737				—			1,881
	Home equity	1,416				5,701				1,422			5,886
	Personal	—				284				—			413
	Total	$	22,368			$	37,390			$	22,745		$	36,298
	(1)	Included in nonperforming loans.
Additions To TDR During The Period	Additions to Troubled Debt Restructurings During the Period
	(Dollars in thousands)
		Quarter Ended March 31,
		2015										2014
		Number of			Recorded Investment (1)							Number of			Recorded Investment (1)
		Borrowers			Pre-				Post-			Borrowers			Pre-				Post-
					Modification				Modification						Modification				Modification
	Accruing TDRs
	Commercial
	Extension of maturity date (2)	1			$	2,394			$	2,394		1			$	200			$	200
	Other concession (3)	—			—				—			1			12,941				12,941
	Total commercial	1			2,394				2,394			2			13,141				13,141
	Commercial real estate
	Other concession (3)	—			—				—			1			426				426
	Total accruing	1			$	2,394			$	2,394		3			$	13,567			$	13,567
	Nonaccrual TDRs
	Commercial
	Other concession (3)	1			$	673			$	666		2			$	456			$	406
	Commercial real estate
	Extension of maturity date (2)	2			1,747				1,660			—			—				—
	Other concession (3)	1			3,773				3,773			—			—				—
	Total commercial real estate	3			5,520				5,433			—			—				—
	Residential real estate
	Other concession (3)	—			—				—			2			495				495
	Home equity
	Extension of maturity date (2)	—			—				—			1			114				114
	Other concession (3)	2			77				77			1			250				250
	Total home equity	2			77				77			2			364				364
	Total nonaccrual	6			$	6,270			$	6,176		6			$	1,315			$	1,265
	Change in recorded investment due to principal paydown at time of modification								$	94									$	50
	(1)	Represents amounts as of the date immediately prior to and immediately after the modification is effective.
	(2)	Extension of maturity date also includes loans renewed at existing rate of interest which is considered a below market rate for that particular loan’s risk profile.
	(3)	Other concessions primarily include interest rate reductions, loan increases or deferrals of principal.
OREO Composition	OREO Composition
	(Amounts in thousands)
		31-Mar-15				31-Dec-14
	Single-family homes	$	7,698			$	7,902
	Land parcels	3,971				4,237
	Multi-family	465				488
	Office/industrial	2,663				3,832
	Retail	828				957
	Total OREO properties	$	15,625			$	17,416
Covered Assets	Covered Assets
	(Amounts in thousands)
		March 31, 2015				December 31, 2014
	Residential mortgage loans (1)	$	29,963			$	32,182
	Foreclosed real estate - single family homes	203				187
	Estimated loss reimbursement by the FDIC	2,025				1,763
	Total covered assets	32,191				34,132
	Allowance for covered loan losses	(6,021		)		(5,191		)
	Net covered assets	$	26,170			$	28,941
	(1)	Includes $266,000 and $420,000 of purchased impaired loans as of March 31, 2015 and December 31, 2014, respectively.
[1]	Extension of maturity date also includes loans renewed at existing rate of interest which is considered a below market rate for that particular loan’s risk profile.

ALLOWANCE_FOR_LOAN_LOSSES_AND_1

ALLOWANCE FOR LOAN LOSSES AND RESERVE FOR UNFUNDED COMMITMENTS (Tables)	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Allowance For Loan Losses and Recorded Investment in Loans	Allowance for Loan Losses and Recorded Investment in Loans																						[1]
	(Amounts in thousands)
		Quarter Ended March 31, 2015
		Commercial			Commercial			Construction			Residential			Home			Personal			Total
					Real						Real			Equity
					Estate						Estate
	Allowance for Loan Losses:
	Balance at beginning of period	$	103,462		$	31,838		$	4,290		$	5,316		$	4,924		$	2,668		$	152,498
	Loans charged-off	(2,202		)	(887		)	—			(37		)	(371		)	(10		)	(3,507		)
	Recoveries on loans previously charged-off	511			598			19			57			70			873			2,128
	Net (charge-offs) recoveries	(1,691		)	(289		)	19			20			(301		)	863			(1,379		)
	Provision (release) for loan losses	7,102			57			(283		)	(113		)	(35		)	(1,237		)	5,491
	Balance at end of period	$	108,873		$	31,606		$	4,026		$	5,223		$	4,588		$	2,294		$	156,610
	Ending balance, loans individually evaluated for impairment (1)	$	10,643		$	2,201		$	—		$	430		$	2,292		$	70		$	15,636
	Ending balance, loans collectively evaluated for impairment	$	98,230		$	29,405		$	4,026		$	4,793		$	2,296		$	2,224		$	140,974
	Recorded Investment in Loans:
	Ending balance, loans individually evaluated for impairment (1)	$	59,748		$	15,796		$	—		$	4,763		$	12,761		$	318		$	93,386
	Ending balance, loans collectively evaluated for impairment	8,130,882			2,888,258			357,258			371,978			125,973			202,749			12,077,098
	Total recorded investment in loans	$	8,190,630		$	2,904,054		$	357,258		$	376,741		$	138,734		$	203,067		$	12,170,484
	(1)	Refer to Note 4 for additional information regarding impaired loans.
	Allowance for Loan Losses and Recorded Investment in Loans (Continued)
	(Amounts in thousands)
		Quarter Ended March 31, 2014
		Commercial			Commercial			Construction			Residential			Home			Personal			Total
					Real						Real			Equity
					Estate						Estate
	Allowance for Loan Losses:
	Balance at beginning of period	$	80,768		$	42,362		$	3,338		$	7,555		$	5,648		$	3,438		$	143,109
	Loans charged-off	(1,487		)	(2,582		)	—			(235		)	(447		)	(130		)	(4,881		)
	Recoveries on loans previously charged-off	3,662			688			7			300			28			406			5,091
	Net recoveries (charge-offs)	2,175			(1,894		)	7			65			(419		)	276			210
	Provision (release) for loan losses	7,137			(2,893		)	202			(642		)	271			(626		)	3,449
	Balance at end of period	$	90,080		$	37,575		$	3,547		$	6,978		$	5,500		$	3,088		$	146,768
	Ending balance, loans individually evaluated for impairment (1)	$	8,678		$	9,479		$	—		$	2,198		$	2,274		$	138		$	22,767
	Ending balance, loans collectively evaluated for impairment	$	81,402		$	28,096		$	3,547		$	4,780		$	3,226		$	2,950		$	124,001
	Recorded Investment in Loans:
	Ending balance, loans individually evaluated for impairment (1)	$	54,700		$	42,180		$	—		$	9,354		$	13,430		$	625		$	120,289
	Ending balance, loans collectively evaluated for impairment	7,342,248			2,457,226			335,476			328,478			134,144			207,124			10,804,696
	Total recorded investment in loans	$	7,396,948		$	2,499,406		$	335,476		$	337,832		$	147,574		$	207,749		$	10,924,985
	(1)	Refer to Note 4 for additional information regarding impaired loans.
Reserve For Unfunded Commitments	Reserve for Unfunded Commitments (1)																						[1]
	(Amounts in thousands)
		Quarter Ended March 31,
		2015			2014
	Balance at beginning of period	$	12,274		$	9,206
	Provision for unfunded commitments	376			496
	Balance at end of period	$	12,650		$	9,702
	Unfunded commitments, excluding covered assets, at period end	$	6,229,242		$	4,814,346
	(1)	Unfunded commitments include commitments to extend credit, standby letters of credit and commercial letters of credit. Unfunded commitments related to covered assets are excluded as they are covered under a loss sharing agreement with the FDIC.
[1]	Refer to Note 4 for additional information regarding impaired loans.

GOODWILL_AND_OTHER_INTANGIBLE_1

GOODWILL AND OTHER INTANGIBLE ASSETS (Tables)	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Carrying Amount Of Goodwill By Operating Segment	Carrying Amount of Goodwill by Operating Segment
	(Amounts in thousands)
		March 31,		31-Dec-14
		2015
	Banking	$	81,755	$	81,755
	Asset management	12,286		12,286
	Total goodwill	$	94,041	$	94,041
Other Intangible Assets	Other Intangible Assets
	(Dollars in thousands)
		Quarter Ended March 31, 2015		Year Ended December 31, 2014
	Core deposit intangibles:
	Gross carrying amount	$	18,093	$	18,093
	Accumulated amortization	13,473		12,870
	Net carrying amount	$	4,620	$	5,223
	Amortization during the period	$	603	$	2,799
	Weighted average remaining life (in years)	2		2
	Client relationships:
	Gross carrying amount	$	2,002	$	2,002
	Accumulated amortization	1,392		1,340
	Net carrying amount	$	610	$	662
	Amortization during the period	$	52	$	208
	Weighted average remaining life (in years)	6		6
Scheduled Amortization Of Other Intangible Assets	Scheduled Amortization of Other Intangible Assets
	(Amounts in thousands)
		Total
	Year ending December 31,
	2015 - remaining nine months	$	1,800
	2016	2,161
	2017	1,125
	2018	98
	2019	28
	2020 and thereafter	18
	Total	$	5,230

SHORTTERM_AND_SECURED_BORROWIN1

SHORT-TERM AND SECURED BORROWINGS (Tables)	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Summary Of Short-Term Borrowings	Summary of Short-Term Borrowings
	(Dollars in thousands)
		31-Mar-15				31-Dec-14
		Amount		Rate		Amount		Rate
	Outstanding:
	FHLB advances	$	253,000	0.14	%	$	428,000	0.13	%
	Other borrowings	33		0.06	%	—		—	%
	Total short-term borrowings	$	253,033			$	428,000
	Other Information:
	Weighted average remaining maturity of FHLB advances at period end	9 months				7 months
	Unused FHLB advances availability	$	552,721			$	265,529
	Unused overnight Federal funds availability (1)	$	630,500			$	630,500
	Borrowing capacity through the FRB discount window primary credit program (2)	$	392,842			$	403,752
	(1)	Our total availability of overnight Federal fund borrowings is not a committed line of credit and is dependent upon lender availability.
	(2)	Our borrowing capacity changes each quarter subject to available collateral and FRB discount factors.

LONGTERM_DEBT_LongTerm_Debt_Ta

LONG-TERM DEBT Long-Term Debt (Tables)	3 Months Ended
	Mar. 31, 2015
Long-term Debt, Unclassified [Abstract]
Long-term Debt [Table Text Block]	Long-Term Debt
	(Dollars in thousands)
					March 31,		December 31,
					2015		2014
	Parent Company:
	2.92% junior subordinated debentures due 2034		(1)(a)		$	8,248	$	8,248
	1.98% junior subordinated debentures due 2035		(2)(a)		51,547		51,547
	1.77% junior subordinated debentures due 2035		(3)(a)		41,238		41,238
	10.00% junior subordinated debentures due 2068			(a)	68,755		68,755
	7.125% subordinated debentures due 2042	(b)			125,000		125,000
	Subtotal				294,788		294,788
	Subsidiaries:
	FHLB advances				50,000		50,000
	Total long-term debt				$	344,788	$	344,788
	(1)	Variable rate in effect at March 31, 2015 based on three-month LIBOR +2.65%.
	(2)	Variable rate in effect at March 31, 2015, based on three-month LIBOR +1.71%.
	(3)	Variable rate in effect at March 31, 2015, based on three-month LIBOR +1.50%.
	(a)	Under the final regulatory capital rules issued in July 2013, these instruments are grandfathered for inclusion as a component of Tier 1 capital, although the Tier 1 capital treatment for these instruments will be subject to phase-out due to certain acquisitions.
	(b)	Qualifies as Tier 2 capital for regulatory capital purposes.
Maturity and Rate Schedule for FHLB Long-Term Advances [Table Text Block]	Maturity and Rate Schedule for FHLB Long-Term Advances
	(Dollars in thousands)
		31-Mar-15
		Amount			Rate
	Maturity Date:
	March 25, 2019	$	2,000		4.26	%
	May 22, 2019	3,000			4.68	%
	September 12, 2019 (1)	15,000			3.72	%
	September 26, 2019 (1)	15,000			3.69	%
	December 9, 2019 (2)	15,000			3.58	%
	Total	$	50,000		3.75	%
	(1)	Provides for a one-time option to increase the advances in September 2016, up to $150.0 million each at the same fixed rate as the original advance. The advances include prepayment features and are subject to a prepayment fee.
	(2)	Provides for a one-time option to increase the advances in December 2016, up to $150.0 million each at the same fixed rate as the original advance. The advances include prepayment features and are subject to a prepayment fee.
Scheduled Maturities of Long-Term Debt [Table Text Block]	Scheduled Maturities of Long-Term Debt
	(Amounts in thousands)
		Total
	Year ending December 31,
	2019	$	50,000
	2020 and thereafter	294,788
	Total	$	344,788

JUNIOR_SUBORDINATED_DEFERRABLE1

JUNIOR SUBORDINATED DEFERRABLE INTEREST DEBENTURES HELD BY TRUSTS THAT ISSUED GUARANTEED CAPITAL DEBT SECURITIES (Tables)	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Common Securities, Preferred Securities, And Related Debentures	Common Securities, Preferred Securities, and Related Debentures
	(Dollars in thousands)
			Common Securities Issued		Trust Preferred Securities				Earliest Redemption Date (on or after) (3)		Principal Amount of
					Issued (1)						Debentures (3)
		Issuance					Coupon			Maturity	March 31,		December 31,
		Date					Rate (2)				2015		2014
	Bloomfield Hills Statutory Trust I	May 2004	$	248	$	8,000	2.92	%	June 17, 2009	Jun-34	$	8,248	$	8,248
	PrivateBancorp Statutory Trust II	Jun. 2005	1,547		50,000		1.98	%	Sep 15, 2010	Sept. 2035	51,547		51,547
	PrivateBancorp Statutory Trust III	Dec. 2005	1,238		40,000		1.77	%	Dec 15, 2010	Dec. 2035	41,238		41,238
	PrivateBancorp Capital Trust IV	May 2008	5		68,750		10	%	June 15, 2013	Jun-68	68,755		68,755
	Total		$	3,038	$	166,750					$	169,788	$	169,788
	(1)	The trust preferred securities accrue distributions at a rate equal to the interest rate on and have a maturity identical to that of the related Debentures. The trust preferred securities will be redeemed upon maturity or earlier redemption of the related Debentures.
	(2)	Reflects the coupon rate in effect at March 31, 2015. The coupon rate for the Bloomfield Hills Statutory Trust I is a variable rate and is based on three-month LIBOR plus 2.65%. The coupon rates for the PrivateBancorp Statutory Trusts II and III are at a variable rate based on three-month LIBOR plus 1.71% for Trust II and three-month LIBOR plus 1.50% for Trust III. The coupon rate for the PrivateBancorp Capital Trust IV is fixed. Distributions for all of the Trusts are payable quarterly. We have the right to defer payment of interest on the Debentures at any time or from time to time for a period not exceeding ten years in the case of the Debentures held by Trust IV, and five years in the case of all other Debentures, without causing an event of default under the related indenture, provided no extension period may extend beyond the stated maturity of the Debentures. During such extension period, distributions on the trust preferred securities would also be deferred, and our ability to pay dividends on our common stock would generally be prohibited. The Federal Reserve has the ability to prevent interest payments on the Debentures.
	(3)	The trust preferred securities are subject to mandatory redemption, in whole or in part, upon repayment of the Debentures at maturity or upon their earlier redemption in whole or in part. The Debentures are redeemable in whole or in part prior to maturity at any time after the dates shown in the table and only after we have obtained Federal Reserve approval, if then required under applicable guidelines or regulations.

EQUITY_Tables

EQUITY (Tables)	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Change in Accumulated Other Comprehensive Income by Component	Change in Accumulated Other Comprehensive Income ("AOCI") by Component
	(Amounts in thousands)
		Quarter Ended March 31,
		2015									2014
		Unrealized Gain on Available-for-Sale Securities			Accumulated			Total			Unrealized Gain on Available-for-Sale Securities			Accumulated			Total
					(Loss) Gain on Effective									(Loss) Gain on Effective
					Cash Flow									Cash Flow
					Hedges									Hedges
	Balance at beginning of period	$	19,448		$	1,469		$	20,917		$	12,960		$	(3,116	)	$	9,844
	Increase in unrealized gains on securities	8,590			—			8,590			3,677			—			3,677
	Increase in unrealized gains on cash flow hedges	—			8,630			8,630			—			4,137			4,137
	Tax expense on increase in unrealized gains	(3,358		)	(3,369		)	(6,727		)	(1,451		)	(1,623		)	(3,074		)
	Other comprehensive income before reclassifications	5,232			5,261			10,493			2,226			2,514			4,740
	Reclassification adjustment of net gains included in net income (1)	(534		)	(2,538		)	(3,072		)	(331		)	(2,043		)	(2,374		)
	Reclassification adjustment for tax expense on realized net gains (2)	210			999			1,209			131			806			937
	Amounts reclassified from AOCI	(324		)	(1,539		)	(1,863		)	(200		)	(1,237		)	(1,437		)
	Net current period other comprehensive income	4,908			3,722			8,630			2,026			1,277			3,303
	Balance at end of period	$	24,356		$	5,191		$	29,547		$	14,986		$	(1,839	)	$	13,147
	(1)	The amounts reclassified from AOCI for the available-for-sale securities are included in net securities gains on the Consolidated Statements of Income, while the amounts reclassified from AOCI for cash flow hedges are included in interest income on loans on the Consolidated Statements of Income.
	(2)	The tax expense amounts reclassified from AOCI in connection with the available-for-sale securities reclassification and cash flow hedges reclassification are included in income tax provision on the Consolidated Statements of Income.

EARNINGS_PER_COMMON_SHARE_Tabl

EARNINGS PER COMMON SHARE (Tables)	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Basic and Diluted Earnings Per Common Share	Basic and Diluted Earnings per Common Share
	(Amounts in thousands, except per share data)
		Quarter Ended March 31,
		2015			2014
	Basic earnings per common share
	Net income	$	41,484		$	34,505
	Net income allocated to participating stockholders (1)	(463		)	(613		)
	Net income allocated to common stockholders	$	41,021		$	33,892
	Weighted-average common shares outstanding	77,407			76,675
	Basic earnings per common share	$	0.53		$	0.44
	Diluted earnings per common share
	Diluted earnings applicable to common stockholders (2)	$	41,028		$	33,897
	Weighted-average diluted common shares outstanding:
	Weighted-average common shares outstanding	77,407			76,675
	Dilutive effect of stock awards (3)	1,105			742
	Weighted-average diluted common shares outstanding	78,512			77,417
	Diluted earnings per common share	$	0.52		$	0.44
	(1)	Participating stockholders are those that hold certain share-based payment awards that contain nonforfeitable rights to dividends or dividend equivalents. Such shares or units are considered participating securities (i.e., certain of the Company’s deferred and restricted stock units and nonvested restricted stock awards).
	(2)	Net income allocated to common stockholders for basic and diluted earnings per share may differ under the two-class method as a result of adding common stock equivalents for options to dilutive shares outstanding, which alters the ratio used to allocate earnings to common stockholders and participating securities for the purposes of calculating diluted earnings per share.
	(3)	For the quarters ended March 31, 2015 and 2014, the weighted-average outstanding non-participating securities of 730,000 and 1.2 million shares, respectively, were not included in the computation of diluted earnings per common share because their inclusion would have been antidilutive for the periods presented.

INCOME_TAXES_Tables

INCOME TAXES (Tables)	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Income Tax Provision Analysis	Income Tax Provision Analysis
	(Dollars in thousands)
		Quarter Ended
		March 31,
		2015			2014
	Income before income taxes	$	66,718		$	55,531
	Income tax provision:
	Current income tax provision	$	21,540		$	19,867
	Deferred income tax provision	3,694			1,159
	Total income tax provision	$	25,234		$	21,026
	Effective tax rate	37.8		%	37.9		%

DERIVATIVE_INSTRUMENTS_Tables

DERIVATIVE INSTRUMENTS (Tables)	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Notional Amounts and Fair Value Of Derivative Instruments	Notional Amounts and Fair Value of Derivative Instruments
	(Amounts in thousands)
		Asset Derivatives												Liability Derivatives
		31-Mar-15						31-Dec-14						31-Mar-15					31-Dec-14
		Notional (1)			Fair			Notional (1)			Fair			Notional (1)		Fair			Notional (1)		Fair
					Value						Value					Value					Value
	Derivatives designated as hedging instruments:
	Interest rate contracts	$	725,000		$	8,491		$	550,000		$	4,542		$	75,000	$	441		$	250,000	$	2,715
	Derivatives not designated as hedging instruments:
	Client-related derivatives:
	Interest rate contracts	$	3,982,438		$	54,821		$	3,881,202		$	42,879		$	3,982,438	$	56,520		$	3,743,827	$	43,792
	Foreign exchange contracts	173,672			9,056			98,285			5,183			149,430		8,433			86,582		4,659
	Credit contracts (1)	94,241			20			98,478			19			110,426		26			100,941		24
	Total client-related derivatives				$	63,897					$	48,081				$	64,979				$	48,475
	Other end-user derivatives:
	Foreign exchange contracts	$	10,937		$	115		$	18,551		$	241		$	4,566	$	18		$	2,892	$	45
	Mortgage banking derivatives				479						786					534					801
	Total other end-user derivatives				$	594					$	1,027				$	552				$	846
	Total derivatives not designated as hedging instruments				$	64,491					$	49,108				$	65,531				$	49,321
	Netting adjustments (2)				(16,375		)				(10,588		)			(39,005		)			(25,269		)
	Total derivatives				$	56,607					$	43,062				$	26,967				$	26,767
	(1)	The remaining average notional amounts are shown for credit contracts.
	(2)	Represents netting of derivative asset and liability balances, and related cash collateral, with the same counterparty subject to master netting agreements.
Offsetting Liabilities	Offsetting of Derivative Assets and Liabilities
	(Amounts in thousands)
		Gross Amounts of Recognized Assets / Liabilities (1)			Gross Amounts Offset (2)			Net Amount Presented on the Statement of Financial Condition			Gross Amounts Not Offset on the Statement of Financial Condition (3)					Net Amount
											Financial Instruments (4)			Cash Collateral
	As of March 31, 2015
	Derivative assets:
	Interest rate contracts	$	63,312		$	(10,462	)	$	52,850		$	(721	)	$	—	$	52,129
	Foreign exchange contracts	6,508			(5,912		)	596			—			—		596
	Credit contracts	20			(1		)	19			—			—		19
	Total derivatives subject to a master netting agreement	69,840			(16,375		)	53,465			(721		)	—		52,744
	Total derivatives not subject to a master netting agreement	3,142			—			3,142			—			—		3,142
	Total derivatives	$	72,982		$	(16,375	)	$	56,607		$	(721	)	$	—	$	55,886
	Derivative liabilities:
	Interest rate contracts	$	56,961		$	(36,426	)	$	20,535		$	(15,482	)	$	—	$	5,053
	Foreign exchange contracts	5,041			(2,570		)	2,471			(1,863		)	—		608
	Credit contracts	26			(9		)	17			(13		)	—		4
	Total derivatives subject to a master netting agreement	62,028			(39,005		)	23,023			(17,358		)	—		5,665
	Total derivatives not subject to a master netting agreement	3,944			—			3,944			—			—		3,944
	Total derivatives	$	65,972		$	(39,005	)	$	26,967		$	(17,358	)	$	—	$	9,609
	(1)	All derivative contracts are over-the-counter contracts.
	(2)	Represents end-user, client-related and cash flow hedging derivative contracts and related cash collateral entered into with the same counterparty and subject to a master netting agreement.
	(3)	Collateralization is determined at the counterparty level. If overcollateralization exists, the amount shown is limited to the fair value of the derivative.
	(4)	Financial instruments are disclosed at fair value. Financial instrument collateral is allocated pro-rata amongst the derivative liabilities to which it relates.
	Offsetting of Derivative Assets and Liabilities (Continued)
	(Amounts in thousands)
		Gross Amounts of Recognized Assets / Liabilities (1)			Gross Amounts Offset (2)			Net Amount Presented on the Statement of Financial Condition			Gross Amounts Not Offset on the Statement of Financial Condition (3)					Net Amount
											Financial Instruments (4)			Cash Collateral
	As of December 31, 2014
	Derivative assets:
	Interest rate contracts	$	47,421		$	(7,433	)	$	39,988		$	—		$	—	$	39,988
	Foreign exchange contracts	3,664			(3,154		)	510			—			—		510
	Credit contracts	19			(1		)	18			—			—		18
	Total derivatives subject to a master netting agreement	51,104			(10,588		)	40,516			—			—		40,516
	Total derivatives not subject to a master netting agreement	2,546			—			2,546			—			—		2,546
	Total derivatives	$	53,650		$	(10,588	)	$	43,062		$	—		$	—	$	43,062
	Derivative liabilities:
	Interest rate contracts	$	46,507		$	(24,067	)	$	22,440		$	(17,755	)	$	—	$	4,685
	Foreign exchange contracts	2,421			(1,202		)	1,219			(965		)	—		254
	Credit contracts	24			—			24			(19		)	—		5
	Total derivatives subject to a master netting agreement	48,952			(25,269		)	23,683			(18,739		)	—		4,944
	Total derivatives not subject to a master netting agreement	3,084			—			3,084			—			—		3,084
	Total derivatives	$	52,036		$	(25,269	)	$	26,767		$	(18,739	)	$	—	$	8,028
	(1)	All derivative contracts are over-the-counter contracts.
	(2)	Represents end-user, client-related and cash flow hedging derivative contracts entered into with the same counterparty and subject to a master netting agreement.
	(3)	Collateralization is determined at the counterparty level. If overcollateralization exists, the amount shown is limited to the fair value of the derivative.
	(4)	Financial instruments are disclosed at fair value. Financial instrument collateral is allocated pro-rata amongst the derivative liabilities to which it relates.
Offsetting Assets	Offsetting of Derivative Assets and Liabilities
	(Amounts in thousands)
		Gross Amounts of Recognized Assets / Liabilities (1)			Gross Amounts Offset (2)			Net Amount Presented on the Statement of Financial Condition			Gross Amounts Not Offset on the Statement of Financial Condition (3)					Net Amount
											Financial Instruments (4)			Cash Collateral
	As of March 31, 2015
	Derivative assets:
	Interest rate contracts	$	63,312		$	(10,462	)	$	52,850		$	(721	)	$	—	$	52,129
	Foreign exchange contracts	6,508			(5,912		)	596			—			—		596
	Credit contracts	20			(1		)	19			—			—		19
	Total derivatives subject to a master netting agreement	69,840			(16,375		)	53,465			(721		)	—		52,744
	Total derivatives not subject to a master netting agreement	3,142			—			3,142			—			—		3,142
	Total derivatives	$	72,982		$	(16,375	)	$	56,607		$	(721	)	$	—	$	55,886
	Derivative liabilities:
	Interest rate contracts	$	56,961		$	(36,426	)	$	20,535		$	(15,482	)	$	—	$	5,053
	Foreign exchange contracts	5,041			(2,570		)	2,471			(1,863		)	—		608
	Credit contracts	26			(9		)	17			(13		)	—		4
	Total derivatives subject to a master netting agreement	62,028			(39,005		)	23,023			(17,358		)	—		5,665
	Total derivatives not subject to a master netting agreement	3,944			—			3,944			—			—		3,944
	Total derivatives	$	65,972		$	(39,005	)	$	26,967		$	(17,358	)	$	—	$	9,609
	(1)	All derivative contracts are over-the-counter contracts.
	(2)	Represents end-user, client-related and cash flow hedging derivative contracts and related cash collateral entered into with the same counterparty and subject to a master netting agreement.
	(3)	Collateralization is determined at the counterparty level. If overcollateralization exists, the amount shown is limited to the fair value of the derivative.
	(4)	Financial instruments are disclosed at fair value. Financial instrument collateral is allocated pro-rata amongst the derivative liabilities to which it relates.
	Offsetting of Derivative Assets and Liabilities (Continued)
	(Amounts in thousands)
		Gross Amounts of Recognized Assets / Liabilities (1)			Gross Amounts Offset (2)			Net Amount Presented on the Statement of Financial Condition			Gross Amounts Not Offset on the Statement of Financial Condition (3)					Net Amount
											Financial Instruments (4)			Cash Collateral
	As of December 31, 2014
	Derivative assets:
	Interest rate contracts	$	47,421		$	(7,433	)	$	39,988		$	—		$	—	$	39,988
	Foreign exchange contracts	3,664			(3,154		)	510			—			—		510
	Credit contracts	19			(1		)	18			—			—		18
	Total derivatives subject to a master netting agreement	51,104			(10,588		)	40,516			—			—		40,516
	Total derivatives not subject to a master netting agreement	2,546			—			2,546			—			—		2,546
	Total derivatives	$	53,650		$	(10,588	)	$	43,062		$	—		$	—	$	43,062
	Derivative liabilities:
	Interest rate contracts	$	46,507		$	(24,067	)	$	22,440		$	(17,755	)	$	—	$	4,685
	Foreign exchange contracts	2,421			(1,202		)	1,219			(965		)	—		254
	Credit contracts	24			—			24			(19		)	—		5
	Total derivatives subject to a master netting agreement	48,952			(25,269		)	23,683			(18,739		)	—		4,944
	Total derivatives not subject to a master netting agreement	3,084			—			3,084			—			—		3,084
	Total derivatives	$	52,036		$	(25,269	)	$	26,767		$	(18,739	)	$	—	$	8,028
	(1)	All derivative contracts are over-the-counter contracts.
	(2)	Represents end-user, client-related and cash flow hedging derivative contracts entered into with the same counterparty and subject to a master netting agreement.
	(3)	Collateralization is determined at the counterparty level. If overcollateralization exists, the amount shown is limited to the fair value of the derivative.
	(4)	Financial instruments are disclosed at fair value. Financial instrument collateral is allocated pro-rata amongst the derivative liabilities to which it relates.
Derivatives Subject To Credit Risk Contingency Features	Derivatives Subject to Credit Risk Contingency Features
	(Amounts in thousands)
		March 31,			December 31,
		2015			2014
	Fair value of derivatives with credit contingency features in a net liability position	$	13,291		$	14,596
	Collateral posted for those transactions in a net liability position	$	15,226		$	16,865
	If credit risk contingency features were triggered:
	Additional collateral required to be posted to derivative counterparties	$	—		$	—
	Outstanding derivative instruments that would be immediately settled	$	13,291		$	14,596
Change In Accumulated Other Comprehensive Income Related To Interest Rate Swaps Designated As Cash Flow Hedge	Change in Accumulated Other Comprehensive Income
	Related to Interest Rate Swaps Designated as Cash Flow Hedge
	(Amounts in thousands)
		Quarter Ended March 31,
		2015						2014
		Pre-tax			After-tax			Pre-tax			After-tax
	Accumulated unrealized gain (loss) at beginning of period	$	2,405		$	1,469		$	(5,110	)	$	(3,116	)
	Amount of gain recognized in AOCI (effective portion)	8,630			5,261			4,137			2,514
	Amount reclassified from AOCI to interest income on loans	(2,538		)	(1,539		)	(2,043		)	(1,237		)
	Accumulated unrealized gain (loss) at end of period	$	8,497		$	5,191		$	(3,016	)	$	(1,839	)
Risk Participation Agreements	Risk Participation Agreements
	(Dollars in thousands)
		March 31,			December 31,
		2015			2014
	Fair value of written RPAs	$	26		$	24
	Range of remaining terms to maturity (in years)	Less than 1 to 4			Less than 1 to 4
	Range of assigned internal risk ratings	2 to 7			2 to 7
	Maximum potential amount of future undiscounted payments	$	3,821		$	3,927
	Percent of maximum potential amount of future undiscounted payments covered by proceeds from liquidation of pledged collateral	24		%	25		%
Gain (Loss) Recognized On Derivative Instruments Not Designated In Hedging Relationship	Gain (Loss) Recognized on Derivative Instruments
	Not Designated in Hedging Relationship
	(Amounts in thousands)
		Quarter Ended March 31,
		2015			2014
	Gain on client-related derivatives recognized in capital markets products income:
	Interest rate contracts	$	2,363		$	2,510
	Foreign exchange contracts	1,753			1,415
	Credit contracts	56			158
	Total client-related derivatives	4,172			4,083
	Gain (loss) on end-user derivatives recognized in other income:
	Foreign exchange derivatives	1,050			6
	Mortgage banking derivatives	(40		)	(182		)
	Total end-user derivatives	1,010			(176		)
	Total derivatives not designated in hedging relationship	$	5,182		$	3,907

COMMITMENTS_GUARANTEES_AND_CON1

COMMITMENTS, GUARANTEES, AND CONTINGENT LIABILITIES (Tables)	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Contractual Or Notional Amounts Of Financial Instruments	Contractual or Notional Amounts of Financial Instruments (1)
	(Amounts in thousands)
		March 31,		December 31,
		2015		2014
	Commitments to extend credit:
	Home equity lines	$	133,911	$	129,943
	Residential 1-4 family construction	51,776		53,847
	Commercial real estate, other construction, and land development	1,205,048		1,123,123
	Commercial and industrial	4,101,972		4,031,217
	All other commitments	345,133		336,623
	Total commitments to extend credit	$	5,837,840	$	5,674,753
	Letters of credit:
	Financial standby	$	359,716	$	334,175
	Performance standby	37,667		38,167
	Commercial letters of credit	4,765		5,224
	Total letters of credit	$	402,148	$	377,566
	(1)	Includes covered loan commitments of $10.7 million and $11.0 million as of March 31, 2015 and December 31, 2014, respectively.

ESTIMATED_FAIR_VALUE_OF_FINANC1

ESTIMATED FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Fair Value Measurements on a Recurring Basis	Fair Value Measurements on a Recurring Basis
	(Amounts in thousands)
		31-Mar-15															31-Dec-14
		Quoted				Significant				Significant				Total			Quoted		Significant			Significant			Total
		Prices in				Other				Unobservable							Prices in		Other			Unobservable
		Active				Observable				Inputs							Active		Observable			Inputs
		Markets for				Inputs				(Level 3)							Markets for		Inputs			(Level 3)
		Identical				(Level 2)											Identical		(Level 2)
		Assets															Assets
		(Level 1)															(Level 1)
	Assets:
	Securities available-for sale:
	U.S. Treasury	$	244,556			$	—			$	—			$	244,556		$	268,265	$	—		$	—		$	268,265
	U.S. Agency	—				46,806				—				46,806			—		46,258			—			46,258
	Collateralized mortgage obligations	—				127,828				—				127,828			—		136,933			—			136,933
	Residential mortgage-backed securities	—				829,413				—				829,413			—		846,078			—			846,078
	State and municipal securities	—				382,134				—				382,134			—		347,310			—			347,310
	Foreign sovereign debt	—				500				—				500			—		500			—			500
	Total securities available-for-sale	244,556				1,386,681				—				1,631,237			268,265		1,377,079			—			1,645,344
	Mortgage loans held-for-sale	—				21,866				—				21,866			—		42,215			—			42,215
	Derivative assets:
	Interest rate contract derivatives designated as hedging instruments	—				8,491				—				8,491			—		4,542			—			4,542
	Client-related derivatives	—				62,143				1,754				63,897			—		46,669			1,412			48,081
	Other end-user derivatives	—				594				—				594			—		1,027			—			1,027
	Netting adjustments	—				(15,686		)		(689		)		(16,375		)	—		(9,952		)	(636		)	(10,588		)
	Total derivative assets	—				55,542				1,065				56,607			—		42,286			776			43,062
	Total assets	$	244,556			$	1,464,089			$	1,065			$	1,709,710		$	268,265	$	1,461,580		$	776		$	1,730,621
	Liabilities:
	Derivative liabilities:
	Interest rate contract derivatives designated as hedging instruments	$	—			$	441			$	—			$	441		$	—	$	2,715		$	—		$	2,715
	Client-related derivatives	—				64,273				706				64,979			—		47,799			676			48,475
	Other end-user derivatives	—				552				—				552			—		846			—			846
	Netting adjustments	—				(38,316		)		(689		)		(39,005		)	—		(24,633		)	(636		)	(25,269		)
	Total derivative liabilities	$	—			$	26,950			$	17			$	26,967		$	—	$	26,727		$	40		$	26,767
Reconciliation of Beginning and Ending Fair Value for Those Fair Value Measurements Using Significant Unobservable Inputs (Level 3)	Reconciliation of Beginning and Ending Fair Value for Those
	Fair Value Measurements Using Significant Unobservable Inputs (Level 3) (1)
	(Amounts in thousands)
		Quarter Ended March 31,
		2015								2014
		Derivative				Derivative				Derivative				Derivative
		Assets				(Liabilities)				Assets				(Liabilities)
	Balance at beginning of period	$	1,412			$	(676	)		$	448			$	(98	)
	Total gains:
	Included in earnings (2)	312				(24		)		79				180
	Purchases, issuances, sales and settlements:
	Settlements	(500		)		147				(385		)		(245		)
	Transfers into Level 3 (out of Level 2) (3)	884				(160		)		827				(446		)
	Transfers out of Level 3 (into Level 2) (3)	(354		)		8				(112		)		—
	Balance at end of period	$	1,754			$	(705	)		$	857			$	(609	)
	Change in unrealized gains in earnings relating to assets and liabilities still held at end of period	$	241			$	24			$	7			$	166
	(1)	Fair value is presented prior to giving effect to netting adjustments.
	(2)	Amounts disclosed in this line are included in the Consolidated Statements of Income as capital markets products income for derivatives.
	(3)	Transfers in and transfers out are recognized at the end of each quarterly reporting period. In general, derivative assets and liabilities are transferred into Level 3 from Level 2 due to a lack of observable market data, as there was deterioration in the credit risk of the derivative counterparty. Conversely, derivative assets and liabilities are transferred out of Level 3 into Level 2 due to an improvement in the credit risk of the derivative counterparty.
Difference Between Aggregate Fair Value And Aggregate Remaining Principle Balance For Mortgage Loans Held For Sale Elected To Be Carried At Fair Value	Difference Between Aggregate Fair Value and Aggregate Remaining Principal Balance
	for Mortgage Loans Held-For-Sale Elected to be Carried at Fair Value
	(Amounts in thousands)
		March 31,				December 31,
		2015				2014
	Aggregate fair value	$	21,866			$	42,215
	Difference (1)	(55		)		(16		)
	Aggregate unpaid principal balance	$	21,811			$	42,199
	(1)	The change in fair value is reflected in mortgage banking non-interest income.
Fair Value Measurements on a Nonrecurring Basis	All fair value measurements on a nonrecurring basis were measured using level 3 of the valuation hierarchy.
	Fair Value Measurements on a Nonrecurring Basis
	(Amounts in thousands)
		Fair Value								Net (Gains) Losses
		March 31,								For the Quarter Ended March 31,
		2015				2014				2015				2014
	Collateral-dependent impaired loans (1)	$	27,234			$	40,716			$	(1,653	)		$	5,612
	OREO (2)	5,128				6,858				935				1,463
	Total	$	32,362			$	47,574			$	(718	)		$	7,075
	(1)	Represents the fair value of loans adjusted to the appraised value of the collateral with a write-down in fair value or change in specific reserves during the respective period. These fair value adjustments are recorded against the allowance for loan losses.
	(2)	Represents the fair value of foreclosed properties that were adjusted subsequent to their initial classification as foreclosed assets. Write-downs are recognized as a component of net foreclosed real estate expense in the Consolidated Statements of Income.
Quantitative Information Regarding Level 3 Fair Value Measurements	Quantitative Information Regarding Level 3 Fair Value Measurements
	(Dollars in thousands)
	Financial Instrument:		Fair Value				Valuation Technique(s)		Unobservable		Range		Weighted
			of Assets /						Input				Average
			(Liabilities) at
			31-Mar-15
	Watch list derivatives		$	1,054			Discounted cash flow		Loss factors		4.5% to 16.5%		13.9	%
	Risk participation agreements		$	(6	)	(1)	Discounted cash flow		Loss factors		0.6% to 16.5%		4	%
	Collateral-dependent impaired loans		$	27,234			Sales comparison,		Property specific		-2.0% to -15.9%		-8.1	%	(2)
							income capitalization		adjustment
							and/or cost approach
	OREO		$	5,128			Sales comparison,		Property specific		-2.4% to -18.8%		-14.8	%	(2)
							income capitalization		adjustment
							and/or cost approach
	(1)	Represents fair value of underlying swap.
	(2)	Weighted average is calculated based on assets with a property specific adjustment.
Financial Instruments	Financial Instruments
	(Amounts in thousands)
		As of March 31, 2015
		Carrying Amount								Fair Value Measurements Using
						Fair Value				Level 1				Level 2			Level 3
	Financial Assets:
	Cash and due from banks	$	158,431			$	158,431			$	158,431			$	—		$	—
	Federal funds sold and interest-bearing deposits in banks	799,953				799,953				—				799,953			—
	Loans held-for-sale	89,461				89,461				—				89,461			—
	Securities available-for-sale	1,631,237				1,631,237				244,556				1,386,681			—
	Securities held-to-maturity	1,159,853				1,173,402				—				1,173,402			—
	FHLB stock	28,556				28,556				—				28,556			—
	Loans, net of allowance for loan losses and unearned fees	12,013,874				11,951,864				—				—			11,951,864
	Covered assets, net of allowance for covered loan losses	26,170				32,030				—				—			32,030
	Accrued interest receivable	41,202				41,202				—				—			41,202
	Investment in BOLI	55,561				55,561				—				—			55,561
	Derivative assets	56,607				56,607				—				55,542			1,065
	Financial Liabilities:
	Deposits	$	14,101,728			$	14,110,642			$	—			$	11,591,322		$	2,519,320
	Short-term and secured borrowings	258,788				257,809				—				252,675			5,134
	Long-term debt	344,788				338,520				206,537				54,942			77,041
	Accrued interest payable	7,004				7,004				—				—			7,004
	Derivative liabilities	26,967				26,967				—				26,950			17
	Financial Instruments (Continued)
	(Amounts in thousands)
		As of December 31, 2014
		Carrying Amount								Fair Value Measurements Using
						Fair Value				Level 1				Level 2			Level 3
	Financial Assets:
	Cash and due from banks	$	132,211			$	132,211			$	132,211			$	—		$	—
	Federal funds sold and interest-bearing deposits in banks	292,341				292,341				—				292,341			—
	Loans held-for-sale	115,161				115,161				—				115,161			—
	Securities available-for-sale	1,645,344				1,645,344				268,265				1,377,079			—
	Securities held-to-maturity	1,129,285				1,132,615				—				1,132,615			—
	FHLB stock	28,666				28,666				—				28,666			—
	Loans, net of allowance for loan losses and unearned fees	11,739,721				11,736,461				—				—			11,736,461
	Covered assets, net of allowance for covered loan losses	28,941				33,988				—				—			33,988
	Accrued interest receivable	40,531				40,531				—				—			40,531
	Investment in BOLI	55,207				55,207				—				—			55,207
	Derivative assets	43,062				43,062				—				42,286			776
	Financial Liabilities:
	Deposits	$	13,089,968			$	13,095,657			$	—			$	10,595,040		$	2,500,617
	Deposits held-for-sale	122,216				117,572				—				117,572			—
	Short-term and secured borrowings	432,385				430,944				—				427,150			3,794
	Long-term debt	344,788				332,374				204,320				54,092			73,962
	Accrued interest payable	6,948				6,948				—				—			6,948
	Derivative liabilities	26,767				26,767				—				26,727			40

OPERATING_SEGMENTS_Tables

OPERATING SEGMENTS (Tables)	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Operating Segments Performance	Operating Segments Performance
	(Amounts in thousands)
		Quarter Ended March 31,
		Banking				Asset Management						Holding Company						Consolidated
												and Other
												Adjustments
		2015		2014		2015			2014			2015			2014			2015		2014
	Net interest income (loss)	$	126,498	$	115,152	$	899		$	787		$	(5,404	)	$	(7,187	)	$	121,993	$	108,752
	Provision for loan and covered loan losses	5,646		3,707		—			—			—			—			5,646		3,707
	Non-interest income	29,138		21,872		4,363			4,349			15			15			33,516		26,236
	Non-interest expense	75,935		68,660		4,312			4,076			2,898			3,014			83,145		75,750
	Income (loss) before taxes	74,055		64,657		950			1,060			(8,287		)	(10,186		)	66,718		55,531
	Income tax provision (benefit)	27,937		24,653		374			418			(3,077		)	(4,045		)	25,234		21,026
	Net income (loss)	$	46,118	$	40,004	$	576		$	642		$	(5,210	)	$	(6,141	)	$	41,484	$	34,505
		Banking				Holding Company and Other Adjustments(1)						Consolidated
	Selected Balances	3/31/15		12/31/14		3/31/15			12/31/14			3/31/15			12/31/14
	Assets	$	14,583,189	$	13,882,805	$	1,778,159		$	1,720,577		$	16,361,348		$	15,603,382
	Total loans	12,170,484		11,892,219		—			—			12,170,484			11,892,219
	Deposits, excluding deposits held-for-sale	14,156,257		13,150,600		(54,529		)	(60,632		)	14,101,728			13,089,968
	(1)	Deposit amounts represent the elimination of Holding Company cash accounts included in total deposits of the Banking segment.

VARIABLE_INTEREST_ENTITIES_Tab

VARIABLE INTEREST ENTITIES (Tables)	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Nonconsolidated Variable Interest Entities	Nonconsolidated VIEs
	(Amounts in thousands)
		31-Mar-15				31-Dec-14
		Carrying		Maximum		Carrying		Maximum
		Amount		Exposure		Amount		Exposure
				to Loss				to Loss
	Trust preferred capital securities issuances	$	169,788	$	—	$	169,788	$	—
	Community reinvestment investments	11,431		13,125		14,360		16,054
	Restructured loans to commercial clients (1):
	Outstanding loan balance	50,425		55,886		49,376		57,782
	Related derivative asset	2,961		2,961		6,533		6,533
	Total	$	234,605	$	71,972	$	240,057	$	80,369
	(1)	Excludes personal loans and loans to non-for-profit entities.

Securities_Securities_Portfoli

Securities (Securities Portfolio) (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Investment [Line Items]
Securities Available-for-Sale, Amortized Cost	$1,591,182	$1,613,345
Securities Available-for-Sale, Gross Unrealized Gains	42,171	36,734
Securities Available-for-Sale, Gross Unrealized Losses	-2,116	-4,735
Securities available-for-sale, at fair value	1,631,237	1,645,344
Securities held-to-maturity, at amortized cost	1,159,853	1,129,285
Securities Held-to-Maturity, Gross Unrealized Gains	16,910	10,006
Securities Held-to-Maturity, Gross Unrealized Losses	-3,361	-6,676
Securities Held-to-Maturity, Fair Value	1,173,402	1,132,615
U.S. Treasury Securities [Member]
Investment [Line Items]
Securities Available-for-Sale, Amortized Cost	243,608	269,697
Securities Available-for-Sale, Gross Unrealized Gains	1,186	120
Securities Available-for-Sale, Gross Unrealized Losses	-238	-1,552
Securities available-for-sale, at fair value	244,556	268,265
U.S. Agency [Member]
Investment [Line Items]
Securities Available-for-Sale, Amortized Cost	46,847	46,959
Securities Available-for-Sale, Gross Unrealized Gains	20	0
Securities Available-for-Sale, Gross Unrealized Losses	-61	-701
Securities available-for-sale, at fair value	46,806	46,258
Collateralized mortgage obligations [Member]
Investment [Line Items]
Securities Available-for-Sale, Amortized Cost	123,181	132,633
Securities Available-for-Sale, Gross Unrealized Gains	4,647	4,334
Securities Available-for-Sale, Gross Unrealized Losses	0	-34
Securities available-for-sale, at fair value	127,828	136,933
Securities held-to-maturity, at amortized cost	58,209	59,960
Securities Held-to-Maturity, Gross Unrealized Gains	0	0
Securities Held-to-Maturity, Gross Unrealized Losses	-1,273	-2,017
Securities Held-to-Maturity, Fair Value	56,936	57,943
Residential mortgage-backed securities [Member]
Investment [Line Items]
Securities Available-for-Sale, Amortized Cost	802,921	822,746
Securities Available-for-Sale, Gross Unrealized Gains	27,797	25,058
Securities Available-for-Sale, Gross Unrealized Losses	-1,305	-1,726
Securities available-for-sale, at fair value	829,413	846,078
Securities held-to-maturity, at amortized cost	909,643	885,235
Securities Held-to-Maturity, Gross Unrealized Gains	15,195	9,410
Securities Held-to-Maturity, Gross Unrealized Losses	-1,470	-2,483
Securities Held-to-Maturity, Fair Value	923,368	892,162
Commercial mortgage-backed securities [Member]
Investment [Line Items]
Securities held-to-maturity, at amortized cost	190,932	183,021
Securities Held-to-Maturity, Gross Unrealized Gains	1,710	592
Securities Held-to-Maturity, Gross Unrealized Losses	-618	-2,176
Securities Held-to-Maturity, Fair Value	192,024	181,437
State and municipal securities [Member]
Investment [Line Items]
Securities Available-for-Sale, Amortized Cost	374,125	340,810
Securities Available-for-Sale, Gross Unrealized Gains	8,521	7,222
Securities Available-for-Sale, Gross Unrealized Losses	-512	-722
Securities available-for-sale, at fair value	382,134	347,310
Securities held-to-maturity, at amortized cost	1,069	1,069
Securities Held-to-Maturity, Gross Unrealized Gains	5	4
Securities Held-to-Maturity, Gross Unrealized Losses	0	0
Securities Held-to-Maturity, Fair Value	1,074	1,073
Foreign sovereign debt [Member]
Investment [Line Items]
Securities Available-for-Sale, Amortized Cost	500	500
Securities Available-for-Sale, Gross Unrealized Gains	0	0
Securities Available-for-Sale, Gross Unrealized Losses	0	0
Securities available-for-sale, at fair value	$500	$500

Securities_Narrative_Detail

Securities (Narrative) (Detail) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Disclosure Securities Narrative [Abstract]
Available-for-sale and held-to-maturity securities, pledged, carrying value	$383,500,000	$353,100,000
Securities pledged as collateral which may be sold or re-pledged by the secured party	86,100,000	86,500,000
Investments securities from one issuer that exceeds maximum percentage	0	0
Percentage of securities portfolio from one issuer, maximum	10.00%	10.00%
Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value, Total	315,200,000	616,800,000
Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses	4,200,000	10,900,000
Other than Temporary Impairment Losses, Investments	$0	$0

Securities_Securities_In_Unrea

Securities (Securities In Unrealized Loss Position) (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Investment [Line Items]
Securities Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	$106,109	$176,890
Securities Available-for-Sale, Continuous Unrealized Loss Position, Less Than 12 Months, Unrealized Losses	-554	-442
Securities Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	143,237	290,612
Securities Available-for-Sale, Continuous Unrealized Loss Position, 12 Months Or Longer, Unrealized Losses	-1,562	-4,293
Securities Available-for-Sale, Continuous Unrealized Loss Position, Total Fair Value	249,346	467,502
Securities Available-for-Sale, Continuous Unrealized Loss Position, Total Unrealized Losses	-2,116	-4,735
Securities Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	142,277	55,888
Securities Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	-767	-66
Securities Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	171,942	326,216
Securities Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses	-2,594	-6,610
Securities Held-to-Maturity, Continuous Unrealized Loss Position, Total Fair Value	314,219	382,104
Securities Held-to-Maturity, Continuous Unrealized Loss Position, Total Unrealized Losses	-3,361	-6,676
U.S. Treasury Securities [Member]
Investment [Line Items]
Securities Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	25,187	119,233
Securities Available-for-Sale, Continuous Unrealized Loss Position, Less Than 12 Months, Unrealized Losses	-46	-159
Securities Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	52,348	123,117
Securities Available-for-Sale, Continuous Unrealized Loss Position, 12 Months Or Longer, Unrealized Losses	-192	-1,393
Securities Available-for-Sale, Continuous Unrealized Loss Position, Total Fair Value	77,535	242,350
Securities Available-for-Sale, Continuous Unrealized Loss Position, Total Unrealized Losses	-238	-1,552
U.S. Agency [Member]
Investment [Line Items]
Securities Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	14,875	0
Securities Available-for-Sale, Continuous Unrealized Loss Position, Less Than 12 Months, Unrealized Losses	-61	0
Securities Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	0	46,258
Securities Available-for-Sale, Continuous Unrealized Loss Position, 12 Months Or Longer, Unrealized Losses	0	-701
Securities Available-for-Sale, Continuous Unrealized Loss Position, Total Fair Value	14,875	46,258
Securities Available-for-Sale, Continuous Unrealized Loss Position, Total Unrealized Losses	-61	-701
Collateralized mortgage obligations [Member]
Investment [Line Items]
Securities Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value		4,565
Securities Available-for-Sale, Continuous Unrealized Loss Position, Less Than 12 Months, Unrealized Losses		-34
Securities Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value		0
Securities Available-for-Sale, Continuous Unrealized Loss Position, 12 Months Or Longer, Unrealized Losses		0
Securities Available-for-Sale, Continuous Unrealized Loss Position, Total Fair Value		4,565
Securities Available-for-Sale, Continuous Unrealized Loss Position, Total Unrealized Losses		-34
Securities Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	0	0
Securities Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	0	0
Securities Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	56,936	57,943
Securities Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses	-1,273	-2,017
Securities Held-to-Maturity, Continuous Unrealized Loss Position, Total Fair Value	56,936	57,943
Securities Held-to-Maturity, Continuous Unrealized Loss Position, Total Unrealized Losses	-1,273	-2,017
Residential mortgage-backed securities [Member]
Investment [Line Items]
Securities Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	2,577	0
Securities Available-for-Sale, Continuous Unrealized Loss Position, Less Than 12 Months, Unrealized Losses	-6	0
Securities Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	86,266	89,085
Securities Available-for-Sale, Continuous Unrealized Loss Position, 12 Months Or Longer, Unrealized Losses	-1,299	-1,726
Securities Available-for-Sale, Continuous Unrealized Loss Position, Total Fair Value	88,843	89,085
Securities Available-for-Sale, Continuous Unrealized Loss Position, Total Unrealized Losses	-1,305	-1,726
Securities Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	118,201	45,867
Securities Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	-643	-38
Securities Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	64,950	162,564
Securities Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses	-827	-2,445
Securities Held-to-Maturity, Continuous Unrealized Loss Position, Total Fair Value	183,151	208,431
Securities Held-to-Maturity, Continuous Unrealized Loss Position, Total Unrealized Losses	-1,470	-2,483
Commercial mortgage-backed securities [Member]
Investment [Line Items]
Securities Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	24,076	10,021
Securities Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	-124	-28
Securities Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	50,056	105,709
Securities Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses	-494	-2,148
Securities Held-to-Maturity, Continuous Unrealized Loss Position, Total Fair Value	74,132	115,730
Securities Held-to-Maturity, Continuous Unrealized Loss Position, Total Unrealized Losses	-618	-2,176
State and municipal securities [Member]
Investment [Line Items]
Securities Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	63,470	53,092
Securities Available-for-Sale, Continuous Unrealized Loss Position, Less Than 12 Months, Unrealized Losses	-441	-249
Securities Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	4,623	32,152
Securities Available-for-Sale, Continuous Unrealized Loss Position, 12 Months Or Longer, Unrealized Losses	-71	-473
Securities Available-for-Sale, Continuous Unrealized Loss Position, Total Fair Value	68,093	85,244
Securities Available-for-Sale, Continuous Unrealized Loss Position, Total Unrealized Losses	($512)	($722)

Securities_Remaining_Contractu

Securities (Remaining Contractual Maturity Of Securities) (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Investment [Line Items]
Available-For-Sale Securities, Amortized Cost	$1,591,182	$1,613,345
Securities available-for-sale, at fair value	1,631,237	1,645,344
Securities held-to-maturity, at amortized cost	1,159,853	1,129,285
Securities Held-to-Maturity, Fair Value	1,173,402	1,132,615
U.S. Treasury, U.S. Agency, state and municipal and foreign sovereign debt securities [Member]
Investment [Line Items]
Available-For-Sale Securities, One year or less, Amortized Cost	7,839
Available-For-Sale Securities, One year to five years, Amortized Cost	447,192
Available-For-Sale Securities, Five years to ten years, Amortized Cost	195,714
Available-For-Sale Securities, After ten years, Amortized Cost	14,335
Available-For-Sale Securities, One year or less, Fair Value	7,985
Available-For-Sale Securities, One year to five years, Fair Value	452,133
Available-For-Sale Securities, Five years to ten years, Fair Value	199,318
Available-For-Sale Securities, After ten years, Fair value	14,560
Held-to-Maturity Securities, One year or less, Amortized Cost	816
Held-to-Maturity Securities, One year to five years, Amortized Cost	253
Held-to-Maturity Securities, Five years to ten years, Amortized Cost	0
Held-to-Maturity Securities, After ten years, Amortized Cost	0
Held-to-Maturity Securities, Debt Maturities, One year or less, Fair Value	817
Held-to-Maturity Securities, Debt Maturities, One year to five years, Fair Value	257
Held-to-Maturity Securities, Debt Maturities, Five years to ten years, Fair Value	0
Held-to-Maturity Securities, Debt Maturities, After ten years, Fair Value	0
Collateralized mortgage obligations [Member]
Investment [Line Items]
Available-For-Sale Securities, All other securities, Without Single Maturity Date, Amortized Cost	123,181
Available-For-Sale Securities, Amortized Cost	123,181	132,633
Available-For-Sale Securities, All other securities, Without Single Maturity Date, Fair Value	127,828
Securities available-for-sale, at fair value	127,828	136,933
Held-to-Maturity Securities, All other securities, Without Single Maturity Date, Amortized Cost	58,209
Securities held-to-maturity, at amortized cost	58,209	59,960
Held-to-Maturity Securities, All other securities, Without Single Maturity Date, Fair Value	56,936
Securities Held-to-Maturity, Fair Value	56,936	57,943
Residential mortgage-backed securities [Member]
Investment [Line Items]
Available-For-Sale Securities, All other securities, Without Single Maturity Date, Amortized Cost	802,921
Available-For-Sale Securities, Amortized Cost	802,921	822,746
Available-For-Sale Securities, All other securities, Without Single Maturity Date, Fair Value	829,413
Securities available-for-sale, at fair value	829,413	846,078
Held-to-Maturity Securities, All other securities, Without Single Maturity Date, Amortized Cost	909,643
Securities held-to-maturity, at amortized cost	909,643	885,235
Held-to-Maturity Securities, All other securities, Without Single Maturity Date, Fair Value	923,368
Securities Held-to-Maturity, Fair Value	923,368	892,162
Commercial mortgage-backed securities [Member]
Investment [Line Items]
Available-For-Sale Securities, All other securities, Without Single Maturity Date, Amortized Cost	0
Available-For-Sale Securities, All other securities, Without Single Maturity Date, Fair Value	0
Held-to-Maturity Securities, All other securities, Without Single Maturity Date, Amortized Cost	190,932
Securities held-to-maturity, at amortized cost	190,932	183,021
Held-to-Maturity Securities, All other securities, Without Single Maturity Date, Fair Value	192,024
Securities Held-to-Maturity, Fair Value	$192,024	$181,437

Securities_Securities_Gains_Lo

Securities (Securities Gains (Losses)) (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Gain (Loss) on Investments [Line Items]
Proceeds from sales	$28,931	$47,477
Gross realized gains	538	397
Gross realized losses	-4	-66
Net realized gains (losses)	534	331
Income tax provision (benefit) on net realized gains (losses)	$210	$131

Loans_and_Credit_Quality_Loan_

Loans and Credit Quality (Loan Portfolio) (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Loans [Line Items]
Commercial and industrial	$6,213,029	$5,996,070
Commercial - owner-occupied CRE	1,977,601	1,892,564
Total commercial	8,190,630	7,888,634
Commercial real estate	2,411,359	2,323,616
Commercial real estate - multi-family	492,695	593,103
Total Commercial real estate	2,904,054	2,916,719
Construction	357,258	381,102
Residential real estate	376,741	361,565
Home equity	138,734	142,177
Personal	203,067	202,022
Total loans	12,170,484	11,892,219	10,924,985
Net deferred loan fees and unamortized discount and premium on loans, included as a reduction in total loans	46,862	47,017
Overdrawn demand deposits included in total loans	$1,540	$1,963

LOANS_AND_CREDIT_QUALITY_Loans

LOANS AND CREDIT QUALITY Loans and Credit Quality (Loans Held-For-Sale) (Details) (USD $)	Mar. 31, 2015		Dec. 31, 2014
In Thousands, unless otherwise specified
Loans Held-for-Sale [Abstract]
Mortgage loans held-for-sale	$21,866	[1]	$42,215	[1]
Other loans held-for-sale	67,595	[2]	72,946	[2]
Total loans held-for-sale	$89,461		$115,161
[1]	Comprised of residential mortgage loan originations intended to be sold in the secondary market. The Company accounts for these loans under the fair value option. Refer to Note 16 for additional information regarding mortgage loans held-for-sale.
[2]	Amounts at March 31, 2015 represent commercial, commercial real estate, and construction loans carried at the lower of aggregate cost or fair value. Generally, the Company intends to sell these loans within 30-60 days from the date the intent to sell was established. Amounts at December 31, 2014 consists of $36.6 million of commercial, commercial real estate and construction loans carried at the lower of aggregate cost or fair value and $36.3 million of commercial, commercial real estate, construction, home equity and personal loans held-for-sale in connection with the sale of the Company's banking office located in Norcross, Georgia, which closed in January 2015.

Loans_and_Credit_Quality_Carry

Loans and Credit Quality (Carrying Value Of Loans Pledged) (Detail) (USD $)	Mar. 31, 2015		Dec. 31, 2014
In Thousands, unless otherwise specified
Loans pledged to secure outstanding borrowings or availability: [Abstract]
Loans pledged to secure FRB discount window borrowings	$458,615	[1]	$478,692	[1]
Loans pledged to secure FHLB advances	1,851,727	[2]	1,576,168	[2]
Total	$2,310,342		$2,054,860
[1]	No borrowings were outstanding at March 31, 2015 or December 31, 2014.
[2]	Refer to Notes 7 and 8 for additional information regarding FHLB advances.

Loans_and_Credit_Quality_Loan_1

Loans and Credit Quality (Loan Portfolio Aging) (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Loans [Line Items]
Loan Portfolio Aging, Current	$12,090,249	$11,812,859
Loan Portfolio Aging, 30 - 59 Days Past Due	6,673	7,696
Loan Portfolio Aging, 60 - 89 Days Past Due	2,544	4,120
Loan Portfolio Aging, 90 Days Past Due and Accruing	0	0
Loan Portfolio Aging, Total Accruing Loans	12,099,466	11,824,675
Loan Portfolio Aging, Nonaccrual	71,018	67,544
Total Commercial	8,190,630	7,888,634
Total Commercial real estate	2,904,054	2,916,719
Total Construction	357,258	381,102
Total Residential real estate	376,741	361,565
Total Home equity	138,734	142,177
Total Personal	203,067	202,022
Total loans	12,170,484	11,892,219	10,924,985
Commercial [Member]
Loans [Line Items]
Loan Portfolio Aging, Current	8,147,503	7,855,833
Loan Portfolio Aging, 30 - 59 Days Past Due	1,862	762
Loan Portfolio Aging, 60 - 89 Days Past Due	2,292	992
Loan Portfolio Aging, 90 Days Past Due and Accruing	0	0
Loan Portfolio Aging, Total Accruing Loans	8,151,657	7,857,587
Loan Portfolio Aging, Nonaccrual	38,973	31,047
Total loans	8,190,630		7,396,948
Commercial real estate [Member]
Loans [Line Items]
Loan Portfolio Aging, Current	2,888,347	2,891,301
Loan Portfolio Aging, 30 - 59 Days Past Due	88	5,408
Loan Portfolio Aging, 60 - 89 Days Past Due	0	261
Loan Portfolio Aging, 90 Days Past Due and Accruing	0	0
Loan Portfolio Aging, Total Accruing Loans	2,888,435	2,896,970
Loan Portfolio Aging, Nonaccrual	15,619	19,749
Total loans	2,904,054		2,499,406
Construction [Member]
Loans [Line Items]
Loan Portfolio Aging, Current	356,308	380,939
Loan Portfolio Aging, 30 - 59 Days Past Due	950	163
Loan Portfolio Aging, 60 - 89 Days Past Due	0	0
Loan Portfolio Aging, 90 Days Past Due and Accruing	0	0
Loan Portfolio Aging, Total Accruing Loans	357,258	381,102
Loan Portfolio Aging, Nonaccrual	0	0
Total loans	357,258		335,476
Residential real estate [Member]
Loans [Line Items]
Loan Portfolio Aging, Current	368,824	354,717
Loan Portfolio Aging, 30 - 59 Days Past Due	2,912	943
Loan Portfolio Aging, 60 - 89 Days Past Due	242	631
Loan Portfolio Aging, 90 Days Past Due and Accruing	0	0
Loan Portfolio Aging, Total Accruing Loans	371,978	356,291
Loan Portfolio Aging, Nonaccrual	4,763	5,274
Total loans	376,741		337,832
Home equity [Member]
Loans [Line Items]
Loan Portfolio Aging, Current	126,575	128,500
Loan Portfolio Aging, 30 - 59 Days Past Due	814	397
Loan Portfolio Aging, 60 - 89 Days Past Due	0	2,236
Loan Portfolio Aging, 90 Days Past Due and Accruing	0	0
Loan Portfolio Aging, Total Accruing Loans	127,389	131,133
Loan Portfolio Aging, Nonaccrual	11,345	11,044
Total loans	138,734		147,574
Personal [Member]
Loans [Line Items]
Loan Portfolio Aging, Current	202,692	201,569
Loan Portfolio Aging, 30 - 59 Days Past Due	47	23
Loan Portfolio Aging, 60 - 89 Days Past Due	10	0
Loan Portfolio Aging, 90 Days Past Due and Accruing	0	0
Loan Portfolio Aging, Total Accruing Loans	202,749	201,592
Loan Portfolio Aging, Nonaccrual	318	430
Total loans	$203,067		$207,749

Loans_and_Credit_Quality_Impai

Loans and Credit Quality (Impaired Loans) (Detail) (USD $)	Mar. 31, 2015		Dec. 31, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	$111,973		$106,095
Recorded Investment With No Specific Reserve	41,253		39,470
Recorded Investment With Specific Reserve	52,133		50,819
Total Recorded Investment	93,386	[1]	90,289	120,289	[1]
Specific Reserve	15,636	[1]	16,627	22,767	[1]
Commercial [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	70,501		60,174
Recorded Investment With No Specific Reserve	31,582		25,739
Recorded Investment With Specific Reserve	28,166		26,432
Total Recorded Investment	59,748	[1]	52,171	54,700	[1]
Specific Reserve	10,643	[1]	11,487	8,678	[1]
Commercial real estate [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	22,385		26,738
Recorded Investment With No Specific Reserve	6,020		9,755
Recorded Investment With Specific Reserve	9,776		10,193
Total Recorded Investment	15,796	[1]	19,948	42,180	[1]
Specific Reserve	2,201	[1]	2,441	9,479	[1]
Construction [Member]
Financing Receivable, Impaired [Line Items]
Total Recorded Investment	0	[1]		0	[1]
Specific Reserve	0	[1]		0	[1]
Residential real estate [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	5,344		5,849
Recorded Investment With No Specific Reserve	0		349
Recorded Investment With Specific Reserve	4,763		4,925
Total Recorded Investment	4,763	[1]	5,274	9,354	[1]
Specific Reserve	430	[1]	735	2,198	[1]
Home equity [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	13,425		12,904
Recorded Investment With No Specific Reserve	3,651		3,627
Recorded Investment With Specific Reserve	9,110		8,839
Total Recorded Investment	12,761	[1]	12,466	13,430	[1]
Specific Reserve	2,292	[1]	1,855	2,274	[1]
Personal [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	318		430
Recorded Investment With No Specific Reserve	0		0
Recorded Investment With Specific Reserve	318		430
Total Recorded Investment	318	[1]	430	625	[1]
Specific Reserve	$70	[1]	$109	$138	[1]
[1]	Refer to Note 4 for additional information regarding impaired loans.

Loans_and_Credit_Quality_Avera

Loans and Credit Quality (Average Recorded Investment And Interest Income Recognized On Impaired Loans) (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	$89,612	[1]	$114,214	[1]
Interest Income Recognized	209	[1]	430	[1]
Commercial [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	53,048	[1]	43,777	[1]
Interest Income Recognized	184	[1]	382	[1]
Commercial real estate [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	17,897	[1]	46,415	[1]
Interest Income Recognized	3	[1]	24	[1]
Residential real estate [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	4,979	[1]	9,833	[1]
Interest Income Recognized	0	[1]	0	[1]
Home equity [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	13,332	[1]	13,526	[1]
Interest Income Recognized	22	[1]	24	[1]
Personal [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	356	[1]	663	[1]
Interest Income Recognized	$0	[1]	$0	[1]
[1]	Represents amounts while classified as impaired for the periods presented.

Loans_and_Credit_Quality_Narra

Loans and Credit Quality (Narrative) (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014	Dec. 31, 2014
Loans [Line Items]
Loans Held-for-sale, Other	$67,595,000	[1]		$72,946,000	[1]
Loans and leases receivable, impaired, commitment to lend	5,500,000			8,500,000
Specific reserves on nonaccrual troubled debt restructurings	9,900,000			10,600,000
Specific reserves on accruing troubled debt restructurings	0			0
Recorded Investment	0
OREO Recorded Investment of Consumer Mortgage Loans Secured by Residential Real Estate Properties For Which Foreclosure Proceedings Are In Process	4,800,000			5,500,000
Covered assets, net of allowance for covered loan losses	26,170,000			28,941,000
Covered Assets Recorded Investment of Properties For Which Foreclosure Proceedings Are In Process	635,000			856,000
Branch Closing, Sale [Member]
Loans [Line Items]
Loans Held-for-sale, Other				36,300,000
Participating Mortgages [Member]
Loans [Line Items]
Loans Held-for-sale, Other	67,600,000			36,600,000
Commercial real estate [Member]
Loans [Line Items]
Recorded Investment			$699,000
Pass [Member] | Minimum [Member]
Loans [Line Items]
Loans receivable risk rating	1
Loan Rated Five [Member] | Maximum [Member]
Loans [Line Items]
Loans receivable risk rating	5
Special Mention [Member]
Loans [Line Items]
Loans receivable risk rating	6
Potential Problem and Non-Performing [Member]
Loans [Line Items]
Loans receivable risk rating	7
Non-Performing Loans [Member] | Maximum [Member]
Loans [Line Items]
Loans receivable risk rating	8
[1]	Amounts at March 31, 2015 represent commercial, commercial real estate, and construction loans carried at the lower of aggregate cost or fair value. Generally, the Company intends to sell these loans within 30-60 days from the date the intent to sell was established. Amounts at December 31, 2014 consists of $36.6 million of commercial, commercial real estate and construction loans carried at the lower of aggregate cost or fair value and $36.3 million of commercial, commercial real estate, construction, home equity and personal loans held-for-sale in connection with the sale of the Company's banking office located in Norcross, Georgia, which closed in January 2015.

Loans_and_Credit_Quality_Credi

Loans and Credit Quality (Credit Quality Indicators) (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Loans [Line Items]
Special Mention	$102,651	$100,989
Percentage of Special Mention to Portfolio Loan Type	0.80%	0.80%
Potential Problem Loans	107,038	87,442
Percentage of Potential Problem Loans to Portfolio Loan Type	0.90%	0.70%
Non-Performing Loans	71,018	67,544
Percentage of Non-Performing Loans to Portfolio Loan Type	0.60%	0.60%
Total Commercial	8,190,630	7,888,634
Total Commercial real estate	2,904,054	2,916,719
Total Construction	357,258	381,102
Total Residential real estate	376,741	361,565
Total Home equity	138,734	142,177
Total Personal	203,067	202,022
Total loans	12,170,484	11,892,219	10,924,985
Commercial [Member]
Loans [Line Items]
Special Mention	97,851	93,130
Percentage of Special Mention to Portfolio Loan Type	1.20%	1.20%
Potential Problem Loans	95,448	78,562
Percentage of Potential Problem Loans to Portfolio Loan Type	1.20%	1.00%
Non-Performing Loans	38,973	31,047
Percentage of Non-Performing Loans to Portfolio Loan Type	0.50%	0.40%
Total loans	8,190,630		7,396,948
Commercial real estate [Member]
Loans [Line Items]
Special Mention	130	3,552
Percentage of Special Mention to Portfolio Loan Type		0.10%
Potential Problem Loans	2,925	746
Percentage of Potential Problem Loans to Portfolio Loan Type	0.10%
Non-Performing Loans	15,619	19,749
Percentage of Non-Performing Loans to Portfolio Loan Type	0.50%	0.70%
Total loans	2,904,054		2,499,406
Construction [Member]
Loans [Line Items]
Special Mention	0	0
Percentage of Special Mention to Portfolio Loan Type	0.00%	0.00%
Potential Problem Loans	0	0
Percentage of Potential Problem Loans to Portfolio Loan Type	0.00%	0.00%
Non-Performing Loans	0	0
Percentage of Non-Performing Loans to Portfolio Loan Type	0.00%	0.00%
Total loans	357,258		335,476
Residential real estate [Member]
Loans [Line Items]
Special Mention	3,323	2,964
Percentage of Special Mention to Portfolio Loan Type	0.90%	0.80%
Potential Problem Loans	6,045	5,981
Percentage of Potential Problem Loans to Portfolio Loan Type	1.60%	1.70%
Non-Performing Loans	4,763	5,274
Percentage of Non-Performing Loans to Portfolio Loan Type	1.30%	1.50%
Total loans	376,741		337,832
Home equity [Member]
Loans [Line Items]
Special Mention	502	1,170
Percentage of Special Mention to Portfolio Loan Type	0.40%	0.80%
Potential Problem Loans	2,599	2,108
Percentage of Potential Problem Loans to Portfolio Loan Type	1.90%	1.50%
Non-Performing Loans	11,345	11,044
Percentage of Non-Performing Loans to Portfolio Loan Type	8.20%	7.80%
Total loans	138,734		147,574
Personal [Member]
Loans [Line Items]
Special Mention	845	173
Percentage of Special Mention to Portfolio Loan Type	0.40%	0.10%
Potential Problem Loans	21	45
Non-Performing Loans	318	430
Percentage of Non-Performing Loans to Portfolio Loan Type	0.20%	0.20%
Total loans	$203,067		$207,749

Loans_and_Credit_Quality_Troub

Loans and Credit Quality (Troubled Debt Restructured Loans Outstanding) (Detail) (USD $)	Mar. 31, 2015		Dec. 31, 2014
In Thousands, unless otherwise specified
Accruing [Member]
Troubled Debt Restructured Loans Outstanding [Line Items]
Troubled debt restructured loans outstanding	$22,368		$22,745
Accruing [Member] | Commercial [Member]
Troubled Debt Restructured Loans Outstanding [Line Items]
Troubled debt restructured loans outstanding	20,775		21,124
Accruing [Member] | Commercial real estate [Member]
Troubled Debt Restructured Loans Outstanding [Line Items]
Troubled debt restructured loans outstanding	177		199
Accruing [Member] | Residential real estate [Member]
Troubled Debt Restructured Loans Outstanding [Line Items]
Troubled debt restructured loans outstanding	0		0
Accruing [Member] | Home equity [Member]
Troubled Debt Restructured Loans Outstanding [Line Items]
Troubled debt restructured loans outstanding	1,416		1,422
Accruing [Member] | Personal [Member]
Troubled Debt Restructured Loans Outstanding [Line Items]
Troubled debt restructured loans outstanding	0		0
Nonaccrual [Member]
Troubled Debt Restructured Loans Outstanding [Line Items]
Troubled debt restructured loans outstanding	37,390	[1]	36,298	[1]
Nonaccrual [Member] | Commercial [Member]
Troubled Debt Restructured Loans Outstanding [Line Items]
Troubled debt restructured loans outstanding	17,333	[1]	20,113	[1]
Nonaccrual [Member] | Commercial real estate [Member]
Troubled Debt Restructured Loans Outstanding [Line Items]
Troubled debt restructured loans outstanding	12,335	[1]	8,005	[1]
Nonaccrual [Member] | Residential real estate [Member]
Troubled Debt Restructured Loans Outstanding [Line Items]
Troubled debt restructured loans outstanding	1,737	[1]	1,881	[1]
Nonaccrual [Member] | Home equity [Member]
Troubled Debt Restructured Loans Outstanding [Line Items]
Troubled debt restructured loans outstanding	5,701	[1]	5,886	[1]
Nonaccrual [Member] | Personal [Member]
Troubled Debt Restructured Loans Outstanding [Line Items]
Troubled debt restructured loans outstanding	$284	[1]	$413	[1]
[1]	Included in nonperforming loans.

Loans_and_Credit_Quality_Addit

Loans and Credit Quality (Additions To TDR During The Period) (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
	borrower		borrower
Accruing Interest [Member]
Financing Receivable, Modifications [Line Items]
Number of Borrowers	1		3
Recorded Investment, Pre-Modification	$2,394	[1]	$13,567	[1]
Recorded Investment, Post-Modification	2,394	[1]	13,567	[1]
Accruing Interest [Member] | Commercial [Member]
Financing Receivable, Modifications [Line Items]
Number of Borrowers	1		2
Recorded Investment, Pre-Modification	2,394	[1]	13,141	[1]
Recorded Investment, Post-Modification	2,394	[1]	13,141	[1]
Accruing Interest [Member] | Commercial [Member] | Extension of maturity date [Member]
Financing Receivable, Modifications [Line Items]
Number of Borrowers	1		1
Recorded Investment, Pre-Modification	2,394	[1],[2]	200	[1],[2]
Recorded Investment, Post-Modification	2,394	[1],[2]	200	[1],[2]
Accruing Interest [Member] | Commercial [Member] | Other concession [Member]
Financing Receivable, Modifications [Line Items]
Number of Borrowers	0		1
Recorded Investment, Pre-Modification	0	[1],[3]	12,941	[1],[3]
Recorded Investment, Post-Modification	0	[1],[3]	12,941	[1],[3]
Accruing Interest [Member] | Commercial real estate [Member] | Other concession [Member]
Financing Receivable, Modifications [Line Items]
Number of Borrowers	0		1
Recorded Investment, Pre-Modification	0	[1],[3]	426	[1],[3]
Recorded Investment, Post-Modification	0	[1],[3]	426	[1],[3]
Non Accrual [Member]
Financing Receivable, Modifications [Line Items]
Number of Borrowers	6		6
Recorded Investment, Pre-Modification	6,270	[1]	1,315	[1]
Recorded Investment, Post-Modification	6,176	[1]	1,265	[1],[3]
Change in recorded investment due to principal paydown (advances) at time of modification	94	[1]	50	[1]
Non Accrual [Member] | Commercial [Member] | Other concession [Member]
Financing Receivable, Modifications [Line Items]
Number of Borrowers	1		2
Recorded Investment, Pre-Modification	673	[1],[3]	456	[1],[3]
Recorded Investment, Post-Modification	666	[1],[3]	406	[1],[3]
Non Accrual [Member] | Commercial real estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Borrowers	3		0
Recorded Investment, Pre-Modification	5,520	[1]	0	[1]
Recorded Investment, Post-Modification	5,433	[1]	0	[1]
Non Accrual [Member] | Commercial real estate [Member] | Extension of maturity date [Member]
Financing Receivable, Modifications [Line Items]
Number of Borrowers	2		0
Recorded Investment, Pre-Modification	1,747	[1],[2]	0	[1],[2]
Recorded Investment, Post-Modification	1,660	[1],[2]	0	[1],[2]
Non Accrual [Member] | Commercial real estate [Member] | Other concession [Member]
Financing Receivable, Modifications [Line Items]
Number of Borrowers	1		0
Recorded Investment, Pre-Modification	3,773	[1],[3]	0	[1],[3]
Recorded Investment, Post-Modification	3,773	[1],[3]	0	[1],[3]
Non Accrual [Member] | Residential real estate [Member] | Other concession [Member]
Financing Receivable, Modifications [Line Items]
Number of Borrowers	0		2
Recorded Investment, Pre-Modification	0	[1],[3]	495	[1],[3]
Recorded Investment, Post-Modification	0	[1],[3]	495	[1],[3]
Non Accrual [Member] | Home equity [Member]
Financing Receivable, Modifications [Line Items]
Number of Borrowers	2		2
Recorded Investment, Pre-Modification	77	[1]	364	[1]
Recorded Investment, Post-Modification	77	[1]	364	[1]
Non Accrual [Member] | Home equity [Member] | Extension of maturity date [Member]
Financing Receivable, Modifications [Line Items]
Number of Borrowers	0		1
Recorded Investment, Pre-Modification	0	[1],[2]	114	[1],[2]
Recorded Investment, Post-Modification	0	[1],[2]	114	[1],[2]
Non Accrual [Member] | Home equity [Member] | Other concession [Member]
Financing Receivable, Modifications [Line Items]
Number of Borrowers	2		1
Recorded Investment, Pre-Modification	77	[1],[3]	250	[1],[3]
Recorded Investment, Post-Modification	$77	[1],[3]	$250	[1],[3]
[1]	Represents amounts as of the date immediately prior to and immediately after the modification is effective.
[2]	Extension of maturity date also includes loans renewed at existing rate of interest which is considered a below market rate for that particular loan’s risk profile.
[3]	Other concessions primarily include interest rate reductions, loan increases or deferrals of principal.

LOANS_AND_CREDIT_QUALITY_Loans1

LOANS AND CREDIT QUALITY Loans and Credit Quality (OREO Composition) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
OREO [Line Items]
Other real estate owned (OREO)	$15,625	$17,416
Single-Family Homes [Member]
OREO [Line Items]
Other real estate owned (OREO)	7,698	7,902
Land Parcels [Member]
OREO [Line Items]
Other real estate owned (OREO)	3,971	4,237
Multi-Family [Member]
OREO [Line Items]
Other real estate owned (OREO)	465	488
Office/Industrial [Member]
OREO [Line Items]
Other real estate owned (OREO)	2,663	3,832
Retail [Member]
OREO [Line Items]
Other real estate owned (OREO)	$828	$957

LOANS_AND_CREDIT_QUALITY_Loans2

LOANS AND CREDIT QUALITY Loans and Credit Quality (Covered Assets) (Details) (USD $)	Mar. 31, 2015		Dec. 31, 2014
Disclosure Covered Assets Carrying Amount Of Covered Assets [Abstract]
Residential mortgage loans	$29,963,000	[1]	$32,182,000	[1]
Foreclosed real estate - single family homes	203,000		187,000
Estimated loss reimbursement by the FDIC	2,025,000		1,763,000
Covered assets	32,191,000		34,132,000
Allowance for covered loan losses	-6,021,000		-5,191,000
Covered assets, net of allowance for covered loan losses	26,170,000		28,941,000
Purchased Impaired Loans Carrying Amount	$266,000		$420,000
[1]	Includes $266,000 and $420,000 of purchased impaired loans as of March 31, 2015 and December 31, 2014, respectively.

Recovered_Sheet1

Allowance For Loan Losses And Reserve For Unfunded Commitments (Allowance For Loan Losses and Recorded Investment in Loans) (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014		Dec. 31, 2014
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	$152,498		$143,109
Loans charged-off	-3,507		-4,881
Recoveries on loans previously charged-off	2,128		5,091
Net recoveries (charge-offs)	-1,379		210
Provision (release) for loan losses	5,491		3,449
Balance at end of period	156,610		146,768
Ending balance, loans individually evaluated for impairment	15,636	[1]	22,767	[1]	16,627
Ending balance, loans collectively evaluated for impairment	140,974		124,001
Recorded Investment in Loans, Ending balance, loans individually evaluated for impairment	93,386	[1]	120,289	[1]	90,289
Recorded Investment in Loans, Ending balance, loans collectively evaluated for impairment	12,077,098		10,804,696
Total loans	12,170,484		10,924,985		11,892,219
Commercial [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	103,462		80,768
Loans charged-off	-2,202		-1,487
Recoveries on loans previously charged-off	511		3,662
Net recoveries (charge-offs)	-1,691		2,175
Provision (release) for loan losses	7,102		7,137
Balance at end of period	108,873		90,080
Ending balance, loans individually evaluated for impairment	10,643	[1]	8,678	[1]	11,487
Ending balance, loans collectively evaluated for impairment	98,230		81,402
Recorded Investment in Loans, Ending balance, loans individually evaluated for impairment	59,748	[1]	54,700	[1]	52,171
Recorded Investment in Loans, Ending balance, loans collectively evaluated for impairment	8,130,882		7,342,248
Total loans	8,190,630		7,396,948
Commercial real estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	31,838		42,362
Loans charged-off	-887		-2,582
Recoveries on loans previously charged-off	598		688
Net recoveries (charge-offs)	-289		-1,894
Provision (release) for loan losses	57		-2,893
Balance at end of period	31,606		37,575
Ending balance, loans individually evaluated for impairment	2,201	[1]	9,479	[1]	2,441
Ending balance, loans collectively evaluated for impairment	29,405		28,096
Recorded Investment in Loans, Ending balance, loans individually evaluated for impairment	15,796	[1]	42,180	[1]	19,948
Recorded Investment in Loans, Ending balance, loans collectively evaluated for impairment	2,888,258		2,457,226
Total loans	2,904,054		2,499,406
Construction [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	4,290		3,338
Loans charged-off	0		0
Recoveries on loans previously charged-off	19		7
Net recoveries (charge-offs)	19		7
Provision (release) for loan losses	-283		202
Balance at end of period	4,026		3,547
Ending balance, loans individually evaluated for impairment	0	[1]	0	[1]
Ending balance, loans collectively evaluated for impairment	4,026		3,547
Recorded Investment in Loans, Ending balance, loans individually evaluated for impairment	0	[1]	0	[1]
Recorded Investment in Loans, Ending balance, loans collectively evaluated for impairment	357,258		335,476
Total loans	357,258		335,476
Residential real estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	5,316		7,555
Loans charged-off	-37		-235
Recoveries on loans previously charged-off	57		300
Net recoveries (charge-offs)	20		65
Provision (release) for loan losses	-113		-642
Balance at end of period	5,223		6,978
Ending balance, loans individually evaluated for impairment	430	[1]	2,198	[1]	735
Ending balance, loans collectively evaluated for impairment	4,793		4,780
Recorded Investment in Loans, Ending balance, loans individually evaluated for impairment	4,763	[1]	9,354	[1]	5,274
Recorded Investment in Loans, Ending balance, loans collectively evaluated for impairment	371,978		328,478
Total loans	376,741		337,832
Home equity [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	4,924		5,648
Loans charged-off	-371		-447
Recoveries on loans previously charged-off	70		28
Net recoveries (charge-offs)	-301		-419
Provision (release) for loan losses	-35		271
Balance at end of period	4,588		5,500
Ending balance, loans individually evaluated for impairment	2,292	[1]	2,274	[1]	1,855
Ending balance, loans collectively evaluated for impairment	2,296		3,226
Recorded Investment in Loans, Ending balance, loans individually evaluated for impairment	12,761	[1]	13,430	[1]	12,466
Recorded Investment in Loans, Ending balance, loans collectively evaluated for impairment	125,973		134,144
Total loans	138,734		147,574
Personal [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	2,668		3,438
Loans charged-off	-10		-130
Recoveries on loans previously charged-off	873		406
Net recoveries (charge-offs)	863		276
Provision (release) for loan losses	-1,237		-626
Balance at end of period	2,294		3,088
Ending balance, loans individually evaluated for impairment	70	[1]	138	[1]	109
Ending balance, loans collectively evaluated for impairment	2,224		2,950
Recorded Investment in Loans, Ending balance, loans individually evaluated for impairment	318	[1]	625	[1]	430
Recorded Investment in Loans, Ending balance, loans collectively evaluated for impairment	202,749		207,124
Total loans	$203,067		$207,749
[1]	Refer to Note 4 for additional information regarding impaired loans.

Recovered_Sheet2

Allowance For Loan Losses And Reserve For Unfunded Commitments (Reserve For Unfunded Commitments) (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Reserve for Unfunded Commitments [Roll Forward]
Balance at beginning of period	$12,274	[1]	$9,206	[1]
Provision for unfunded commitments	376	[1]	496	[1]
Balance at end of period	12,650	[1]	9,702	[1]
Unfunded commitments, excluding covered assets, at period end	$6,229,242	[1]	$4,814,346	[1]
[1]	Unfunded commitments include commitments to extend credit, standby letters of credit and commercial letters of credit. Unfunded commitments related to covered assets are excluded as they are covered under a loss sharing agreement with the FDIC.

Recovered_Sheet3

Goodwill And Other Intangible Assets (Changes In The Carrying Amount Of Goodwill By Operating Segment) (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Goodwill [Line Items]
Goodwill	$94,041	$94,041
Banking [Member]
Goodwill [Line Items]
Goodwill	81,755	81,755
Asset Management [Member]
Goodwill [Line Items]
Goodwill	$12,286	$12,286

Recovered_Sheet4

Goodwill And Other Intangible Assets (Narrative) (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015
Goodwill And Other Intangible Assets [Line Items]
Goodwill, Impairment Loss	$0
Impairment of intangible assets	$0
Minimum [Member]
Goodwill And Other Intangible Assets [Line Items]
Intangible assets amortized estimated useful lives	8 years
Maximum [Member]
Goodwill And Other Intangible Assets [Line Items]
Intangible assets amortized estimated useful lives	12 years

Goodwill_And_Other_Intangible_2

Goodwill And Other Intangible Assets (Other Intangible Assets) (Detail) (USD $)	3 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Goodwill And Other Intangible Assets [Line Items]
Amortization during the period	$655	$756
Core Deposits Intangibles [Member]
Goodwill And Other Intangible Assets [Line Items]
Gross Carrying Amount	18,093		18,093
Accumulated Amortization	13,473		12,870
Net carrying amount	4,620		5,223
Amortization during the period	603		2,799
Weighted average remaining life (in years)	2 years		2 years
Customer Relationships [Member]
Goodwill And Other Intangible Assets [Line Items]
Gross Carrying Amount	2,002		2,002
Accumulated Amortization	1,392		1,340
Net carrying amount	610		662
Amortization during the period	$52		$208
Weighted average remaining life (in years)	6 years		6 years

Goodwill_And_Other_Intangible_3

Goodwill And Other Intangible Assets (Scheduled Amortization Of Other Intangible Assets) (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Finite-Lived Intangible Assets, Amortization Expense, Remaining Months	$1,800
2016	2,161
2017	1,125
2018	98
2019	28
2020 and thereafter	18
Total	$5,230	$5,885

Recovered_Sheet5

Short-Term and Secured Borrowings (Summary Of Short-Term Borrowings) (Detail) (USD $)	3 Months Ended		12 Months Ended
	Mar. 31, 2015		Dec. 31, 2014
Outstanding: [Abstract]
FHLB advances, short-term	$253,000,000		$428,000,000
Other borrowings, short-term	33,000		0
Short-term borrowings	253,033,000		428,000,000
Other Information: [Abstract]
Weighted average remaining maturity of FHLB advances at period end	9 months		7 months
Unused FHLB advances availability	552,721,000		265,529,000
Unused overnight federal funds availability	630,500,000	[1]	630,500,000	[1]
Borrowing capacity through the FRB discount window primary credit program	392,842,000	[2]	403,752,000	[2]
Narrative: [Abstract]
FHLB advances borrowing capacity	848,100,000
Revolving Line of Credit, Conversion to Term Loan, Conversion Date	25-Sep-15
Revolving Line of Credit, Conversion to Term Loan, Loan Interest Option Increment Over Libor	1.95%
Revolving Line of Credit, Conversion to Term Loan, Loan Interest Option Increment Under PRIME	0.50%
Revolving Line of Credit, Conversion to Term Loan, Term Loan Due Date	26-Sep-17
Secured borrowings, loan participation agreements	5,800,000		4,400,000
Federal Home Loan Bank of Atlanta [Member]
Outstanding: [Abstract]
FHLB advances, short-term	3,000,000
Narrative: [Abstract]
FHLB Advances	8,000,000
Federal Home Loan Bank of Chicago [Member]
Outstanding: [Abstract]
FHLB advances, short-term	250,000,000
Narrative: [Abstract]
FHLB Advances	295,000,000
Revolving Credit Facility [Member]
Narrative: [Abstract]
Revolving Line of Credit, maximum borrowing capacity	60,000,000
Revolving Line of Credit, Amount Outstanding	$0
Short-term Debt [Member]
Outstanding: [Abstract]
FHLB advances, rate	0.14%		0.13%
Other Short-Term Borrowing [Member]
Outstanding: [Abstract]
Other borrowings, rate	0.06%		0.00%
[1]	Our total availability of overnight Federal fund borrowings is not a committed line of credit and is dependent upon lender availability.
[2]	Our borrowing capacity changes each quarter subject to available collateral and FRB discount factors.

LONGTERM_DEBT_LongTerm_Debt_Sc

LONG-TERM DEBT Long-Term Debt (Schedule of Long-Term Debt) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Dec. 31, 2014
Debt Instrument [Line Items]
Long-term debt	$344,788		$344,788
Three Month Libor Plus Two Point Six Five Percentage [Member]
Debt Instrument [Line Items]
Increment Over Libor Of Long Term Debt	2.65%
Three Month Libor Plus One Point Seven One Percentage [Member]
Debt Instrument [Line Items]
Increment Over Libor Of Long Term Debt	1.71%
Three Month Libor Plus One Point Five Zero Percentage [Member]
Debt Instrument [Line Items]
Increment Over Libor Of Long Term Debt	1.50%
Parent Company [Member]
Debt Instrument [Line Items]
Long-term debt	294,788		294,788
Parent Company [Member] | Three Month Libor Plus Two Point Six Five Percentage [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.92%	[1]
Subordinated Borrowing, Due Date	17-Jun-34
Junior subordinated debentures	8,248	[1],[2]	8,248	[1],[2]
Parent Company [Member] | Three Month Libor Plus One Point Seven One Percentage [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	1.98%	[3]
Subordinated Borrowing, Due Date	15-Sep-35
Junior subordinated debentures	51,547	[2],[3]	51,547	[2],[3]
Parent Company [Member] | Three Month Libor Plus One Point Five Zero Percentage [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	1.77%	[4]
Subordinated Borrowing, Due Date	15-Dec-35
Junior subordinated debentures	41,238	[2],[4]	41,238	[2],[4]
Parent Company [Member] | Ten Point Zero Zero Percentage Junior Subordinated Debentures Due Two Zero Six Eight [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	10.00%	[2]
Subordinated Borrowing, Due Date	15-Jun-68
Junior subordinated debentures	68,755	[2]	68,755	[2]
Parent Company [Member] | Seven Point One Two Five Percentage Subordinated Debentures Due Two Zero Four Two [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.13%	[5]
Subordinated Borrowing, Due Date	30-Oct-42
Subordinated debentures	125,000	[5]	125,000	[5]
Subsidiaries [Member]
Debt Instrument [Line Items]
FHLB advances, long-term	$50,000		$50,000
[1]	Variable rate in effect at March 31, 2015 based on three-month LIBOR +2.65%.
[2]	Under the final regulatory capital rules issued in July 2013, these instruments are grandfathered for inclusion as a component of Tier 1 capital, although the Tier 1 capital treatment for these instruments will be subject to phase-out due to certain acquisitions.
[3]	Variable rate in effect at March 31, 2015, based on three-month LIBOR +1.71%.
[4]	Variable rate in effect at March 31, 2015, based on three-month LIBOR +1.50%.
[5]	Qualifies as Tier 2 capital for regulatory capital purposes.

LONGTERM_DEBT_Longterm_Debt_Na

LONG-TERM DEBT Long-term Debt (Narrative) (Details) (USD $)	Mar. 31, 2015
In Thousands, unless otherwise specified	trust
Debt [Line Items]
Number of wholly-owned trusts	4
Parent Company [Member]
Debt [Line Items]
Junior subordinated debentures	169,788	[1]
[1]	The trust preferred securities are subject to mandatory redemption, in whole or in part, upon repayment of the Debentures at maturity or upon their earlier redemption in whole or in part. The Debentures are redeemable in whole or in part prior to maturity at any time after the dates shown in the table and only after we have obtained Federal Reserve approval, if then required under applicable guidelines or regulations.

LONGTERM_DEBT_Maturity_and_Rat

LONG-TERM DEBT Maturity and Rate Schedule for FHLB Long-Term Advances (Details) (USD $)	Mar. 31, 2015		Dec. 31, 2014
September 2016 FHLB Advance Increase Option Date [Member]
Maturity and Rate Schedule of FHLB Long-term Advances [Table] [Line Items]
Forward Commitment Advance with FHLB	$150,000,000
December 2016 FHLB Advance Increase Option Date [Member] [Member]
Maturity and Rate Schedule of FHLB Long-term Advances [Table] [Line Items]
Forward Commitment Advance with FHLB	150,000,000
Long-term Debt [Member]
Maturity and Rate Schedule of FHLB Long-term Advances [Table] [Line Items]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Weighted Average Interest Rate	3.75%
Subsidiaries [Member]
Maturity and Rate Schedule of FHLB Long-term Advances [Table] [Line Items]
FHLB advances, long-term	50,000,000		50,000,000
March 25, 2019 [Member] | Subsidiaries [Member]
Maturity and Rate Schedule of FHLB Long-term Advances [Table] [Line Items]
FHLB advances, long-term	2,000,000
March 25, 2019 [Member] | Subsidiaries [Member] | Federal Home Loan Bank Advances [Member]
Maturity and Rate Schedule of FHLB Long-term Advances [Table] [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.26%
May 22, 2019 [Member] | Subsidiaries [Member]
Maturity and Rate Schedule of FHLB Long-term Advances [Table] [Line Items]
FHLB advances, long-term	3,000,000
May 22, 2019 [Member] | Subsidiaries [Member] | Federal Home Loan Bank Advances [Member]
Maturity and Rate Schedule of FHLB Long-term Advances [Table] [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.68%
September 12, 2019 [Member] | Subsidiaries [Member]
Maturity and Rate Schedule of FHLB Long-term Advances [Table] [Line Items]
FHLB advances, long-term	15,000,000	[1]
September 12, 2019 [Member] | Subsidiaries [Member] | Federal Home Loan Bank Advances [Member]
Maturity and Rate Schedule of FHLB Long-term Advances [Table] [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.72%	[1]
September 26, 2019 [Member] | Subsidiaries [Member]
Maturity and Rate Schedule of FHLB Long-term Advances [Table] [Line Items]
FHLB advances, long-term	15,000,000	[1]
September 26, 2019 [Member] | Subsidiaries [Member] | Federal Home Loan Bank Advances [Member]
Maturity and Rate Schedule of FHLB Long-term Advances [Table] [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.69%	[1]
December 9, 2019 [Member] | Subsidiaries [Member]
Maturity and Rate Schedule of FHLB Long-term Advances [Table] [Line Items]
FHLB advances, long-term	$15,000,000	[2]
December 9, 2019 [Member] | Subsidiaries [Member] | Federal Home Loan Bank Advances [Member]
Maturity and Rate Schedule of FHLB Long-term Advances [Table] [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.58%	[2]
[1]	Provides for a one-time option to increase the advances in September 2016, up to $150.0 million each at the same fixed rate as the original advance. The advances include prepayment features and are subject to a prepayment fee.
[2]	Provides for a one-time option to increase the advances in December 2016, up to $150.0 million each at the same fixed rate as the original advance. The advances include prepayment features and are subject to a prepayment fee.

LONGTERM_DEBT_Scheduled_Maturi

LONG-TERM DEBT Scheduled Maturities of Long-Term Debt (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Year ending December 31, [Abstract]
2019	$50,000
2020 and thereafter	294,788
Long-term debt	$344,788	$344,788

Recovered_Sheet6

Junior Subordinated Deferrable Interest Debentures Held By Trusts That Issued Guaranteed Capital Debt Securities (Narrative) (Detail)	3 Months Ended
	Mar. 31, 2015
Debt [Line Items]
Ownership percentage	100.00%
Number of wholly-owned trusts	4
PrivateBancorp Capital Trust IV [Member]
Debt [Line Items]
Debt Instrument, Covenant Description	Under the replacement capital covenant, as amended in October 2012, we committed, for the benefit of certain debt holders, that we would not repay, redeem or repurchase the 10% Debentures or the related Trust Preferred Securities prior to June 2048 unless we have (1) obtained any required regulatory approval, and (2) raised certain amounts of qualifying equity or equity-like replacement capital at any time after October 10, 2012.
Debt Instrument, Interest Rate, Stated Percentage	10.00%	[1]
Parent Company [Member] | Seven Point One Two Five Percentage Subordinated Debentures Due Two Zero Four Two [Member]
Debt [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.13%	[2]
Subordinated Borrowing, Due Date	30-Oct-42
[1]	Reflects the coupon rate in effect at March 31, 2015. The coupon rate for the Bloomfield Hills Statutory Trust I is a variable rate and is based on three-month LIBOR plus 2.65%. The coupon rates for the PrivateBancorp Statutory Trusts II and III are at a variable rate based on three-month LIBOR plus 1.71% for Trust II and three-month LIBOR plus 1.50% for Trust III. The coupon rate for the PrivateBancorp Capital Trust IV is fixed. Distributions for all of the Trusts are payable quarterly. We have the right to defer payment of interest on the Debentures at any time or from time to time for a period not exceeding ten years in the case of the Debentures held by Trust IV, and five years in the case of all other Debentures, without causing an event of default under the related indenture, provided no extension period may extend beyond the stated maturity of the Debentures. During such extension period, distributions on the trust preferred securities would also be deferred, and our ability to pay dividends on our common stock would generally be prohibited. The Federal Reserve has the ability to prevent interest payments on the Debentures.
[2]	Qualifies as Tier 2 capital for regulatory capital purposes.

Recovered_Sheet7

Junior Subordinated Deferrable Interest Debentures Held By Trusts That Issued Guaranteed Capital Debt Securities (Common Securities, Preferred Securities, And Related Debentures) (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Dec. 31, 2014
Junior Subordinated Deferrable Interest Debentures Held By Trusts That Issued Guaranteed Capital Debt Securities [Line Items]
Common securities issued	$77,968		$77,211
Bloomfield Hills Statutory Trust I [Member]
Junior Subordinated Deferrable Interest Debentures Held By Trusts That Issued Guaranteed Capital Debt Securities [Line Items]
Issuance Date	May 2004
Common securities issued	248
Trust Preferred Securities Issued	8,000	[1]
Coupon Rate	2.92%	[2]
Earliest Redemption Date (on or after)	17-Jun-09	[3]
Debentures, Maturity Date	Jun-34
Principal Amount of Debentures	8,248	[3]	8,248	[3]
PrivateBancorp Statutory Trust II [Member]
Junior Subordinated Deferrable Interest Debentures Held By Trusts That Issued Guaranteed Capital Debt Securities [Line Items]
Issuance Date	Jun. 2005
Common securities issued	1,547
Trust Preferred Securities Issued	50,000	[1]
Coupon Rate	1.98%	[2]
Earliest Redemption Date (on or after)	15-Sep-10	[3]
Debentures, Maturity Date	Sept. 2035
Principal Amount of Debentures	51,547	[3]	51,547	[3]
PrivateBancorp Statutory Trust III [Member]
Junior Subordinated Deferrable Interest Debentures Held By Trusts That Issued Guaranteed Capital Debt Securities [Line Items]
Issuance Date	Dec. 2005
Common securities issued	1,238
Trust Preferred Securities Issued	40,000	[1]
Coupon Rate	1.77%	[2]
Earliest Redemption Date (on or after)	15-Dec-10	[3]
Debentures, Maturity Date	Dec. 2035
Principal Amount of Debentures	41,238	[3]	41,238	[3]
PrivateBancorp Capital Trust IV [Member]
Junior Subordinated Deferrable Interest Debentures Held By Trusts That Issued Guaranteed Capital Debt Securities [Line Items]
Issuance Date	May 2008
Common securities issued	5
Trust Preferred Securities Issued	68,750	[1]
Coupon Rate	10.00%	[2]
Earliest Redemption Date (on or after)	15-Jun-13	[3]
Debentures, Maturity Date	Jun-68
Principal Amount of Debentures	68,755	[3]	68,755	[3]
Junior Subordinated Debt [Member]
Junior Subordinated Deferrable Interest Debentures Held By Trusts That Issued Guaranteed Capital Debt Securities [Line Items]
Common securities issued	3,038
Trust Preferred Securities Issued	166,750	[1]
Three Month Libor Plus Two Point Six Five Percentage [Member]
Junior Subordinated Deferrable Interest Debentures Held By Trusts That Issued Guaranteed Capital Debt Securities [Line Items]
Increment Over Libor Of Long Term Debt	2.65%
Three Month Libor Plus One Point Seven One Percentage [Member]
Junior Subordinated Deferrable Interest Debentures Held By Trusts That Issued Guaranteed Capital Debt Securities [Line Items]
Increment Over Libor Of Long Term Debt	1.71%
Three Month Libor Plus One Point Five Zero Percentage [Member]
Junior Subordinated Deferrable Interest Debentures Held By Trusts That Issued Guaranteed Capital Debt Securities [Line Items]
Increment Over Libor Of Long Term Debt	1.50%
Parent Company [Member]
Junior Subordinated Deferrable Interest Debentures Held By Trusts That Issued Guaranteed Capital Debt Securities [Line Items]
Principal Amount of Debentures	$169,788	[3]
Parent Company [Member] | Three Month Libor Plus Two Point Six Five Percentage [Member]
Junior Subordinated Deferrable Interest Debentures Held By Trusts That Issued Guaranteed Capital Debt Securities [Line Items]
Coupon Rate	2.92%	[4]
Parent Company [Member] | Three Month Libor Plus One Point Seven One Percentage [Member]
Junior Subordinated Deferrable Interest Debentures Held By Trusts That Issued Guaranteed Capital Debt Securities [Line Items]
Coupon Rate	1.98%	[5]
Parent Company [Member] | Three Month Libor Plus One Point Five Zero Percentage [Member]
Junior Subordinated Deferrable Interest Debentures Held By Trusts That Issued Guaranteed Capital Debt Securities [Line Items]
Coupon Rate	1.77%	[6]
[1]	The trust preferred securities accrue distributions at a rate equal to the interest rate on and have a maturity identical to that of the related Debentures. The trust preferred securities will be redeemed upon maturity or earlier redemption of the related Debentures.
[2]	Reflects the coupon rate in effect at March 31, 2015. The coupon rate for the Bloomfield Hills Statutory Trust I is a variable rate and is based on three-month LIBOR plus 2.65%. The coupon rates for the PrivateBancorp Statutory Trusts II and III are at a variable rate based on three-month LIBOR plus 1.71% for Trust II and three-month LIBOR plus 1.50% for Trust III. The coupon rate for the PrivateBancorp Capital Trust IV is fixed. Distributions for all of the Trusts are payable quarterly. We have the right to defer payment of interest on the Debentures at any time or from time to time for a period not exceeding ten years in the case of the Debentures held by Trust IV, and five years in the case of all other Debentures, without causing an event of default under the related indenture, provided no extension period may extend beyond the stated maturity of the Debentures. During such extension period, distributions on the trust preferred securities would also be deferred, and our ability to pay dividends on our common stock would generally be prohibited. The Federal Reserve has the ability to prevent interest payments on the Debentures.
[3]	The trust preferred securities are subject to mandatory redemption, in whole or in part, upon repayment of the Debentures at maturity or upon their earlier redemption in whole or in part. The Debentures are redeemable in whole or in part prior to maturity at any time after the dates shown in the table and only after we have obtained Federal Reserve approval, if then required under applicable guidelines or regulations.
[4]	Variable rate in effect at March 31, 2015 based on three-month LIBOR +2.65%.
[5]	Variable rate in effect at March 31, 2015, based on three-month LIBOR +1.71%.
[6]	Variable rate in effect at March 31, 2015, based on three-month LIBOR +1.50%.

Equity_Change_in_Accumulated_O

Equity (Change in Accumulated Other Comprehensive Income by Component) (Details) (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014		Dec. 31, 2014
Accumulated Other Comprehensive Income [Roll Forward]
Balance at beginning of period, Accumulated Other Comprehensive Income	$20,917		$9,844
Increase in unrealized gains (losses) on AFS securities	8,590		3,677
Increase in unrealized gains (losses) on cash flow hedges	8,630		4,137
Tax benefit (expense) on increase in unrealized gains (losses)	6,727		3,074
Other comprehensive income (loss) before reclassifications	10,493		4,740
Reclassification adjustment of net gains included in net income on AFS securities	-534		-331
Reclassification adjustment of net gains included in net income on cash flow hedges	-2,538		-2,043
Reclassification adjustment of net gains included in net income	-3,072	[1]	-2,374	[1]
Reclassification adjustment for tax expense on realized net gains	1,209	[2]	937	[2]
Amounts reclassified from AOCI	-1,863		-1,437
Net current period other comprehensive income (loss) on AFS securities	4,908		2,026
Net unrealized gains (losses) on cash flow hedges on cash flow hedges	3,722		1,277
Net current period other comprehensive income (loss)	8,630		3,303
Balance at end of period, Accumulated Other Comprehensive Income	29,547		13,147
Accumulated Other Comprehensive Income (Loss) (Narrative) [Abstract]
Nonvoting Common Stock, Shares Authorized	174,000,000				174,000,000
Treasury Stock, Shares	160,193				1,704
Unrealized Gain (Loss) on Available-for-Sale Securities [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Balance at beginning of period, Unrealized Gain (Loss) on Available-for-Sale Securities	19,448		12,960
Increase in unrealized gains (losses) on AFS securities	8,590		3,677
Tax benefit (expense) on increase in unrealized gains (losses) on AFS securities	-3,358		-1,451
Other comprehensive income (loss), before reclassifications on AFS securities	5,232		2,226
Reclassification adjustment of net gains included in net income on AFS securities	-534	[1]	-331	[1]
Reclassification adjustment for tax expense on realized net gains on AFS securities	210	[2]	131	[2]
Amount reclassified from AOCI on AFS securities	-324		-200
Net current period other comprehensive income (loss) on AFS securities	4,908		2,026
Balance at end of period, Unrealized Gain (Loss) on Available-for-Sale Securities	24,356		14,986
Accumulated Gain (Loss) on Effective Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Balance at beginning of period, Accumulated Gain (Loss) on Effective Cash Flow Hedges	1,469		-3,116
Increase in unrealized gains (losses) on cash flow hedges	8,630		4,137
Tax benefit (expense) on increase in unrealized gains (losses) on cash flow hedges	-3,369		-1,623
Other comprehensive income (loss), before reclassifications on cash flow hedges	5,261		2,514
Reclassification adjustment of net gains included in net income on cash flow hedges	-2,538	[1]	-2,043	[1]
Reclassification adjustment for tax expense on realized net gains on cash flow hedges	999	[2]	806	[2]
Amount reclassified from AOCI on cash flow hedges	-1,539		-1,237
Net unrealized gains (losses) on cash flow hedges on cash flow hedges	3,722		1,277
Balance at end of period, Accumulated Gain (Loss) on Effective Cash Flow Hedges	$5,191		($1,839)
Series B Preferred Stock [Member]
Accumulated Other Comprehensive Income (Loss) (Narrative) [Abstract]
Preferred Stock, Shares Authorized	1,000,000
Preferred Stock, Shares Outstanding	0
Nonvoting Common Stock [Member]
Accumulated Other Comprehensive Income (Loss) (Narrative) [Abstract]
Nonvoting Common Stock, Shares Authorized	5,000,000
Nonvoting Common Stock, Shares, Outstanding	0
[1]	The amounts reclassified from AOCI for the available-for-sale securities are included in net securities gains on the Consolidated Statements of Income, while the amounts reclassified from AOCI for cash flow hedges are included in interest income on loans on the Consolidated Statements of Income.
[2]	The tax expense amounts reclassified from AOCI in connection with the available-for-sale securities reclassification and cash flow hedges reclassification are included in income tax provision on the Consolidated Statements of Income.

Earnings_Per_Common_Share_Basi

Earnings Per Common Share (Basic and Diluted Earnings Per Common Share) (Detail) (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Basic earnings per common share
Net income (loss)	$41,484		$34,505
Net income (loss) allocated to participating stockholders	-463	[1]	-613	[1]
Net income (loss) allocated to common stockholders	41,021		33,892
Weighted-average common shares outstanding	77,407,000		76,675,000
Basic earnings per common share	$0.53		$0.44
Diluted earnings per common share
Diluted earnings applicable to common stockholders	$41,028	[2]	$33,897	[2]
Weighted-average common shares outstanding	77,407,000		76,675,000
Dilutive effect of stock awards	1,105,000	[3]	742,000	[3]
Weighted-average diluted common shares outstanding	78,512,000		77,417,000
Diluted earnings per common share	$0.52		$0.44
Employee Stock Option [Member]
Diluted earnings per common share
Antidilutive shares, excluded from computation	730,000		1,200,000
[1]	Participating stockholders are those that hold certain share-based payment awards that contain nonforfeitable rights to dividends or dividend equivalents. Such shares or units are considered participating securities (i.e., certain of the Company’s deferred and restricted stock units and nonvested restricted stock awards).
[2]	Net income allocated to common stockholders for basic and diluted earnings per share may differ under the two-class method as a result of adding common stock equivalents for options to dilutive shares outstanding, which alters the ratio used to allocate earnings to common stockholders and participating securities for the purposes of calculating diluted earnings per share.
[3]	For the quarters ended March 31, 2015 and 2014, the weighted-average outstanding non-participating securities of 730,000 and 1.2 million shares, respectively, were not included in the computation of diluted earnings per common share because their inclusion would have been antidilutive for the periods presented.

Income_Taxes_Income_Tax_Provis

Income Taxes (Income Tax Provision Analysis) (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Income Tax Disclosure [Abstract]
Income (loss) before income taxes	$66,718	$55,531
Income tax provision: [Abstract]
Current income tax provision	21,540	19,867
Deferred income tax provision (benefit)	3,694	1,159
Total income tax provision (benefit)	$25,234	$21,026
Effective tax rate	37.80%	37.90%

Income_Taxes_Narrative_Detail

Income Taxes (Narrative) (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Disclosure Income Taxes Narrative [Abstract]
Net deferred tax assets	$88,900,000	$98,200,000
Deferred Tax Assets, Valuation Allowance	0
Unrecognized tax benefits relating to uncertain tax positions	$212,000	$212,000

Derivative_Instruments_Notiona

Derivative Instruments (Notional Amounts and Fair Value of Derivative Instruments) (Details) (USD $)	Mar. 31, 2015		Dec. 31, 2014
In Thousands, unless otherwise specified
Derivative [Line Items]
Interest rate contracts, cash flow hedging, asset derivatives	$8,491		$4,542
Derivatives, not designated as hedging, asset derivatives	64,491		49,108
Netting adjustments	-16,375	[1]	-10,588	[1]
Total derivatives, asset derivatives	56,607		43,062
Interest rate contracts, cash flow hedging, liability derivatives	441		2,715
Derivatives, not designated as hedging, liability derivatives	65,531		49,321
Netting adjustments	-39,005	[1]	-25,269	[1]
Total derivatives, liability derivatives	26,967		26,767
Client-Related Derivatives [Member]
Derivative [Line Items]
Interest rate contracts, not designated as hedging, asset derivatives	54,821		42,879
Foreign exchange contracts, not designated as hedging, asset derivatives	9,056		5,183
Credit contracts, not designated as hedging, asset derivatives	20		19
Derivatives, not designated as hedging, asset derivatives	63,897		48,081
Interest rate contracts, not designated as hedging, liability derivatives	56,520		43,792
Foreign exchange contracts, not designated as hedging, liability derivatives	8,433		4,659
Credit contracts, not designated as hedging, liability derivatives	26		24
Derivatives, not designated as hedging, liability derivatives	64,979		48,475
Other End-User Derivatives [Member]
Derivative [Line Items]
Foreign exchange contracts, not designated as hedging, asset derivatives	115		241
Mortgage banking derivatives, not designated as hedging, asset derivatives	479		786
Derivatives, not designated as hedging, asset derivatives	594		1,027
Foreign exchange contracts, not designated as hedging, liability derivatives	18		45
Mortgage banking derivatives, not designated as hedging, liability derivatives	534		801
Derivatives, not designated as hedging, liability derivatives	552		846
Interest Rate Contract [Member]
Derivative [Line Items]
Netting adjustments	-10,462	[1]	-7,433	[1]
Netting adjustments	-36,426	[1]	-24,067	[1]
Foreign Exchange Contract [Member]
Derivative [Line Items]
Netting adjustments	-5,912	[1]	-3,154	[1]
Netting adjustments	-2,570	[1]	-1,202	[1]
Credit Contract [Member]
Derivative [Line Items]
Netting adjustments	-1	[1]	-1	[1]
Netting adjustments	-9	[1]	0	[1]
Designated as Hedging Instrument [Member] | Interest Rate Contract [Member] | Cash Flow Hedging [Member]
Derivative [Line Items]
Notional amount, asset derivatives	725,000	[2]	550,000	[2]
Notional amount, liability derivatives	75,000	[2]	250,000	[2]
Not Designated as Hedging Instrument [Member] | Interest Rate Contract [Member] | Client-Related Derivatives [Member]
Derivative [Line Items]
Notional amount, asset derivatives	3,982,438	[2]	3,881,202	[2]
Notional amount, liability derivatives	3,982,438	[2]	3,743,827	[2]
Not Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member] | Client-Related Derivatives [Member]
Derivative [Line Items]
Notional amount, asset derivatives	173,672	[2]	98,285	[2]
Notional amount, liability derivatives	149,430	[2]	86,582	[2]
Not Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member] | Other End-User Derivatives [Member]
Derivative [Line Items]
Notional amount, asset derivatives	10,937	[2]	18,551	[2]
Notional amount, liability derivatives	4,566	[2]	2,892	[2]
Not Designated as Hedging Instrument [Member] | Credit Contract [Member] | Client-Related Derivatives [Member]
Derivative [Line Items]
Notional amount, asset derivatives	94,241	[2]	98,478	[2]
Notional amount, liability derivatives	$110,426	[2]	$100,941	[2]
[1]	Represents end-user, client-related and cash flow hedging derivative contracts and related cash collateral entered into with the same counterparty and subject to a master netting agreement.
[2]	The remaining average notional amounts are shown for credit contracts.

Derivative_Instruments_Narrati

Derivative Instruments (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Derivative [Line Items]
Cash collateral pledged, offset against related derivative liabilities	$22,700,000
Cash collateral received, offset against related derivate assets	57,000
Derivative, Collateral, Obligation to Return Cash	90,000
Receivable for cash pledged, not offset against derivative fair values under master netting agreement	0
Gain (Loss) on Cash Flow Hedge Ineffectiveness, Net	0
Maximum Length of Time Hedged in Interest Rate Cash Flow Hedge	5 years
Gain (Loss) from Components Excluded from Assessment of Cash Flow Hedge Effectiveness, Net	0
Net deferred gains (losses), net of tax, recorded in AOCI expected to be reclassified into earnings during the next 12 months	-5,200,000
Gain (Loss) on Discontinuation of Interest Rate Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring, Net	0
Interest rate lock commitments	83,200,000
Forward commitments for the future delivery of residential mortgage loans	105,000,000
Foreign currency risk on loans	14,700,000
Minimum [Member]
Derivative [Line Items]
Written RPAs Range Of Internal Risk Ratings	1
Maximum [Member]
Derivative [Line Items]
Written RPAs Range Of Internal Risk Ratings	8
Mortgage Receivable [Member]
Derivative [Line Items]
Mortgage loans held-for-sale, par value	$21,811,000	$42,199,000

DERIVATIVE_INSTRUMENTS_Derivat

DERIVATIVE INSTRUMENTS Derivative Instruments (Offsetting of Derivative Assets and Liabilities) (Details) (USD $)	Mar. 31, 2015		Dec. 31, 2014
In Thousands, unless otherwise specified
Offsetting of Derivative Assets and Liabilities [Line Items]
Derivative assets, gross, subject to a master netting agreement	$69,840	[1]	$51,104	[1]
Derivative assets, not subject to a master netting agreement	3,142	[1]	2,546	[1]
Total derivative assets, gross, including not subject to master netting agreement	72,982	[1]	53,650	[1]
Derivative assets, gross offset	-16,375	[2]	-10,588	[2]
Derivative assets, net, subject to master netting agreement	53,465		40,516
Total derivative assets	56,607		43,062
Derivative assets, collateral, obligation to return financial securities	-721	[3],[4]	0	[3],[4]
Derivative assets, amount offset against collateral, subject to master netting agreement	52,744		40,516
Total derivative assets, amount offset against collateral, including not subject to master netting agreement	55,886		43,062
Derivative liabilities, gross, subject to master netting agreement	62,028	[1]	48,952	[1]
Derivative liabilities, not subject to master netting agreement	3,944	[1]	3,084	[1]
Total derivative liabilities, gross, including not subject to master netting agreement	65,972	[1]	52,036	[1]
Derivative liabilities, gross offset	-39,005	[2]	-25,269	[2]
Derivative liabilities, net, subject to master netting agreement	23,023		23,683
Derivative liabilities	26,967		26,767
Derivative liabilities, collateral, right to reclaim financial securities	-17,358	[3],[4]	-18,739	[3],[4]
Derivative liabilities, amount offset against collateral, subject to master netting agreement	5,665		4,944
Total derivative liabilities, amount offset against collateral, including not subject to master netting agreement	9,609		8,028
Interest Rate Contract [Member]
Offsetting of Derivative Assets and Liabilities [Line Items]
Derivative assets, gross, subject to a master netting agreement	63,312	[1]	47,421	[1]
Derivative assets, gross offset	-10,462	[2]	-7,433	[2]
Derivative assets, net, subject to master netting agreement	52,850		39,988
Derivative assets, collateral, obligation to return financial securities	-721	[3],[4]
Derivative assets, amount offset against collateral, subject to master netting agreement	52,129		39,988
Derivative liabilities, gross, subject to master netting agreement	56,961	[1]	46,507	[1]
Derivative liabilities, gross offset	-36,426	[2]	-24,067	[2]
Derivative liabilities, net, subject to master netting agreement	20,535		22,440
Derivative liabilities, collateral, right to reclaim financial securities	-15,482	[3],[4]	-17,755	[3],[4]
Derivative liabilities, amount offset against collateral, subject to master netting agreement	5,053		4,685
Foreign Exchange Contract [Member]
Offsetting of Derivative Assets and Liabilities [Line Items]
Derivative assets, gross, subject to a master netting agreement	6,508	[1]	3,664	[1]
Derivative assets, gross offset	-5,912	[2]	-3,154	[2]
Derivative assets, net, subject to master netting agreement	596		510
Derivative assets, amount offset against collateral, subject to master netting agreement	596		510
Derivative liabilities, gross, subject to master netting agreement	5,041	[1]	2,421	[1]
Derivative liabilities, gross offset	-2,570	[2]	-1,202	[2]
Derivative liabilities, net, subject to master netting agreement	2,471		1,219
Derivative liabilities, collateral, right to reclaim financial securities	-1,863	[3],[4]	-965	[3],[4]
Derivative liabilities, amount offset against collateral, subject to master netting agreement	608		254
Credit Contract [Member]
Offsetting of Derivative Assets and Liabilities [Line Items]
Derivative assets, gross, subject to a master netting agreement	20	[1]	19	[1]
Derivative assets, gross offset	-1	[2]	-1	[2]
Derivative assets, net, subject to master netting agreement	19		18
Derivative assets, amount offset against collateral, subject to master netting agreement	19		18
Derivative liabilities, gross, subject to master netting agreement	26	[1]	24	[1]
Derivative liabilities, gross offset	-9	[2]	0	[2]
Derivative liabilities, net, subject to master netting agreement	17		24
Derivative liabilities, collateral, right to reclaim financial securities	-13	[3],[4]	-19	[3],[4]
Derivative liabilities, amount offset against collateral, subject to master netting agreement	$4		$5
[1]	All derivative contracts are over-the-counter contracts.
[2]	Represents end-user, client-related and cash flow hedging derivative contracts and related cash collateral entered into with the same counterparty and subject to a master netting agreement.
[3]	Collateralization is determined at the counterparty level. If overcollateralization exists, the amount shown is limited to the fair value of the derivative.
[4]	Financial instruments are disclosed at fair value. Financial instrument collateral is allocated pro-rata amongst the derivative liabilities to which it relates.

Recovered_Sheet8

Derivative Instruments (Derivatives Subject To Credit Risk Contingency Features) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Description of Credit Risk Related Contingent Features [Abstract]
Fair Value of derivatives with credit contingency features in a net liability position	$13,291	$14,596
Collateral posted for those transactions in a net liability position	15,226	16,865
If credit risk contingency features were triggered: [Abstract]
Additional Collateral required to be posted to derivative counterparties	0	0
Outstanding derivative instruments that would be immediately settled	$13,291	$14,596

Derivative_Instruments_Change_

Derivative Instruments (Change In Accumulated Other Comprehensive Income Related To Interest Rate Swaps Designated As Cash Flow Hedge) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Accumulated Other Comprehensive Income [Roll Forward]
Accumulated unrealized gain (loss) at beginning of period, pre-tax	$2,405	($5,110)
Amount of gain (loss) recognized in AOCI (effective portion), pre-tax	8,630	4,137
Amount reclassified from AOCI to interest income on loans, pre-tax	-2,538	-2,043
Accumulated unrealized gain (loss) at end of period, pre-tax	8,497	-3,016
Accumulated unrealized gain (loss) at beginning of period, after-tax	1,469	-3,116
Amount of gain (loss) recognized in AOCI (effective portion), after-tax	5,261	2,514
Amount reclassified from AOCI to interest income on loans, after-tax	-1,539	-1,237
Accumulated unrealized gain (loss) at end of period, after-tax	$5,191	($1,839)

Derivative_Instruments_Risk_Pa

Derivative Instruments (Risk Participation Agreements) (Details) (USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Derivative [Line Items]
Fair value of written RPAs	$26	$24
Maximum potential amount of future undiscounted payments	$3,821	$3,927
Percent of maximum potential amount of future undiscounted payments covered by proceeds from liquidation of pledged collateral	24.00%	25.00%
Minimum [Member]
Derivative [Line Items]
Range of Risk Participation Agreement Terms to Maturity (in years)	1 year	1 year
Range of assigned internal risk ratings for written RPAs	2	2
Maximum [Member]
Derivative [Line Items]
Range of Risk Participation Agreement Terms to Maturity (in years)	4 years	4 years
Range of assigned internal risk ratings for written RPAs	7	7

Derivative_Instruments_Gain_Lo

Derivative Instruments (Gain (Loss) Recognized On Derivative Instruments Not Designated In Hedging Relationship) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Derivative [Line Items]
Client-related derivatives	$4,172	$4,083
End-user derivatives	1,010	-176
Total derivatives not designated in hedging relationship	5,182	3,907
Interest Rate Contract [Member]
Derivative [Line Items]
Client-related derivatives	2,363	2,510
Foreign Exchange Contract [Member]
Derivative [Line Items]
Client-related derivatives	1,753	1,415
End-user derivatives	1,050	6
Credit Contract [Member]
Derivative [Line Items]
Client-related derivatives	56	158
Mortgage Banking Derivatives [Member]
Derivative [Line Items]
End-user derivatives	($40)	($182)

Recovered_Sheet9

Commitments, Guarantees, And Contingent Liabilities (Contractual Or Notional Amounts Of Financial Instruments) (Detail) (USD $)	Mar. 31, 2015		Dec. 31, 2014
Commitments Guarantees And Contingent Liabilities [Line Items]
Commitments to extend credit	$5,837,840,000	[1]	$5,674,753,000	[1]
Letters of credit	402,148,000	[1]	377,566,000	[1]
Covered loan commitments	10,700,000		11,000,000
Financial standby [Member]
Commitments Guarantees And Contingent Liabilities [Line Items]
Letters of credit	359,716,000	[1]	334,175,000	[1]
Performance standby [Member]
Commitments Guarantees And Contingent Liabilities [Line Items]
Letters of credit	37,667,000	[1]	38,167,000	[1]
Commercial letters of credit [Member]
Commitments Guarantees And Contingent Liabilities [Line Items]
Letters of credit	4,765,000	[1]	5,224,000	[1]
Home equity lines [Member]
Commitments Guarantees And Contingent Liabilities [Line Items]
Commitments to extend credit	133,911,000	[1]	129,943,000	[1]
Residential 1-4 family construction [Member]
Commitments Guarantees And Contingent Liabilities [Line Items]
Commitments to extend credit	51,776,000	[1]	53,847,000	[1]
Commercial real estate, other construction and land development [Member]
Commitments Guarantees And Contingent Liabilities [Line Items]
Commitments to extend credit	1,205,048,000	[1]	1,123,123,000	[1]
Commercial and industrial [Member]
Commitments Guarantees And Contingent Liabilities [Line Items]
Commitments to extend credit	4,101,972,000	[1]	4,031,217,000	[1]
All other commitments [Member]
Commitments Guarantees And Contingent Liabilities [Line Items]
Commitments to extend credit	$345,133,000	[1]	$336,623,000	[1]
[1]	Includes covered loan commitments of $10.7 million and $11.0 million as of March 31, 2015 and December 31, 2014, respectively.

Recovered_Sheet10

Commitments, Guarantees, And Contingent Liabilities (Narrative) (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015
Disclosure Commitments Guarantees And Contingent Liabilities Narrative [Abstract]
Reserve for unfunded commitments	$12,700,000
Unamortized fees associated with standby letters of credit	2,600,000
Remaining weighted-average term, standby letters of credit	14 months
Remaining actual lives, standby letters of credit, minimum	1 year
Remaining actual lives, standby letters of credit, maximum	6 years
Unfunded commitments for contributions to CRA investments and other investment partnerships	20,200,000
Unfunded commitments for tax-credit investments	8,300,000
Maximum potential future payments guarantee obligation, credit card settlement guarantees	13,500,000
Contingency liability, settlement guarantee program	$0

Recovered_Sheet11

Estimated Fair Value Of Financial Instruments (Narrative) (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015		Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans updated for appraisal in excess	$500,000		$500,000
Appraisal value to be reviewed	250,000
Appraisal value subject to technical review	1,000,000
Transfers of Assets and Liabilities Between Fair Value Hierarchy Level 1 and Level 2	0
Loans Held-for-sale, Other	67,595,000	[1]	72,946,000	[1]
Participating Mortgages [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Held-for-sale, Other	67,600,000		36,600,000
Branch Closing, Sale [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Held-for-sale, Other			$36,300,000
[1]	Amounts at March 31, 2015 represent commercial, commercial real estate, and construction loans carried at the lower of aggregate cost or fair value. Generally, the Company intends to sell these loans within 30-60 days from the date the intent to sell was established. Amounts at December 31, 2014 consists of $36.6 million of commercial, commercial real estate and construction loans carried at the lower of aggregate cost or fair value and $36.3 million of commercial, commercial real estate, construction, home equity and personal loans held-for-sale in connection with the sale of the Company's banking office located in Norcross, Georgia, which closed in January 2015.

Recovered_Sheet12

Estimated Fair Value Of Financial Instruments (Fair Value Measurements On A Recurring Basis) (Detail) (USD $)	Mar. 31, 2015		Dec. 31, 2014
In Thousands, unless otherwise specified
Estimated Fair Value Of Financial Instruments [Line Items]
Securities available-for-sale, at fair value	$1,631,237		$1,645,344
Mortgages loans held-for-sale	21,866		42,215
Interest rate contract derivatives designated as hedging instruments	8,491		4,542
Other derivative assets, not designated as hedging instruments	64,491		49,108
Netting adjustments	-16,375	[1]	-10,588	[1]
Derivative assets	56,607		43,062
Total assets	1,709,710		1,730,621
Interest rate contract derivatives designated as hedging instruments	441		2,715
Netting adjustments	-39,005	[1]	-25,269	[1]
Derivative liabilities	26,967		26,767
Fair Value, Inputs, Level 1 [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Securities available-for-sale, at fair value	244,556		268,265
Mortgages loans held-for-sale	0		0
Derivative assets	0		0
Total assets	244,556		268,265
Derivative liabilities	0		0
Fair Value, Inputs, Level 2 [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Securities available-for-sale, at fair value	1,386,681		1,377,079
Mortgages loans held-for-sale	21,866		42,215
Interest rate contract derivatives designated as hedging instruments	8,491		4,542
Netting adjustments	-15,686		-9,952
Derivative assets	55,542		42,286
Total assets	1,464,089		1,461,580
Interest rate contract derivatives designated as hedging instruments	441		2,715
Netting adjustments	-38,316		-24,633
Derivative liabilities	26,950		26,727
Fair Value, Inputs, Level 3 [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Securities available-for-sale, at fair value	0		0
Mortgages loans held-for-sale	0		0
Netting adjustments	-689		-636
Derivative assets	1,065		776
Total assets	1,065		776
Netting adjustments	-689		-636
Derivative liabilities	17		40
U.S. Treasury Securities [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Securities available-for-sale, at fair value	244,556		268,265
U.S. Treasury Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Securities available-for-sale, at fair value	244,556		268,265
U.S. Agency [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Securities available-for-sale, at fair value	46,806		46,258
U.S. Agency [Member] | Fair Value, Inputs, Level 2 [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Securities available-for-sale, at fair value	46,806		46,258
Collateralized mortgage obligations [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Securities available-for-sale, at fair value	127,828		136,933
Collateralized mortgage obligations [Member] | Fair Value, Inputs, Level 2 [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Securities available-for-sale, at fair value	127,828		136,933
Residential mortgage-backed securities [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Securities available-for-sale, at fair value	829,413		846,078
Residential mortgage-backed securities [Member] | Fair Value, Inputs, Level 2 [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Securities available-for-sale, at fair value	829,413		846,078
State and municipal securities [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Securities available-for-sale, at fair value	382,134		347,310
State and municipal securities [Member] | Fair Value, Inputs, Level 2 [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Securities available-for-sale, at fair value	382,134		347,310
Foreign sovereign debt [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Securities available-for-sale, at fair value	500		500
Foreign sovereign debt [Member] | Fair Value, Inputs, Level 2 [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Securities available-for-sale, at fair value	500		500
Client-Related Derivatives [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Other derivative assets, not designated as hedging instruments	63,897		48,081
Other derivatives liabilities, not designated as hedging instruments	64,979		48,475
Client-Related Derivatives [Member] | Fair Value, Inputs, Level 2 [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Other derivative assets, not designated as hedging instruments	62,143		46,669
Other derivatives liabilities, not designated as hedging instruments	64,273		47,799
Client-Related Derivatives [Member] | Fair Value, Inputs, Level 3 [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Other derivative assets, not designated as hedging instruments	1,754		1,412
Other derivatives liabilities, not designated as hedging instruments	706		676
Other End-User Derivatives [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Other derivative assets, not designated as hedging instruments	594		1,027
Other derivatives liabilities, not designated as hedging instruments	552		846
Other End-User Derivatives [Member] | Fair Value, Inputs, Level 2 [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Other derivative assets, not designated as hedging instruments	594		1,027
Other derivatives liabilities, not designated as hedging instruments	$552		$846
[1]	Represents end-user, client-related and cash flow hedging derivative contracts and related cash collateral entered into with the same counterparty and subject to a master netting agreement.

Estimated_Fair_Value_Of_Financ2

Estimated Fair Value Of Financial Instruments (Reconciliation Of Beginning And Ending Fair Value For Those Fair Value Measurements Using Significant Unobservable Inputs (Level 3) (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Derivative Financial Instruments, Assets [Member]
Estimated Fair Value of Financial Instruments [Roll Forward]
Balance at beginning of period, derivative assets	$1,412	[1]	$448	[1]
Total gains (losses) included in earnings, derivative assets	312	[1],[2]	79	[1],[2]
Settlements, derivative assets	-500	[1]	-385	[1]
Transfers into Level 3 (out of Level 2) derivative assets	884	[1],[3]	827	[1],[3]
Transfers out of Level 3 (into Level 2), derivative assets	-354	[1],[3]	-112	[1],[3]
Balance at end of period, derivative assets	1,754	[1]	857	[1]
Change in unrealized gains (losses) in earnings relating to assets and liabilities still held at end of year	241	[1]	7	[1]
Derivative Financial Instruments, Liabilities [Member]
Estimated Fair Value of Financial Instruments [Roll Forward]
Balance at beginning of period, derivative liabilities	-676	[1]	-98	[1]
Total gains (losses) included in earnings, derivative liabilities	-24	[1],[2]	180	[1],[2]
Settlements, derivative liabilities	147	[1]	-245	[1]
Transfers into Level 3 (out of Level 2) derivative liabilities	-160	[1],[3]	-446	[1],[3]
Transfers out of Level 3 (into Level 2) derivative liabilities	8	[1],[3]	0	[1],[3]
Balance at end of period, derivative liabilities	-705	[1]	-609	[1]
Change in unrealized gains (losses) in earnings relating to assets and liabilities still held at end of year	$24	[1]	$166	[1]
[1]	Fair value is presented prior to giving effect to netting adjustments.
[2]	Amounts disclosed in this line are included in the Consolidated Statements of Income as capital markets products income for derivatives.
[3]	Transfers in and transfers out are recognized at the end of each quarterly reporting period. In general, derivative assets and liabilities are transferred into Level 3 from Level 2 due to a lack of observable market data, as there was deterioration in the credit risk of the derivative counterparty. Conversely, derivative assets and liabilities are transferred out of Level 3 into Level 2 due to an improvement in the credit risk of the derivative counterparty.

Estimated_Fair_Value_Of_Financ3

Estimated Fair Value Of Financial Instruments (Summary Of The Difference Between The Aggregate Fair Value And Remaining Principle Balance In Mortgage Loans Held For Sale) (Detail) (USD $)	Mar. 31, 2015		Dec. 31, 2014
In Thousands, unless otherwise specified
Estimated Fair Value Of Financial Instruments [Line Items]
Mortgages loans held-for-sale, aggregate fair value	$21,866		$42,215
Mortgage Receivable [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Mortgage loans held-for-sale, aggregate unpaid principal balance	21,811		42,199
Assets Held-for-sale [Member] | Mortgage Receivable [Member]
Estimated Fair Value Of Financial Instruments [Line Items]
Mortgage loans held-for-sale, difference	($55)	[1]	($16)	[1]
[1]	The change in fair value is reflected in mortgage banking non-interest income.

Estimated_Fair_Value_Of_Financ4

Estimated Fair Value Of Financial Instruments (Fair Value Measurements On A Nonrecurring Basis) (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Estimated Fair Value Of Financial Instruments [Line Items]
Collateral-dependent impaired loans, Fair Value	$27,234	[1]	$40,716	[1]
OREO, Fair Value	5,128	[2]	6,858	[2]
Total, Fair Value	32,362		47,574
Collateral-dependent impaired loans, (gains) losses	-1,653	[1]	5,612	[1]
OREO, Losses	935	[2]	1,463	[2]
Total, (gains) losses	($718)		$7,075
[1]	Represents the fair value of loans adjusted to the appraised value of the collateral with a write-down in fair value or change in specific reserves during the respective period. These fair value adjustments are recorded against the allowance for loan losses.
[2]	Represents the fair value of foreclosed properties that were adjusted subsequent to their initial classification as foreclosed assets. Write-downs are recognized as a component of net foreclosed real estate expense in the Consolidated Statements of Income.

Estimated_Fair_Value_Of_Financ5

Estimated Fair Value Of Financial Instruments (Quantitative Information Regarding Level 3 Fair Value Measurements) (Detail) (Fair Value, Inputs, Level 3 [Member], USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015
Watch List Derivatives [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	1,054
Watch List Derivatives [Member] | Minimum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range Of Inputs Significant Unobservable Inputs	4.50%
Watch List Derivatives [Member] | Maximum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range Of Inputs Significant Unobservable Inputs	16.50%
Watch List Derivatives [Member] | Weighted Average [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range Of Inputs Significant Unobservable Inputs	13.90%
Watch List Derivatives [Member] | Loss Factors [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Unobservable Input	Loss factors
Watch List Derivatives [Member] | Discounted Cash Flow [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Measurements, Valuation Techniques	Discounted cash flow
Risk Participation Agreements [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	-6	[1]
Risk Participation Agreements [Member] | Minimum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range Of Inputs Significant Unobservable Inputs	0.60%
Risk Participation Agreements [Member] | Maximum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range Of Inputs Significant Unobservable Inputs	16.50%
Risk Participation Agreements [Member] | Weighted Average [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range Of Inputs Significant Unobservable Inputs	4.00%
Risk Participation Agreements [Member] | Loss Factors [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Unobservable Input	Loss factors
Risk Participation Agreements [Member] | Discounted Cash Flow [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Measurements, Valuation Techniques	Discounted cash flow
Collateral Dependent Impaired Loans [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	27,234
Collateral Dependent Impaired Loans [Member] | Minimum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range Of Inputs Significant Unobservable Inputs	-2.00%
Collateral Dependent Impaired Loans [Member] | Maximum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range Of Inputs Significant Unobservable Inputs	-15.90%
Collateral Dependent Impaired Loans [Member] | Weighted Average [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range Of Inputs Significant Unobservable Inputs	-8.10%	[2]
Collateral Dependent Impaired Loans [Member] | Property Specific Adjustment [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Unobservable Input	Property specific adjustment
Collateral Dependent Impaired Loans [Member] | Sales Comparison, Income Capitalization And/Or Cost Approach [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Measurements, Valuation Techniques	Sales comparison, income capitalization and/or cost approach
Other Real Estate Owned [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	5,128
Other Real Estate Owned [Member] | Minimum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range Of Inputs Significant Unobservable Inputs	-2.40%
Other Real Estate Owned [Member] | Maximum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range Of Inputs Significant Unobservable Inputs	-18.80%
Other Real Estate Owned [Member] | Weighted Average [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range Of Inputs Significant Unobservable Inputs	-14.80%	[2]
Other Real Estate Owned [Member] | Property Specific Adjustment [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Unobservable Input	Property specific adjustment
Other Real Estate Owned [Member] | Sales Comparison, Income Capitalization And/Or Cost Approach [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Measurements, Valuation Techniques	Sales comparison, income capitalization and/or cost approach
[1]	Represents fair value of underlying swap.
[2]	Weighted average is calculated based on assets with a property specific adjustment.

Estimated_Fair_Value_Of_Financ6

Estimated Fair Value Of Financial Instruments (Financial Instruments) (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	$158,431	$132,211
Federal funds sold and interest-bearing deposits in banks	799,953	292,341
Loans held-for-sale	89,461	115,161
Securities available-for-sale, at fair value	1,631,237	1,645,344
Securities held-to-maturity, at amortized cost	1,159,853	1,129,285
Securities held-to-maturity, at fair value	1,173,402	1,132,615
Federal Home Loan Bank Stock	28,556	28,666
Loans, net of allowance for loan losses and unearned fees, carrying amount	12,013,874	11,739,721
Covered assets, net of allowance for covered loan losses	26,170	28,941
Accrued interest receivable	41,202	40,531
Investment in BOLI	55,561	55,207
Derivative assets	56,607	43,062
Deposits, carrying amount	14,101,728	13,089,968
Deposits held-for-sale	0	122,216
Short-term and secured borrowings, carrying amount	258,788	432,385
Secured borrowing fair value	5,800	4,400
Long-term debt	344,788	344,788
Accrued interest payable	7,004	6,948
Derivative liabilities	26,967	26,767
Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	158,431	132,211
Federal funds sold and interest-bearing deposits in banks	0	0
Loans held-for-sale	0	0
Securities available-for-sale, at fair value	244,556	268,265
Securities held-to-maturity, at fair value	0	0
Federal Home Loan Bank Stock, fair value	0	0
Loans, net of allowance for loan losses and unearned fees. fair value	0	0
Covered assets, net of allowance for covered loan losses, fair value	0	0
Accrued interest receivable	0	0
Investment in BOLI	0	0
Derivative assets	0	0
Deposits, fair value	0	0
Short-term and secured borrowings, fair value	0	0
Long-term debt, fair value	206,537	204,320
Accrued interest payable	0	0
Derivative liabilities	0	0
Fair Value, Inputs, Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	0	0
Federal funds sold and interest-bearing deposits in banks	799,953	292,341
Loans held-for-sale	89,461	115,161
Securities available-for-sale, at fair value	1,386,681	1,377,079
Securities held-to-maturity, at fair value	1,173,402	1,132,615
Federal Home Loan Bank Stock	28,556	28,666
Loans, net of allowance for loan losses and unearned fees. fair value	0	0
Covered assets, net of allowance for covered loan losses, fair value	0	0
Accrued interest receivable	0	0
Investment in BOLI	0	0
Derivative assets	55,542	42,286
Deposits, fair value	11,591,322	10,595,040
Deposits held-for-sale, fair value		117,572
Short-term and secured borrowings, fair value	252,675	427,150
Long-term debt, fair value	54,942	54,092
Accrued interest payable	0	0
Derivative liabilities	26,950	26,727
Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	0	0
Federal funds sold and interest-bearing deposits in banks	0	0
Loans held-for-sale	0	0
Securities available-for-sale, at fair value	0	0
Securities held-to-maturity, at fair value	0	0
Federal Home Loan Bank Stock, fair value	0	0
Loans, net of allowance for loan losses and unearned fees. fair value	11,951,864	11,736,461
Covered assets, net of allowance for covered loan losses, fair value	32,030	33,988
Accrued interest receivable	41,202	40,531
Investment in BOLI	55,561	55,207
Derivative assets	1,065	776
Deposits, fair value	2,519,320	2,500,617
Secured borrowing fair value	5,134	3,794
Long-term debt, fair value	77,041	73,962
Accrued interest payable	7,004	6,948
Derivative liabilities	17	40
Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	158,431	132,211
Federal funds sold and interest-bearing deposits in banks	799,953	292,341
Loans held-for-sale	89,461	115,161
Securities available-for-sale, at fair value	1,631,237	1,645,344
Securities held-to-maturity, at fair value	1,173,402	1,132,615
Federal Home Loan Bank Stock	28,556	28,666
Loans, net of allowance for loan losses and unearned fees. fair value	11,951,864	11,736,461
Covered assets, net of allowance for covered loan losses, fair value	32,030	33,988
Accrued interest receivable	41,202	40,531
Investment in BOLI	55,561	55,207
Derivative assets	56,607	43,062
Deposits, fair value	14,110,642	13,095,657
Deposits held-for-sale, fair value		117,572
Short-term and secured borrowings, carrying amount	257,809	430,944
Long-term debt, fair value	338,520	332,374
Accrued interest payable	7,004	6,948
Derivative liabilities	$26,967	$26,767

Operating_Segments_Operating_S

Operating Segments (Operating Segments Performance) (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Net interest income (loss)	$121,993		$108,752
Provision for loan and covered loan losses	5,646		3,707
Non-interest income	33,516		26,236
Non-interest expense	83,145		75,750
Income (loss) before income taxes	66,718		55,531
Income tax provision (benefit)	25,234		21,026
Net income (loss)	41,484		34,505
Assets	16,361,348			15,603,382
Total loans	12,170,484		10,924,985	11,892,219
Deposits, excluding deposits held-for-sale	14,101,728			13,089,968
Banking [Member]
Segment Reporting Information [Line Items]
Net interest income (loss)	126,498		115,152
Provision for loan and covered loan losses	5,646		3,707
Non-interest income	29,138		21,872
Non-interest expense	75,935		68,660
Income (loss) before income taxes	74,055		64,657
Income tax provision (benefit)	27,937		24,653
Net income (loss)	46,118		40,004
Assets	14,583,189			13,882,805
Total loans	12,170,484			11,892,219
Deposits, excluding deposits held-for-sale	14,156,257			13,150,600
Asset Management [Member]
Segment Reporting Information [Line Items]
Net interest income (loss)	899		787
Provision for loan and covered loan losses	0		0
Non-interest income	4,363		4,349
Non-interest expense	4,312		4,076
Income (loss) before income taxes	950		1,060
Income tax provision (benefit)	374		418
Net income (loss)	576		642
Holding Company And Other Adjustments [Member]
Segment Reporting Information [Line Items]
Net interest income (loss)	-5,404		-7,187
Provision for loan and covered loan losses	0		0
Non-interest income	15		15
Non-interest expense	2,898		3,014
Income (loss) before income taxes	-8,287		-10,186
Income tax provision (benefit)	-3,077		-4,045
Net income (loss)	-5,210		-6,141
Assets	1,778,159	[1]		1,720,577	[1]
Total loans	0			0
Deposits, excluding deposits held-for-sale	($54,529)	[1]		($60,632)	[1]
[1]	Deposit amounts represent the elimination of Holding Company cash accounts included in total deposits of the Banking segment.

Variable_Interest_Entities_Non

Variable Interest Entities (Nonconsolidated Variable Interest Entities) (Detail) (USD $)	Mar. 31, 2015		Dec. 31, 2014
In Thousands, unless otherwise specified
Variable Interest Entity [Line Items]
Carrying Amount	$234,605		$240,057
Maximum Exposure to Loss	71,972		80,369
Trust Preferred Capital Securities Issuances [Member]
Variable Interest Entity [Line Items]
Carrying Amount	169,788		169,788
Maximum Exposure to Loss	0		0
Community Reinvestment Investments [Member]
Variable Interest Entity [Line Items]
Carrying Amount	11,431		14,360
Maximum Exposure to Loss	13,125		16,054
Restructured loans to commercial clients, outstanding loan balance [Member]
Variable Interest Entity [Line Items]
Carrying Amount	50,425	[1]	49,376	[1]
Maximum Exposure to Loss	55,886	[1]	57,782	[1]
Restructured loans to commercial clients, related derivative asset [Member]
Variable Interest Entity [Line Items]
Carrying Amount	2,961	[1]	6,533	[1]
Maximum Exposure to Loss	$2,961	[1]	$6,533	[1]
[1]	Excludes personal loans and loans to non-for-profit entities.

Variable_Interest_Entities_Nar

Variable Interest Entities (Narrative) (Detail) (USD $)	3 Months Ended		12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Investment Holdings [Line Items]
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage	100.00%	100.00%
Tax Credit Investment Unfunded Commitments	$8,300,000
Impairment Losses, Tax Credit Investments	0		0
Low Income Housing Tax Credit Investment [Member]
Investment Holdings [Line Items]
Tax credit benefits, end of period, year	2031
Tax Credit Investments [Member]
Investment Holdings [Line Items]
Tax credit benefits, end of period, year	2029
Tax credit investments carrying value	9,900,000		10,000,000
Impairment Losses, Tax Credit Investments	$0	0