S&T Bancorp (STBA) 10-K 24 Feb 17 2016 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2016	Feb. 22, 2017	Jun. 30, 2016
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	FY
Entity Registrant Name	S&T BANCORP INC
Entity Central Index Key	719,220
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		34,913,023
Entity Public Float			$ 825,267,183

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
ASSETS
Cash and due from banks, including interest-bearing deposits of $87,201 and $41,639 at December 31, 2016 and 2015	$ 139,486	$ 99,399
Securities available-for-sale, at fair value	693,487	660,963
Loans held for sale	3,793	35,321
Portfolio loans, net of unearned income	5,611,419	5,027,612
Allowance for loan losses	(52,775)	(48,147)
Portfolio loans, net	5,558,644	4,979,465
Bank owned life insurance	72,081	70,175
Premises and equipment, net	44,999	49,127
Federal Home Loan Bank and other restricted stock, at cost	31,817	23,032
Goodwill	291,670	291,764
Other intangible assets, net	4,910	6,525
Other assets	102,166	102,583
Total Assets	6,943,053	6,318,354
LIABILITIES
Noninterest-bearing demand	1,263,833	1,227,766
Interest-bearing demand	638,300	616,188
Money market	936,461	605,184
Savings	1,050,131	1,061,265
Certificates of deposit	1,383,652	1,366,208
Total Deposits	5,272,377	4,876,611
Securities sold under repurchase agreements	50,832	62,086
Short-term borrowings	660,000	356,000
Long-term borrowings	14,713	117,043
Junior subordinated debt securities	45,619	45,619
Other liabilities	57,556	68,758
Total Liabilities	6,101,097	5,526,117
SHAREHOLDERS’ EQUITY
Common stock ($2.50 par value) Authorized—50,000,000 shares Issued—36,130,480 shares at December 31, 2016 and December 31, 2015 Outstanding—34,913,023 shares at December 31, 2016 and 34,810,374 shares at December 31, 2015	90,326	90,326
Additional paid-in capital	213,098	210,545
Retained earnings	585,891	544,228
Accumulated other comprehensive income (loss)	(13,784)	(16,457)
Treasury stock (1,217,457 shares at December 31, 2016 and 1,320,106 shares at December 31, 2015, at cost)	(33,575)	(36,405)
Total Shareholders’ Equity	841,956	792,237
Total Liabilities and Shareholders’ Equity	$ 6,943,053	$ 6,318,354

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Cash and due from banks, interest-bearing amounts	$ 87,201	$ 41,639
Common stock, par value (in dollars per share)	$ 2.50	$ 2.50
Common stock, shares authorized (in shares)	50,000,000	50,000,000
Common stock, shares issued (in shares)	36,130,480	36,130,480
Common stock, shares outstanding (in shares)	34,913,023	34,810,374
Treasury stock, shares (in shares)	1,217,457	1,320,106

Consolidated Statements of Net

Consolidated Statements of Net Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
INTEREST INCOME
Loans, including fees	$ 212,301	$ 188,012	$ 147,293
Investment Securities:
Taxable	10,340	9,792	8,983
Tax-exempt	3,658	3,954	3,857
Dividends	1,475	1,790	390
Total Interest Income	227,774	203,548	160,523
INTEREST EXPENSE
Deposits	19,692	12,944	10,128
Borrowings and junior subordinated debt securities	4,823	3,053	2,353
Total Interest Expense	24,515	15,997	12,481
NET INTEREST INCOME	203,259	187,551	148,042
Provision for loan losses	17,965	10,388	1,715
Net Interest Income After Provision for Loan Losses	185,294	177,163	146,327
NONINTEREST INCOME
Securities (losses) gains, net	0	(34)	41
Service charges on deposit accounts	12,512	11,642	10,559
Debit and credit card fees	11,943	12,113	10,781
Wealth management fees	10,456	11,444	11,343
Insurance fees	5,253	5,500	5,955
Mortgage banking	2,879	2,554	917
Gain on sale of credit card portfolio	2,066	0	0
Other	9,526	7,814	6,742
Total Noninterest Income	54,635	51,033	46,338
NONINTEREST EXPENSE
Salaries and employee benefits	77,325	68,252	60,442
Net occupancy	11,057	10,652	8,211
Data processing	9,047	9,677	8,737
Furniture and equipment	7,290	6,093	5,317
Professional services and legal	4,212	3,365	3,717
Other taxes	4,050	3,616	2,905
FDIC insurance	3,984	3,416	2,436
Marketing	3,713	4,224	3,316
Merger related expenses	0	3,167	689
Other	22,554	24,255	21,470
Total Noninterest Expense	143,232	136,717	117,240
Income Before Taxes	96,697	91,479	75,425
Provision for income taxes	25,305	24,398	17,515
Net Income Available to Common Shareholders	$ 71,392	$ 67,081	$ 57,910
Earnings per common share—basic (in USD per share)	$ 2.06	$ 1.98	$ 1.95
Earnings per common share—diluted (in USD per share)	2.05	1.98	1.95
Dividends declared per common share (in USD per share)	$ 0.77	$ 0.73	$ 0.68

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Net Income	$ 71,392	$ 67,081	$ 57,910
Other Comprehensive Income (Loss), Before Tax:
Net change in unrealized gains on securities available-for-sale	(2,899)	(663)	11,825
Net available-for-sale securities losses (gains) reclassified into earnings	0	34	(41)
Adjustment to funded status of employee benefit plans	6,974	(3,551)	(13,394)
Other Comprehensive Income (Loss), Before Tax	4,075	(4,180)	(1,610)
Income tax (expense) benefit related to items of other comprehensive income	(1,402)	1,556	471
Other Comprehensive Income (Loss), After Tax	2,673	(2,624)	(1,139)
Comprehensive Income	$ 74,065	$ 64,457	$ 56,771

Consolidated Statements of Chan

Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury Stock
Beginning balance at Dec. 31, 2013	$ 571,306	$ 77,993	$ 78,140	$ 468,158	$ (12,694)	$ (40,291)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	57,910			57,910
Other comprehensive income (loss), net of tax	(1,139)				(1,139)
Cash dividends declared	(20,203)			(20,203)
Treasury stock issued	(163)			(1,805)		1,642
Recognition of restricted stock compensation expense	933		933
Tax benefit from stock-based compensation	16		16
Issuance costs	(271)		(271)
Ending balance at Dec. 31, 2014	608,389	77,993	78,818	504,060	(13,833)	(38,649)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	67,081			67,081
Other comprehensive income (loss), net of tax	(2,624)				(2,624)
Cash dividends declared	(24,487)			(24,487)
Common stock issued in acquisition	142,469	12,333	130,136
Treasury stock issued	(182)			(2,426)		2,244
Recognition of restricted stock compensation expense	1,670		1,670
Tax benefit from stock-based compensation	53		53
Issuance costs	(132)		(132)
Ending balance at Dec. 31, 2015	792,237	90,326	210,545	544,228	(16,457)	(36,405)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	71,392			71,392
Other comprehensive income (loss), net of tax	2,673				2,673
Cash dividends declared	(26,784)			(26,784)
Treasury stock issued	(115)			(2,945)		2,830
Recognition of restricted stock compensation expense	2,544		2,544	0		0
Tax benefit from stock-based compensation	9		9
Ending balance at Dec. 31, 2016	$ 841,956	$ 90,326	$ 213,098	$ 585,891	$ (13,784)	$ (33,575)

Consolidated Statements of Cha7

Consolidated Statements of Changes in Shareholders' Equity (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash dividends declared, per share (in USD per share)	$ 0.77	$ 0.73	$ 0.68
Treasury stock (in shares)	102,649	80,862	58,762
Common Stock
Common stock issued in acquisition (in shares)		4,933,115

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
OPERATING ACTIVITIES
Net Income	$ 71,392	$ 67,081	$ 57,910
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	17,965	10,388	1,715
Provision for unfunded loan commitments	65	258	(655)
Net depreciation, amortization and accretion	3,628	356	4,703
Net amortization of discounts and premiums on securities	3,829	3,600	3,680
Stock-based compensation expense	2,544	1,636	975
Securities losses, (gains), net	0	34	(41)
Net gain on sale of credit card portfolio	(2,066)	0	0
Pension plan curtailment gain	(1,017)	0	0
Tax benefit from stock-based compensation	(9)	(53)	(16)
Mortgage loans originated for sale	(106,020)	(107,489)	(42,842)
Proceeds from the sale of loans	108,209	99,458	42,361
Deferred income taxes	536	(427)	1,536
Gain on sale of fixed assets	0	(179)	(33)
Gain on the sale of loans, net	(1,621)	(1,044)	(353)
Net increase in interest receivable	(2,409)	(2,744)	(933)
Net increase (decrease) in interest payable	1,715	(193)	(127)
Net decrease (increase) in other assets	4,668	(11,396)	7,628
Net (decrease) increase in other liabilities	(4,613)	1,298	2,595
Net Cash Provided by Operating Activities	96,796	60,584	78,103
INVESTING ACTIVITIES
Proceeds from maturities, prepayments and calls of securities available-for-sale	74,110	50,142	57,092
Proceeds from sales of securities available-for-sale	0	11,119	1,418
Purchases of securities available-for-sale	(113,362)	(74,712)	(181,213)
Net purchases of Federal Home Loan Bank stock	(8,784)	(855)	(1,506)
Net increase in loans	(599,341)	(383,575)	(313,264)
Proceeds from the sale of loans not originated for resale	9,208	2,880	5,408
Purchases of premises and equipment	(3,560)	(5,133)	(5,079)
Proceeds from the sale of premises and equipment	57	467	96
Net cash paid in excess of cash acquired from bank merger	0	(16,347)	0
Proceeds from the sale of credit card portfolio	25,019	0	0
Proceeds from surrender of bank owned life insurance	0	10,277	0
Net Cash Used in Investing Activities	(616,653)	(405,737)	(437,048)
FINANCING ACTIVITIES
Net increase in core deposits	378,323	195,589	240,948
Net increase (decrease) in certificates of deposit	18,095	51,209	(4,549)
Net increase (decrease) in short-term borrowings	304,000	(2,660)	150,000
Net (decrease) increase in securities sold under repurchase agreements	(11,254)	31,481	(3,242)
Proceeds from long-term borrowings	0	100,000	0
Repayments of long-term borrowings	(102,330)	(2,399)	(2,367)
Repayment of junior subordinated debt	0	(13,500)	0
Treasury shares issued-net	115	182	163
Common stock Issuance costs	0	(132)	(271)
Cash dividends paid to common shareholders	(26,784)	(24,487)	(20,203)
Tax benefit from stock-based compensation	9	53	16
Net Cash Provided by (Used in) Financing Activities	559,944	334,972	360,169
Net increase (decrease) in cash and cash equivalents	40,087	(10,181)	1,224
Cash and cash equivalents at beginning of year	99,399	109,580	108,356
Cash and Cash Equivalents at End of Year	139,486	99,399	109,580
Supplemental Disclosures
Transfers to other real estate owned and other repossessed assets	1,039	843	586
Interest paid	22,800	15,878	12,609
Income taxes paid, net of refunds	26,743	23,175	18,075
Loans transferred to held for sale	250	23,277	0
Loans transferred to portfolio from held for sale	7,933	0	0
Net assets (liabilities) from acquisitions, excluding cash and cash equivalents	$ 0	$ 43,433	$ 0

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Nature of Operations S&T Bancorp, Inc., or S&T, was incorporated on March 17, 1983 under the laws of the Commonwealth of Pennsylvania as a bank holding company and has three wholly owned subsidiaries, S&T Bank, 9th Street Holdings, Inc. and STBA Capital Trust I. We own a 50 percent interest in Commonwealth Trust Credit Life Insurance Company, or CTCLIC. We are presently engaged in nonbanking activities through the following five entities: 9th Street Holdings, Inc.; S&T Bancholdings, Inc.; CTCLIC; S&T Insurance Group, LLC and Stewart Capital Advisors, LLC. 9th Street Holdings, Inc. and S&T Bancholdings, Inc. are investment holding companies. CTCLIC, which is a joint venture with another financial institution, acts as a reinsurer of credit life, accident and health insurance policies sold by S&T Bank and the other institution. S&T Insurance Group, LLC, through its subsidiaries, offers a variety of insurance products. Stewart Capital Advisors, LLC is a registered investment advisor that manages private investment accounts for individuals and institutions. On October 29, 2014, S&T and Integrity Bancshares, Inc., or Integrity, based in Camp Hill, Pennsylvania, entered into an agreement to acquire Integrity Bancshares, Inc. and the transaction was completed on March 4, 2015. Integrity Bank was subsequently merged into S&T Bank on May 8, 2015. S&T Bank is operating under the name "Integrity Bank - A Division of S&T Bank" in south-central Pennsylvania. Accounting Policies Our financial statements have been prepared in accordance with U.S. generally accepted accounting principles, or GAAP. In preparing the financial statements, management is required to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities as of the dates of the balance sheets and revenues and expenses for the periods then ended. Actual results could differ from those estimates. Our significant accounting policies are described below. Principles of Consolidation The Consolidated Financial Statements include the accounts of S&T and its wholly owned subsidiaries. All significant intercompany transactions have been eliminated in consolidation. Investments of 20 percent to 50 percent of the outstanding common stock of investees are accounted for using the equity method of accounting. Reclassification Amounts in prior years' period financial statements and footnotes are reclassified whenever necessary to conform to the current year’s presentation. Reclassifications had no effect on our results of operations or financial condition. Business Combinations We account for business combinations using the acquisition method of accounting. Under this method of accounting, the acquired company’s net assets are recorded at fair value at the date of acquisition, and the results of operations of the acquired company are combined with our results from that date forward. Acquisition costs are expensed when incurred. The difference between the purchase price and the fair value of the net assets acquired (including identified intangibles) is recorded as goodwill. Fair Value Measurements We use fair value measurements when recording and disclosing certain financial assets and liabilities. Securities available-for-sale, trading assets and derivative financial instruments are recorded at fair value on a recurring basis. Additionally, from time to time, we may be required to record other assets at fair value on a nonrecurring basis, such as loans held for sale, impaired loans, other real estate owned, or OREO, and other repossessed assets, mortgage servicing rights, or MSRs, and certain other assets. Fair value is the price that would be received to sell an asset or paid to transfer a liability in the principal or most advantageous market in an orderly transaction between market participants at the measurement date. An orderly transaction is a transaction that assumes exposure to the market for a period prior to the measurement date to allow for marketing activities that are usual and customary for transactions involving such assets or liabilities; it is not a forced transaction. In determining fair value, we use various valuation approaches, including market, income and cost approaches. The fair value standard establishes a hierarchy for inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that observable inputs be used when available. Observable inputs are inputs that market participants would use in pricing an asset or liability, which are developed based on market data we have obtained from independent sources. Unobservable inputs reflect our estimates of assumptions that market participants would use in pricing an asset or liability, which are developed based on the best information available in the circumstances. The fair value hierarchy gives the highest priority to unadjusted quoted market prices in active markets for identical assets or liabilities (Level 1 measurement) and the lowest priority to unobservable inputs (Level 3 measurement). The fair value hierarchy is broken down into three levels based on the reliability of inputs as follows: Level 1: valuation is based upon unadjusted quoted market prices for identical instruments traded in active markets. Level 2: valuation is based upon quoted market prices for similar instruments traded in active markets, quoted market prices for identical or similar instruments traded in markets that are not active and model-based valuation techniques for which all significant assumptions are observable in the market or can be corroborated by market data. Level 3: valuation is derived from other valuation methodologies, including discounted cash flow models and similar techniques that use significant assumptions not observable in the market. These unobservable assumptions reflect estimates of assumptions that market participants would use in determining fair value. A financial instrument’s level within the fair value hierarchy is based on the lowest level of input that is significant to the fair value measurement. Our policy is to recognize transfers between any of the fair value hierarchy levels at the end of the reporting period in which the transfer occurred. The following are descriptions of the valuation methodologies that we use for financial instruments recorded at fair value on either a recurring or nonrecurring basis. Recurring Basis Securities Available-for-Sale Securities available-for-sale include both debt and equity securities. We obtain fair values for debt securities from a third-party pricing service which utilizes several sources for valuing fixed-income securities. We validate prices received from our pricing service through comparison to a secondary pricing service and broker quotes. We review the methodologies of the pricing service which provides us with a sufficient understanding of the valuation models, assumptions, inputs and pricing to reasonably measure the fair value of our debt securities. The market evaluation sources for debt securities include observable inputs rather than significant unobservable inputs and are classified as Level 2. The service provider utilizes pricing models that vary by asset class and include available trade, bid and other market information. Generally, the methodologies include broker quotes, proprietary models, and vast descriptive terms and conditions databases, and extensive quality control programs. Marketable equity securities that have an active, quotable market are classified as Level 1. Marketable equity securities that are quotable, but are thinly traded or inactive, are classified as Level 2. Marketable equity securities that are not readily traded and do not have a quotable market are classified as Level 3. Trading Assets We use quoted market prices to determine the fair value of our trading assets. Our trading assets are held in a Rabbi Trust under a deferred compensation plan and are invested in readily quoted mutual funds. Accordingly, these assets are classified as Level 1. Derivative Financial Instruments We use derivative instruments, including interest rate swaps for commercial loans with our customers, interest rate lock commitments and the sale of mortgage loans in the secondary market. We calculate the fair value for derivatives using widely accepted valuation techniques, including discounted cash flow analysis on the expected cash flows of each derivative. Each valuation considers the contractual terms of the derivative, including the period to maturity, and uses observable market based inputs, such as interest rate curves and implied volatilities. Accordingly, derivatives are classified as Level 2. We incorporate credit valuation adjustments into the valuation models to appropriately reflect both our own nonperformance risk and the respective counterparties’ nonperformance risk in calculating fair value measurements. In adjusting the fair value of our derivative contracts for the effect of nonperformance risk, we have considered the impact of netting and any applicable credit enhancements and collateral postings. Nonrecurring Basis Loans Held for Sale Loans held for sale consist of 1-4 family residential loans originated for sale in the secondary market and, from time to time, certain loans transferred from the loan portfolio to loans held for sale, all of which are carried at the lower of cost or fair value. The fair value of 1-4 family residential loans is based on the principal or most advantageous market currently offered for similar loans using observable market data. The fair value of the loans transferred from the loan portfolio is based on the amounts offered for these loans in currently pending sales transactions. Loans held for sale carried at fair value are classified as Level 3. Impaired Loans Impaired loans are carried at the lower of carrying value or fair value. Fair value is determined as the recorded investment balance less any specific reserve. We establish specific reserves based on the following three impairment methods: 1) the present value of expected future cash flows discounted at the loan’s original effective interest rate; 2) the loan’s observable market price; or 3) the fair value of the collateral less estimated selling costs when the loan is collateral dependent and we expect to liquidate the collateral. However, if repayment is expected to come from the operation of the collateral, rather than liquidation, then we do not consider estimated selling costs in determining the fair value of the collateral. Collateral values are generally based upon appraisals by approved, independent state certified appraisers. Appraisals may be discounted based on our historical knowledge, changes in market conditions from the time of appraisal or our knowledge of the borrower and the borrower’s business. Impaired loans carried at fair value are classified as Level 3. OREO and Other Repossessed Assets OREO and other repossessed assets obtained in partial or total satisfaction of a loan are recorded at the lower of recorded investment in the loan or fair value less cost to sell. Subsequent to foreclosure, these assets are carried at the lower of the amount recorded at acquisition date or fair value less cost to sell. Accordingly, it may be necessary to record nonrecurring fair value adjustments. Fair value, when recorded, is generally based upon appraisals by approved, independent state certified appraisers. Like impaired loans, appraisals on OREO may be discounted based on our historical knowledge, changes in market conditions from the time of appraisal or other information available to us. OREO and other repossessed assets carried at fair value are classified as Level 3. Mortgage Servicing Rights The fair value of MSRs is determined by calculating the present value of estimated future net servicing cash flows, considering expected mortgage loan prepayment rates, discount rates, servicing costs and other economic factors, which are determined based on current market conditions. The expected rate of mortgage loan prepayments is the most significant factor driving the value of MSRs. MSRs are considered impaired if the carrying value exceeds fair value. The valuation model includes significant unobservable inputs; therefore, MSRs are classified as Level 3. Other Assets We measure certain other assets at fair value on a nonrecurring basis. Fair value is based on the application of lower of cost or fair value accounting, or write-downs of individual assets. Valuation methodologies used to measure fair value are consistent with overall principles of fair value accounting and consistent with those described above. Financial Instruments In addition to financial instruments recorded at fair value in our financial statements, fair value accounting guidance requires disclosure of the fair value of all of an entity’s assets and liabilities that are considered financial instruments. The majority of our assets and liabilities are considered financial instruments. Many of these instruments lack an available trading market as characterized by a willing buyer and willing seller engaged in an exchange transaction. Also, it is our general practice and intent to hold our financial instruments to maturity and to not engage in trading or sales activities with respect to such financial instruments. For fair value disclosure purposes, we substantially utilize the fair value measurement criteria as required and explained above. In cases where quoted fair values are not available, we use present value methods to determine the fair value of our financial instruments. Cash and Cash Equivalents The carrying amounts reported in the Consolidated Balance Sheets for cash and due from banks, including interest-bearing deposits, approximate fair value. Loans The fair value of variable rate performing loans that may reprice frequently at short-term market rates is based on carrying values adjusted for credit risk. The fair value of variable rate performing loans that reprice at intervals of one year or longer, such as adjustable rate mortgage products, is estimated using discounted cash flow analyses that utilize interest rates currently being offered for similar loans and adjusted for credit risk. The fair value of fixed rate performing loans is estimated using a discounted cash flow analysis that utilizes interest rates currently being offered for similar loans and adjusted for credit risk. The fair value of nonperforming loans is the carrying value less any specific reserve on the loan if it is impaired. The carrying amount of accrued interest approximates fair value. Bank Owned Life Insurance Fair value approximates net cash surrender value of bank owned life insurance, or BOLI. Federal Home Loan Bank, or FHLB, and Other Restricted Stock It is not practical to determine the fair value of our FHLB and other restricted stock due to the restrictions placed on the transferability of these stocks; it is presented at carrying value. Deposits The fair values disclosed for deposits without defined maturities (e.g., noninterest and interest-bearing demand, money market and savings accounts) are by definition equal to the amounts payable on demand. The carrying amounts for variable rate, fixed-term time deposits approximate their fair values. Estimated fair values for fixed rate and other time deposits are based on discounted cash flow analysis using interest rates currently offered for time deposits with similar terms. The carrying amount of accrued interest approximates fair value. Short-Term Borrowings The carrying amounts of securities sold under repurchase agreements, or REPOs, and other short-term borrowings approximate their fair values. Long-Term Borrowings The fair values disclosed for fixed rate long-term borrowings are determined by discounting their contractual cash flows using current interest rates for long-term borrowings of similar remaining maturities. The carrying amounts of variable rate long-term borrowings approximate their fair values. Junior Subordinated Debt Securities The interest rate on the variable rate junior subordinated debt securities is reset quarterly; therefore, the carrying values approximate their fair values. Loan Commitments and Standby Letters of Credit Off-balance sheet financial instruments consist of commitments to extend credit and letters of credit. Except for interest rate lock commitments, estimates of the fair value of these off-balance sheet items are not made because of the short-term nature of these arrangements and the credit standing of the counterparties. Other Estimates of fair value are not made for items that are not defined as financial instruments, including such items as our core deposit intangibles and the value of our trust operations. Cash and Cash Equivalents We consider cash and due from banks, interest-bearing deposits with banks and federal funds sold as cash and cash equivalents. Securities We determine the appropriate classification of securities at the time of purchase. All securities, including both debt and equity securities, are classified as available-for-sale. These are securities that we intend to hold for an indefinite period of time, but that may be sold in response to changes in interest rates, prepayment risk, liquidity needs or other factors. Such securities are carried at fair value with net unrealized gains and losses deemed to be temporary and reported as a component of other comprehensive income (loss), net of tax. Realized gains and losses on the sale of available-for-sale securities and other-than-temporary impairment, or OTTI, charges are recorded within noninterest income in the Consolidated Statements of Net Income. Realized gains and losses on the sale of securities are determined using the specific-identification method. Bond premiums are amortized to the call date and bond discounts are accreted to the maturity date, both on a level yield basis. An investment security is considered impaired if its fair value is less than its cost or amortized cost basis. We perform a quarterly review of our securities to identify those that may indicate an OTTI. Our policy for OTTI within the marketable equity securities portfolio generally requires an impairment charge when the security is in a loss position for 12 consecutive months, unless facts and circumstances would suggest the need for an OTTI prior to that time. Our policy for OTTI within the debt securities portfolio is based upon a number of factors, including but not limited to, the length of time and extent to which the estimated fair value has been less than cost, the financial condition of the underlying issuer, the ability of the issuer to meet contractual obligations, the best estimate of the impairment charge representing credit losses, the likelihood of the security’s ability to recover any decline in its estimated fair value and whether management intends to sell the security or if it is more likely than not that management will be required to sell the investment security prior to the security’s recovery of any decline in its estimated fair value. If the impairment is considered other-than-temporary based on management’s review, the impairment must be separated into credit and non-credit components. The credit component is recognized in the Consolidated Statements of Net Income and the non-credit component is recognized in other comprehensive income (loss), net of applicable taxes. Loans Held for Sale Loans held for sale consist of 1-4 family residential loans originated for sale in the secondary market and, from time to time, certain loans transferred from the loan portfolio to loans held for sale, all of which are carried at the lower of cost or fair value. If a loan is transferred from the loan portfolio to the held for sale category, any write-down in the carrying amount of the loan at the date of transfer is recorded as a charge-off against the allowance for loan losses, or ALL. Subsequent declines in fair value are recognized as a charge to noninterest income. When a loan is placed in the held for sale category, we stop amortizing the related deferred fees and costs. The remaining unamortized fees and costs are recognized as part of the cost basis of the loan at the time it is sold. Gains and losses on sales of loans held for sale are included in other noninterest income in the Consolidated Statements of Net Income. Loans Loans are reported at the principal amount outstanding net of unearned income, unamortized premiums or discounts and deferred origination fees and costs. We defer certain nonrefundable loan origination and commitment fees. Accretion of discounts and amortization of premiums on loans are included in interest income in the Consolidated Statements of Net Income. Loan origination fees and direct loan origination costs are deferred and amortized as an adjustment of loan yield over the respective lives of the loans without consideration of anticipated prepayments. If a loan is paid off, the remaining unaccreted or unamortized net origination fees and costs are immediately recognized into income or expense. Interest is accrued and interest income is recognized on loans as earned. Acquired loans are recorded at fair value on the date of acquisition with no carryover of the related ALL. Determining the fair value of the acquired loans involves estimating the principal and interest cash flows expected to be collected on the loans and discounting those cash flows at a market rate of interest. In estimating the fair value of our acquired loans, we consider a number of factors including the loan term, internal risk rating, delinquency status, prepayment rates, recovery periods, estimated value of the underlying collateral and the current interest rate environment. Closed-end installment loans, amortizing loans secured by real estate and any other loans with payments scheduled monthly are reported past due when the borrower is in arrears two or more monthly payments. Other multi-payment obligations with payments scheduled other than monthly are reported past due when one scheduled payment is due and unpaid for 30 days or more. Generally, consumer loans are charged off against the ALL upon the loan reaching 90 days past due. Commercial loans are charged off as management becomes aware of facts and circumstances that raise doubt as to the collectability of all or a portion of the principal and when we believe a confirmed loss exists. Nonaccrual or Nonperforming Loans We stop accruing interest on a loan when the borrower’s payment is 90 days past due. Loans are also placed on nonaccrual status when we have doubt about the borrower’s ability to comply with contractual repayment terms, even if payment is not past due. When the interest accrual is discontinued, all unpaid accrued interest is reversed against interest income. Interest income is recognized on nonaccrual loans on a cash basis if recovery of the remaining principal is reasonably assured. As a general rule, a nonaccrual loan may be restored to accrual status when its principal and interest is paid current and the bank expects repayment of the remaining contractual principal and interest, or when the loan otherwise becomes well secured and in the process of collection. Troubled Debt Restructurings Troubled debt restructurings, or TDRs, are loans where we, for economic or legal reasons related to a borrower’s financial difficulties, grant a concession to the borrower. We strive to identify borrowers with financial difficulty early and work with them to come to a mutual resolution to modify the terms of their loan before the loan reaches nonaccrual status. These modified terms generally include extensions of maturity dates at a stated interest rate lower than the current market rate for a new loan with similar risk characteristics, reductions in contractual interest rates or principal deferment. While unusual, there may be instances of principal forgiveness. These modifications are generally for longer term periods that would not be considered insignificant. Additionally, we classify loans where the debt obligation has been discharged through a Chapter 7 Bankruptcy and not reaffirmed as TDRs. We individually evaluate all substandard commercial loans that have experienced a forbearance or change in terms agreement, and all substandard consumer and residential mortgage loans that entered into an agreement to modify their existing loan, to determine if they should be designated as TDRs. All TDRs are considered to be impaired loans and will be reported as impaired loans for the remaining life of the loan, unless the restructuring agreement specifies an interest rate equal to or greater than the rate that would be accepted at the time of the restructuring for a new loan with comparable risk and it is fully expected that the remaining principal and interest will be collected according to the restructured agreement. Further, all impaired loans are reported as nonaccrual loans unless the loan is a TDR that has met the requirements to be returned to accruing status. TDRs can be returned to accruing status if the ultimate collectability of all contractual amounts due, according to the restructured agreement, is not in doubt and there is a period of a minimum of six months of satisfactory payment performance by the borrower either immediately before or after the restructuring. Allowance for Loan Losses The ALL reflects our estimates of probable losses inherent in the loan portfolio at the balance sheet date. The methodology for determining the ALL has two main components: evaluation and impairment tests of individual loans and evaluation and impairment tests of certain groups of homogeneous loans with similar risk characteristics. Loans are considered to be impaired when based upon current information and events it is probable that we will be unable to collect all principal and interest payments due according to the original contractual terms of the loan agreement. We individually evaluate all substandard and nonaccrual commercial loans greater than $0.5 million for impairment. All TDRs will be reported as an impaired loan for the remaining life of the loan, unless the restructuring agreement specifies an interest rate equal to or greater than the rate that would be accepted at the time of the restructuring for a new loan with comparable risk and it is fully expected that the remaining principal and interest will be fully collected according to the restructured agreement. For all TDRs, regardless of size, and all other impaired loans, we conduct further analysis to determine the probable loss and assign a specific reserve to the loan if deemed appropriate. Specific reserves are established based upon the following three impairment methods: 1) the present value of expected future cash flows discounted at the loan’s original effective interest rate, 2) the loan’s observable market price or 3) the estimated fair value of the collateral if the loan is collateral dependent. Our impairment evaluations consist primarily of the fair value of collateral method because most of our loans are collateral dependent. Collateral values are discounted to consider disposition costs when appropriate. A specific reserve is established or a charge-off is taken if the fair value of the impaired loan is less than the recorded investment in the loan balance. The ALL for homogeneous loans is calculated using a systematic methodology with both a quantitative and a qualitative analysis that is applied on a quarterly basis. The ALL model is comprised of five distinct portfolio segments: 1) Commercial Real Estate, or CRE, 2) Commercial and Industrial, or C&I, 3) Commercial Construction, 4) Consumer Real Estate and 5) Other Consumer. Each segment has a distinct set of risk characteristics monitored by management. We further assess and monitor risk and performance at a more disaggregated level which includes our internal risk rating system for the commercial segments and type of collateral, lien position and loan-to-value, or LTV, for the consumer segments. We first apply historical loss rates to pools of loans with similar risk characteristics. Loss rates are calculated by historical charge-offs that have occurred within each pool of loans over the loss emergence period, or LEP. The LEP is an estimate of the average amount of time from when an event happens that causes the borrower to be unable to pay on a loan until the loss is confirmed through a loan charge-off. In conjunction with our annual review of the ALL assumptions, we have updated our analysis of LEPs for our Commercial and Consumer loan portfolio segments using our loan charge-off history. The analysis showed that the LEP for our Commercial Real Estate, or CRE, and Commercial and Industrial, or C&I portfolios, have shortened and the LEP for our Commercial Construction portfolio segment has lengthened. We estimate the LEP to be 3 years for CRE and 4 years for construction compared to 3.5 years for both in the prior year and 1.25 years for C&I compared to 2.5 years in the prior year. Our analysis showed an LEP for Consumer Real Estate of 2.75 years compared to 3.5 years in the prior year and Other Consumer of 1.25 years which is consistent with the prior year. Another key assumption is the look-back period, or LBP, which represents the historical data period utilized to calculate loss rates. During 2016, we lengthened the LBP for all Commercial and Consumer portfolio segments in order to capture relevant historical data believed to be reflective of losses inherent in the portfolios. We used 7.5 years for our LBP for all portfolio segments which encompasses our loss experience during the recession, and our more recent improved loss experience. This compared to a LBP of 6.5 years in the prior year. The changes made to the ALL assumptions were applied prospectively and did not result in a material change to the total ALL. After consideration of the historic loss calculations, management applies additional qualitative adjustments so that the ALL is reflective of the inherent losses that exist in the loan portfolio at the balance sheet date. Qualitative adjustments are made based upon changes in lending policies and practices, economic conditions, changes in the loan portfolio, changes in lending management, results of internal loan reviews, asset quality trends, collateral values, concentrations of credit risk and other external factors. The evaluation of the various components of the ALL requires considerable judgment in order to estimate inherent loss exposures. Acquired loans are recorded at fair value on the date of acquisition with no carryover of the related ALL. Determining the fair value of acquired loans involves estimating the principal and interest cash flows expected to be collected on the loans and discounting those cash flows at a market rate of interest. In estimating the fair value of our acquired loans, we considered a number of factors including the loan term, internal risk rating, delinquency status, prepayment rates, recovery periods, estimated value of the underlying collateral and the current interest rate environment. Loans acquired with evidence of credit deterioration were evaluated and not considered to be significant. The premium or discount estimated through the loan fair value calculation is recognized into interest income on a level yield or straight-line basis over the remaining contractual life of the loans. Additional credit deterioration on acquired loans, in excess of the original credit discount embedded in the fair value determination on the date of acquisition, will be recognized in the ALL through the provision for loan losses. Our ALL Committee meets quarterly to verify the overall adequacy of the ALL. Additionally, on an annual basis, the ALL Committee meets to validate our ALL methodology. This validation includes reviewing the loan segmentation, LEP, LBP and the qualitative framework. As a result of this ongoing monitoring process, we may make changes to our ALL to be responsive to the economic environment. Although we believe our process for determining the ALL adequately considers all of the factors that would likely result in credit losses, the process includes subjective elements and may be susceptible to significant change. To the extent actual losses are higher than management estimates, additional provisions for loan losses could be required and could adversely affect our earnings or financial position in future periods.

Business Combinations

Business Combinations	12 Months Ended
	Dec. 31, 2016
Business Combinations [Abstract]
Business Combinations	BUSINESS COMBINATIONS On March 4, 2015, we acquired 100 percent of the voting shares of Integrity Bancshares, Inc., or Integrity, located in Camp Hill, Pennsylvania, through a tax-free reorganization transaction structured as a merger of Integrity with and into S&T, with S&T being the surviving entity. As a result of the Integrity merger, or the Merger, Integrity Bank, the wholly owned subsidiary bank of Integrity, became a separate wholly owned subsidiary bank of S&T. The merger of Integrity Bank into S&T Bank, with S&T Bank surviving the merger, and related system conversion occurred on May 8, 2015. Integrity shareholders were entitled to elect to receive for each share of Integrity common stock either $52.50 in cash or 2.0627 shares of S&T common stock subject to allocation and proration procedures in the merger agreement. The total purchase price was approximately $172.0 million which included $29.5 million of cash and 4,933,115 S&T common shares at a fair value of $28.88 per share. The fair value of $28.88 per share of S&T common stock was based on the March 4, 2015 closing price. The Merger was accounted for under the acquisition method of accounting and our Consolidated Financial Statements include all Integrity Bank transactions from March 4, 2015, until it was merged into S&T Bank on May 8, 2015. The assets acquired and liabilities assumed were recorded at their respective fair values and represent management’s estimates based on available information. Purchase accounting guidance allows for a reasonable period of time following an acquisition for the acquirer to obtain the information necessary to complete the accounting for a business combination. This period is known as the measurement period. At the end of the measurement period, $1.1 million in purchase accounting adjustments were recognized that increased goodwill. The measurement period adjustments primarily related to changes to provisional amounts, a $0.8 million reduction in the fair value of land and $0.3 million to deferred taxes. Goodwill of $115.9 million was calculated as the excess of the consideration exchanged over the fair value of the identifiable net assets acquired. The goodwill arising from the Merger consists largely of the synergies and economies of scale expected from combining the operations of S&T and Integrity. All of the goodwill was assigned to our Community Banking segment. The goodwill recognized will not be deductible for tax purposes. The following table summarizes total consideration, assets acquired and liabilities assumed from the Merger: (dollars in thousands) Consideration Paid Cash $ 29,510 Common stock 142,469 Fair Value of Total Consideration $ 171,979 Fair Value of Assets Acquired Cash and cash equivalents $ 13,163 Securities and other investments 11,502 Loans 788,687 Bank owned life insurance 15,974 Premises and equipment 10,855 Core deposit intangible 5,713 Other assets 19,088 Total Assets Acquired 864,982 Fair Value of Liabilities Assumed Deposits 722,308 Borrowings 82,286 Other liabilities 4,259 Total Liabilities Assumed 808,853 Total Fair Value of Identifiable Net Assets 56,129 Goodwill $ 115,850 Loans acquired in the Merger were recorded at fair value with no carryover of the related Allowance for Loan Losses, or ALL. Determining the fair value of the loans involves estimating the amount and timing of principal and interest cash flows expected to be collected on the loans and discounting those cash flows at a market rate of interest. The fair value of the loans acquired was $788.7 million net of a $14.8 million discount. The discount is accreted to interest income over the remaining contractual life of the loans. At March 4, 2015, acquired loans included $331.6 million of CRE, $184.2 million of C&I, $92.4 million of commercial construction, $116.9 million of residential mortgage, $25.6 million of home equity, $36.1 million of installment and other consumer and $1.9 million of consumer construction. Direct costs related to the Merger were expensed as incurred. No Merger related expenses were recognized during 2016. During 2015, we recognized $3.2 million of Merger related expenses, including $1.3 million for data processing contract termination and system conversion costs, $1.2 million in legal and professional expenses, $0.4 million in severance payments and $0.3 million in other expenses.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2016
Earnings Per Share [Abstract]
Earnings Per Share	EARNINGS PER SHARE The following table reconciles the numerators and denominators of basic and diluted EPS: Years ended December 31, (dollars in thousands, except share and per share data) 2016 2015 2014 Numerator for Earnings per Common Share—Basic: Net income $ 71,392 $ 67,081 $ 57,910 Less: Income allocated to participating shares 225 280 165 Net Income Allocated to Common Shareholders $ 71,167 $ 66,801 $ 57,745 Numerator for Earnings per Common Share—Diluted: Net income $ 71,392 $ 67,081 $ 57,910 Denominators: Weighted Average Common Shares Outstanding—Basic 34,677,738 33,812,990 29,683,103 Add: Dilutive potential common shares 95,432 35,092 25,621 Denominator for Treasury Stock Method—Diluted 34,773,170 33,848,082 29,708,724 Weighted Average Common Shares Outstanding—Basic 34,677,738 33,812,990 29,683,103 Add: Average participating shares outstanding 109,755 141,558 84,918 Denominator for Two-Class Method—Diluted 34,787,493 33,954,548 29,768,021 Earnings per common share—basic $ 2.06 $ 1.98 $ 1.95 Earnings per common share—diluted $ 2.05 $ 1.98 $ 1.95 Warrants considered anti-dilutive excluded from dilutive potential common shares - exercise price $31.53 per share, expires January 2019 517,012 517,012 517,012 Stock options considered anti-dilutive excluded from dilutive potential common shares — — 419,538 Restricted stock considered anti-dilutive excluded from dilutive potential common shares 116,749 106,466 59,297

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	FAIR VALUE MEASUREMENTS The following tables present our assets and liabilities that are measured at fair value on a recurring basis by fair value hierarchy level at December 31, 2016 and 2015. December 31, 2016 (dollars in thousands) Level 1 Level 2 Level 3 Total ASSETS Securities available-for-sale: U.S. Treasury securities $ — $ 24,811 $ — $ 24,811 Obligations of U.S. government corporations and agencies — 232,179 — 232,179 Collateralized mortgage obligations of U.S. government corporations and agencies — 129,777 — 129,777 Residential mortgage-backed securities of U.S. government corporations and agencies — 37,358 — 37,358 Commercial mortgage-backed securities of U.S. government corporations and agencies — 125,604 — 125,604 Obligations of states and political subdivisions — 132,509 — 132,509 Marketable equity securities — 11,249 — 11,249 Total securities available-for-sale — 693,487 — 693,487 Trading securities held in a Rabbi Trust 4,410 — — 4,410 Total securities 4,410 693,487 — 697,897 Derivative financial assets: Interest rate swaps — 6,960 — 6,960 Interest rate lock commitments — 236 — 236 Total Assets $ 4,410 $ 700,683 $ — $ 705,093 LIABILITIES Derivative financial liabilities: Interest rate swaps $ — $ 6,958 $ — $ 6,958 Forward sale contracts — 27 — 27 Total Liabilities $ — $ 6,985 $ — $ 6,985 December 31, 2015 (dollars in thousands) Level 1 Level 2 Level 3 Total ASSETS Securities available-for-sale: U.S. Treasury securities $ — $ 14,941 $ — $ 14,941 Obligations of U.S. government corporations and agencies — 263,303 — 263,303 Collateralized mortgage obligations of U.S. government corporations and agencies — 128,835 — 128,835 Residential mortgage-backed securities of U.S. government corporations and agencies — 40,125 — 40,125 Commercial mortgage-backed securities of U.S. government corporations and agencies — 69,204 — 69,204 Obligations of states and political subdivisions — 134,886 — 134,886 Marketable equity securities — 9,669 — 9,669 Total securities available-for-sale 660,963 — 660,963 Trading securities held in a Rabbi Trust 4,021 — — 4,021 Total securities 4,021 660,963 — 664,984 Derivative financial assets: Interest rate swaps — 11,295 — 11,295 Interest rate lock commitments — 261 — 261 Total Assets $ 4,021 $ 672,519 $ — $ 676,540 LIABILITIES Derivative financial liabilities: Interest rate swaps $ — $ 11,276 $ — $ 11,276 Forward Sale Contracts — 5 — 5 Total Liabilities $ — $ 11,281 $ — $ 11,281 We classify financial instruments as Level 3 when valuation models are used because significant inputs are not observable in the market. We may be required to measure certain assets and liabilities at fair value on a nonrecurring basis. Nonrecurring assets are recorded at the lower of cost or fair value in our financial statements. There were no liabilities measured at fair value on a nonrecurring basis at either December 31, 2016 or December 31, 2015. The following table presents our assets that are measured at fair value on a nonrecurring basis by the fair value hierarchy level as of the dates presented: December 31, 2016 December 31, 2015 (dollars in thousands) Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total ASSETS (1) Loans held for sale $ — $ — $ 1,802 $ 1,802 $ — $ — $ — $ — Impaired loans — — 10,329 10,329 — — 9,373 9,373 Other real estate owned — — 396 396 — — 158 158 Mortgage servicing rights — — 4,098 4,098 — — 3,396 3,396 Total Assets $ — $ — $ 16,625 $ 16,625 $ — $ — $ 12,927 $ 12,927 (1) This table presents only the nonrecurring items that are recorded at fair value in our financial statements. The carrying values and fair values of our financial instruments at December 31, 2016 and 2015 are presented in the following tables: Fair Value Measurements at December 31, 2016 (dollars in thousands) Carrying Value (1) Total Level 1 Level 2 Level 3 ASSETS Cash and due from banks, including interest-bearing deposits $ 139,486 $ 139,486 $ 139,486 $ — $ — Securities available-for-sale 693,487 693,487 — 693,487 — Loans held for sale 3,793 3,815 — — 3,815 Portfolio loans, net of unearned income 5,611,419 5,551,266 — — 5,551,266 Bank owned life insurance 72,081 72,081 — 72,081 — FHLB and other restricted stock 31,817 31,817 — — 31,817 Trading securities held in a Rabbi Trust 4,410 4,410 4,410 — — Mortgage servicing rights 3,744 4,098 — — 4,098 Interest rate swaps 6,960 6,960 — 6,960 — Interest rate lock commitments 236 236 — 236 — LIABILITIES Deposits $ 5,272,377 $ 5,276,499 $ — $ — $ 5,276,499 Securities sold under repurchase agreements 50,832 50,832 — — 50,832 Short-term borrowings 660,000 660,000 — — 660,000 Long-term borrowings 14,713 15,267 — — 15,267 Junior subordinated debt securities 45,619 45,619 — — 45,619 Interest rate swaps 6,958 6,958 — 6,958 — Forward sale contracts 27 27 — 27 — (1) As reported in the Consolidated Balance Sheets Fair Value Measurements at December 31, 2015 (dollars in thousands) Carrying Value (1) Total Level 1 Level 2 Level 3 ASSETS Cash and due from banks, including interest-bearing deposits $ 99,399 $ 99,399 $ 99,399 $ — $ — Securities available-for-sale 660,963 660,963 — 660,963 — Loans held for sale 35,321 35,500 — — 35,500 Portfolio loans, net of unearned income 5,027,612 5,001,004 — — 5,001,004 Bank owned life insurance 70,175 70,175 — 70,175 — FHLB and other restricted stock 23,032 23,032 — — 23,032 Trading securities held in a Rabbi Trust 4,021 4,021 4,021 — — Mortgage servicing rights 3,237 3,396 — — 3,396 Interest rate swaps 11,295 11,295 — 11,295 — Interest rate lock commitments 261 261 — 261 — LIABILITIES Deposits $ 4,876,611 $ 4,881,718 $ — $ — $ 4,881,718 Securities sold under repurchase agreements 62,086 62,086 — — 62,086 Short-term borrowings 356,000 356,000 — — 356,000 Long-term borrowings 117,043 117,859 — — 117,859 Junior subordinated debt securities 45,619 45,619 — — 45,619 Interest rate swaps 11,276 11,276 — 11,276 — Forward sale contracts 5 5 — 5 — (1) As reported in the Consolidated Balance Sheets

Restrictions on Cash and Due fr

Restrictions on Cash and Due from Bank Accounts	12 Months Ended
	Dec. 31, 2016
Cash and Cash Equivalents [Abstract]
Restrictions on Cash and Due from Bank Accounts	RESTRICTIONS ON CASH AND DUE FROM BANK ACCOUNTS The Board of Governors of the Federal Reserve System, or the Federal Reserve, imposes certain reserve requirements on all depository institutions. These reserves are maintained in the form of vault cash or as an interest-bearing balance with the Federal Reserve. The required reserves averaged $36.8 million for 2016, $44.1 million for 2015 and $41.8 million for 2014.

Dividend and Loan Restrictions

Dividend and Loan Restrictions	12 Months Ended
	Dec. 31, 2016
Equity [Abstract]
Dividend and Loan Restrictions	DIVIDEND AND LOAN RESTRICTIONS S&T is a legal entity separate and distinct from its banking and other subsidiaries. A substantial portion of our revenues consist of dividend payments we receive from S&T Bank. S&T Bank, in turn, is subject to state laws and regulations that limit the amount of dividends it can pay to us. In addition, both S&T and S&T Bank are subject to various general regulatory policies relating to the payment of dividends, including requirements to maintain adequate capital above regulatory minimums. The Federal Reserve has indicated that banking organizations should generally pay dividends only if (i) the organization’s net income available to common shareholders over the past year has been sufficient to fully fund the dividends and (ii) the prospective rate of earnings retention appears consistent with the organization’s capital needs, asset quality and overall financial condition. Thus, under certain circumstances based upon our financial condition, our ability to declare and pay quarterly dividends may require consultation with the Federal Reserve and may be prohibited by applicable Federal Reserve guidelines. Federal law prohibits us from borrowing from S&T Bank unless such loans are collateralized by specific obligations. Further, such loans are limited to 10 percent of S&T Bank’s capital stock and surplus.

Securities Available-for-Sale

Securities Available-for-Sale	12 Months Ended
	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Securities Available-for-Sale	SECURITIES AVAILABLE-FOR-SALE The following tables present the amortized cost and fair value of available-for-sale securities as of the dates presented: December 31, 2016 December 31, 2015 (dollars in thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S. Treasury securities $ 24,891 $ 47 $ (127 ) $ 24,811 $ 14,914 $ 27 $ — $ 14,941 Obligations of U.S. government corporations and agencies 230,989 1,573 (383 ) 232,179 262,045 1,825 (567 ) 263,303 Collateralized mortgage obligations of U.S. government corporations and agencies 130,046 465 (734 ) 129,777 128,458 693 (316 ) 128,835 Residential mortgage-backed securities of U.S. government corporations and agencies 36,606 984 (232 ) 37,358 39,185 1,091 (151 ) 40,125 Commercial mortgage-backed securities of U.S. government corporations and agencies 127,311 243 (1,950 ) 125,604 69,697 183 (676 ) 69,204 Obligations of states and political subdivisions 128,783 3,772 (46 ) 132,509 128,904 5,988 (6 ) 134,886 Debt Securities 678,626 7,084 (3,472 ) 682,238 643,203 9,807 (1,716 ) 651,294 Marketable equity securities 7,579 3,670 — 11,249 7,579 2,090 — 9,669 Total $ 686,205 $ 10,754 $ (3,472 ) $ 693,487 $ 650,782 $ 11,897 $ (1,716 ) $ 660,963 The following table shows the composition of gross and net realized gains and losses for the periods presented: Years ended December 31, (dollars in thousands) 2016 2015 2014 Gross realized gains $ — $ — $ 41 Gross realized losses — (34 ) — Net Realized (Losses) Gains $ — $ (34 ) $ 41 The following tables present the fair value and the age of gross unrealized losses by investment category as of the dates presented: December 31, 2016 Less Than 12 Months 12 Months or More Total (dollars in thousands) Number of Securities Fair Unrealized Losses Number of Securities Fair Unrealized Losses Number of Securities Fair Unrealized Losses U.S. Treasury securities 1 $ 9,811 $ (127 ) — $ — $ — 1 $ 9,811 $ (127 ) Obligations of U.S. government corporations and agencies 7 62,483 (383 ) — — — 7 62,483 (383 ) Collateralized mortgage obligations of U.S. government corporations and agencies 10 83,031 (734 ) — — — 10 83,031 (734 ) Residential mortgage-backed securities of U.S. government corporations and agencies 2 10,022 (232 ) — — — 2 10,022 (232 ) Commercial mortgage-backed securities of U.S. government corporations and agencies 10 96,576 (1,950 ) — — — 10 96,576 (1,950 ) Obligations of states and political subdivisions 1 5,577 (46 ) — — — 1 5,577 (46 ) Debt Securities 31 267,500 (3,472 ) — — — 31 267,500 (3,472 ) Marketable equity securities — — — — — — — — — Total Temporarily Impaired Securities 31 $ 267,500 $ (3,472 ) — $ — $ — 31 $ 267,500 $ (3,472 ) December 31, 2015 Less Than 12 Months 12 Months or More Total (dollars in thousands) Number of Securities Fair Value Unrealized Losses Number of Securities Fair Value Unrealized Losses Number of Securities Fair Value Unrealized Losses U.S. Treasury securities — $ — $ — — $ — $ — — $ — $ — Obligations of U.S. government corporations and agencies 10 88,584 (379 ) 2 14,542 (188 ) 12 103,126 (567 ) Collateralized mortgage obligations of U.S. government corporations and agencies 6 61,211 (316 ) — — — 6 61,211 (316 ) Residential mortgage-backed securities of U.S. government corporations and agencies 1 7,993 (151 ) — — — 1 7,993 (151 ) Commercial mortgage-backed securities of U.S. government corporations and agencies 5 50,839 (450 ) 1 9,472 (226 ) 6 60,311 (676 ) Obligations of states and political subdivisions 1 5,370 (6 ) — — — 1 5,370 (6 ) Debt Securities 23 213,997 (1,302 ) 3 24,014 (414 ) 26 238,011 (1,716 ) Marketable equity securities — — — — — — — — — Total Temporarily Impaired Securities 23 $ 213,997 $ (1,302 ) 3 $ 24,014 $ (414 ) 26 $ 238,011 $ (1,716 ) We do not believe any individual unrealized loss as of December 31, 2016 represents an other than temporary impairment, or OTTI. As of December 31, 2016, the unrealized losses on 31 debt securities were primarily attributable to changes in interest rates and not related to the credit quality of these securities. All debt securities are determined to be investment grade and are paying principal and interest according to the contractual terms of the security. There were no unrealized losses on marketable equity securities at December 31, 2016 or 2015. We do not intend to sell and it is more likely than not that we will not be required to sell any of the securities in an unrealized loss position before recovery of their amortized cost. The following table displays net unrealized gains and losses, net of tax, on securities available-for-sale included in accumulated other comprehensive income/(loss), for the periods presented: December 31, 2016 December 31, 2015 (dollars in thousands) Gross Unrealized Gains Gross Unrealized Losses Net Unrealized Gains (Losses) Gross Unrealized Gains Gross Unrealized Losses Net Unrealized Gains (Losses) Total unrealized gains (losses) on securities available for sale $ 10,754 $ (3,472 ) $ 7,282 $ 11,897 $ (1,716 ) $ 10,181 Income tax (expense) benefit (3,776 ) 1,219 (2,557 ) (4,164 ) 601 (3,563 ) Net unrealized gains (losses), net of tax included in accumulated other comprehensive income(loss) $ 6,978 $ (2,253 ) $ 4,725 $ 7,733 $ (1,115 ) $ 6,618 The amortized cost and fair value of securities available-for-sale at December 31, 2016 by contractual maturity are included in the table below. Actual maturities may differ from contractual maturities because issuers may have the right to call or prepay obligations with or without call or prepayment penalties. December 31, 2016 (dollars in thousands) Amortized Cost Fair Value Due in one year or less $ 52,594 $ 52,696 Due after one year through five years 201,450 203,513 Due after five years through ten years 64,569 64,975 Due after ten years 66,050 68,315 384,663 389,499 Collateralized mortgage obligations of U.S. government corporations and agencies 130,046 129,777 Residential mortgage-backed securities of U.S. government corporations and agencies 36,606 37,358 Commercial mortgage-backed securities of U.S. government corporations and agencies 127,311 125,604 Debt Securities 678,626 682,238 Marketable equity securities 7,579 11,249 Total $ 686,205 $ 693,487 At December 31, 2016 and 2015, securities with carrying values of $342.0 million and $278.4 million were pledged for various regulatory and legal requirements.

Loans and Loans Held for Sale

Loans and Loans Held for Sale	12 Months Ended
	Dec. 31, 2016
Receivables [Abstract]
Loans and Loans Held for Sale	LOANS AND LOANS HELD FOR SALE Loans are presented net of unearned income of $5.2 million and $3.2 million at December 31, 2016 and 2015 and net of a discount related to purchase accounting fair value adjustments of $7.1 million and $10.9 million at December 31, 2016 and December 31, 2015. The following table indicates the composition of the acquired and originated loans as of the dates presented: December 31, (dollars in thousands) 2016 2015 Commercial Commercial real estate $ 2,498,476 $ 2,166,603 Commercial and industrial 1,401,035 1,256,830 Commercial construction 455,884 413,444 Total Commercial Loans 4,355,395 3,836,877 Consumer Residential mortgage 701,982 639,372 Home equity 482,284 470,845 Installment and other consumer 65,852 73,939 Consumer construction 5,906 6,579 Total Consumer Loans 1,256,024 1,190,735 Total Portfolio Loans 5,611,419 5,027,612 Loans held for sale 3,793 35,321 Total Loans $ 5,615,212 $ 5,062,933 As of December 31, 2016, our acquired loans from the Merger were $543.3 million including $273.0 million of CRE, $140.8 million of C&I, $33.5 million of commercial construction, $74.0 million of residential mortgage and $22.0 million of home equity, installment and other consumer construction. These acquired loans decreased from acquired loans at December 31, 2015 of $673.3 million , including $293.2 million of CRE, $167.7 million of C&I, $69.2 million of commercial construction, $115.6 million of residential mortgage, $27.5 million of home equity, installment and other consumer construction. We attempt to limit our exposure to credit risk by diversifying our loan portfolio by segment, geography, collateral and industry and actively managing concentrations. When concentrations exist in certain segments, we mitigate this risk by reviewing the relevant economic indicators and internal risk rating trends and through stress testing of the loans in these segments. Total commercial loans represented 78 percent of total portfolio loans at December 31, 2016 and 76 percent of total portfolio loans at December 31, 2015. Within our commercial portfolio, the CRE and Commercial Construction portfolios combined comprised $3.0 billion or 68 percent of total commercial loans and 53 percent of total portfolio loans at December 31, 2016 and comprised of $2.6 billion or 67 percent of total commercial loans and 51 percent of total portfolio loans at December 31, 2015. Further segmentation of the CRE and Commercial Construction portfolios by collateral type reveals no concentration in excess of seven percent of total loans at either December 31, 2016 or December 31, 2015. Our market area includes Pennsylvania and the contiguous states of Ohio, West Virginia, New York and Maryland. The majority of our commercial and consumer loans are made to businesses and individuals in this market area, resulting in a geographic concentration. We believe our knowledge and familiarity with customers and conditions locally outweighs this geographic concentration risk. The conditions of the local and regional economies are monitored closely through publicly available data and information supplied by our customers. Our CRE and Commercial Construction portfolios have out-of-market exposure of 5.2 percent of the combined portfolio and 2.7 percent of total portfolio loans at December 31, 2016 and 5.8 percent of the combined portfolio and 3.0 percent of total portfolio loans at December 31, 2015. The decrease in loans held for sale of $31.5 million from December 31, 2015 primarily related to the sale of our credit card portfolio in the first quarter of 2016, which was sold for $25.0 million and resulted in a $2.1 million gain in 2016. The remaining balance related to mortgages held for sale. The following table summarizes the restructured loans as of the dates presented: December 31, 2016 December 31, 2015 (dollars in thousands) Performing TDRs Nonperforming TDRs Total TDRs Performing TDRs Nonperforming TDRs Total TDRs Commercial real estate $ 2,994 $ 646 $ 3,640 $ 6,822 $ 3,548 $ 10,370 Commercial and industrial 1,387 4,493 5,880 6,321 1,570 7,891 Commercial construction 2,966 430 3,396 5,013 1,265 6,278 Residential mortgage 2,375 5,068 7,443 2,590 665 3,255 Home equity 3,683 954 4,637 3,184 523 3,707 Installment and other consumer 18 7 25 25 88 113 Total $ 13,423 $ 11,598 $ 25,021 $ 23,955 $ 7,659 $ 31,614 The following tables present the restructured loans for the 12 months ended December 31: 2016 (dollars in thousands) Number of Loans Pre-Modification Outstanding Recorded Investment (1) Post-Modification Outstanding Recorded Investment (1) Total Difference in Recorded Investment Commercial real estate Interest Rate Reduction 1 $ 250 $ 242 $ (8 ) Chapter 7 bankruptcy (2) 1 709 646 (63 ) Commercial and industrial Principal deferral 5 985 986 1 Maturity date extension 4 4,756 3,334 (1,422 ) Commercial construction Maturity date extension 3 1,251 1,151 (100 ) Residential mortgage Principal deferral 1 3,273 3,133 (140 ) Maturity date extension 1 483 414 (69 ) Maturity date extension and interest rate reduction 1 280 279 (1 ) Chapter 7 bankruptcy (2) 7 439 413 (26 ) Home equity Maturity date extension 5 305 298 (7 ) Maturity date extension and interest rate reduction 2 604 598 (6 ) Principal deferral 1 47 45 (2 ) Chapter 7 bankruptcy (2) 19 676 643 (33 ) Installment and other consumer Chapter 7 bankruptcy (2) 2 16 10 (6 ) Total by Concession Type Principal deferral 7 4,305 4,164 (141 ) Interest rate reduction 1 250 242 (8 ) Maturity date extension and interest rate reduction 3 884 877 (7 ) Maturity date extension 13 6,795 5,197 (1,598 ) Chapter 7 bankruptcy (2) 29 1,840 1,712 (128 ) Total 53 $ 14,074 $ 12,192 $ (1,882 ) (1) Excludes loans that were fully paid off or fully charged-off by period end. The pre-modification balance represents the balance outstanding prior to modification. The post-modification balance represents the outstanding balance at period end. (2) Chapter 7 bankruptcy loans where the debt has been legally discharged through the bankruptcy court and not reaffirmed. 2015 (dollars in thousands) Number of Loans Pre-Modification Outstanding Recorded Investment ( 1) Post-Modification Outstanding Recorded Investment (1 ) Total Difference in Recorded Investment Commercial real estate Principal deferral 2 $ 2,851 $ 1,841 $ (1,010 ) Maturity date extension 3 438 427 (11 ) Commercial and industrial Principal deferral 6 661 363 (298 ) Maturity date extension 2 824 728 (96 ) Commercial construction Maturity date extension 3 1,434 1,432 (2 ) Residential mortgage Maturity date extension 8 545 265 (280 ) Maturity date extension and interest rate reduction 1 207 205 (2 ) Chapter 7 bankruptcy (2) 7 428 226 (202 ) Home Equity Maturity date extension and interest rate reduction 3 203 201 (2 ) Maturity date extension 1 71 70 (1 ) Chapter 7 bankruptcy (2) 23 619 576 (43 ) Installment and other consumer Chapter 7 bankruptcy (2) 1 9 4 (5 ) Total by Concession Type Principal deferral 8 3,512 2,204 (1,308 ) Maturity date extension and interest rate reduction 4 410 406 (4 ) Maturity date extension 17 3,312 2,922 (390 ) Chapter 7 bankruptcy (2) 31 1,056 806 (250 ) Total 60 $ 8,290 $ 6,338 $ (1,952 ) (1) Excludes loans that were fully paid off or fully charged-off by period end. The pre-modification balance represents the balance outstanding prior to modification. The post-modification balance represents the outstanding balance at period end. (2) Chapter 7 bankruptcy loans where the debt has been legally discharged through the bankruptcy court and not reaffirmed. During 2016, we modified 18 loans that were not considered to be TDRs, including 15 C&I loans for $25.6 million , and three CRE loans for $3.1 million . The modifications primarily represented instances where we were adequately compensated through additional collateral or a higher interest rate or there was an insignificant delay in payment. As of December 31, 2016, we have one commitment for $0.8 million to lend additional funds on any TDRs. We returned five TDRs totaling $0.9 million to accruing status during 2016. We returned eight TDRs to accruing status during 2015 totaling $0.4 million . Defaulted TDRs are defined as loans having a payment default of 90 days or more after the restructuring takes place. There were no TDRs that defaulted during the years ended December 31, 2016 and 2015 that were restructured within the last 12 months prior to defaulting. The following table is a summary of nonperforming assets as of the dates presented: December 31, (dollars in thousands) 2016 2015 Nonperforming Assets Nonaccrual loans $ 31,037 $ 27,723 Nonaccrual TDRs 11,598 7,659 Total nonaccrual loans 42,635 35,382 OREO 679 354 Total Nonperforming Assets $ 43,314 $ 35,736 NPAs increased $7.6 million to $43.3 million during 2016 compared to $35.7 million for the year ended 2015, primarily due to subsequent deterioration on acquired loans since the acquisition date of $16.9 million offset by loan payoffs and charge-offs. We have granted loans to certain officers and directors of S&T and to certain affiliates of the officers and directors in the ordinary course of business. These loans were made on substantially the same terms, including interest rates and collateral, as those prevailing at the time for comparable transactions with unrelated persons and did not involve more than normal risk of collectability. The following table presents a summary of the aggregate amount of loans to any such persons as of December 31: (dollars in thousands) 2016 2015 Balance at beginning of year $ 24,517 $ 27,368 New loans 22,740 24,743 Repayments (22,090 ) (27,594 ) Balance at End of Year $ 25,167 $ 24,517

Allowance for Loan Losses

Allowance for Loan Losses	12 Months Ended
	Dec. 31, 2016
Receivables [Abstract]
Allowance for Loan Losses	ALLOWANCE FOR LOAN LOSSES We maintain an ALL at a level determined to be adequate to absorb estimated probable credit losses inherent in the loan portfolio as of the balance sheet date. We develop and document a systematic ALL methodology based on the following portfolio segments: 1) CRE, 2) C&I, 3) Commercial Construction, 4) Consumer Real Estate and 5) Other Consumer. The following are key risks within each portfolio segment: CRE —Loans secured by commercial purpose real estate, including both owner occupied properties and investment properties for various purposes such as hotels, strip malls and apartments. Operations of the individual projects and global cash flows of the debtors are the primary sources of repayment for these loans. The condition of the local economy is an important indicator of risk, but there are also more specific risks depending on the collateral type and the business prospects of the lessee, if the project is not owner occupied. C&I —Loans made to operating companies or manufacturers for the purpose of production, operating capacity, accounts receivable, inventory or equipment financing. Cash flow from the operations of the company is the primary source of repayment for these loans. The condition of the local economy is an important indicator of risk, but there are also more specific risks depending on the industry of the company. Collateral for these types of loans often do not have sufficient value in a distressed or liquidation scenario to satisfy the outstanding debt. Commercial Construction —Loans made to finance construction of buildings or other structures, as well as to finance the acquisition and development of raw land for various purposes. While the risk of these loans is generally confined to the construction period, if there are problems, the project may not be completed, and as such, may not provide sufficient cash flow on its own to service the debt or have sufficient value in a liquidation to cover the outstanding principal. The condition of the local economy is an important indicator of risk, but there are also more specific risks depending on the type of project and the experience and resources of the developer. Consumer Real Estate —Loans secured by first and second liens such as home equity loans, home equity lines of credit and 1-4 family residential mortgages, including purchase money mortgages. The primary source of repayment for these loans is the income and assets of the borrower. The condition of the local economy, in particular the unemployment rate, is an important indicator of risk for this segment. The state of the local housing market can also have a significant impact on this segment because low demand and/or declining home values can limit the ability of borrowers to sell a property and satisfy the debt. Other Consumer —Loans made to individuals that may be secured by assets other than 1-4 family residences, as well as unsecured loans. This segment includes auto loans, unsecured loans and lines and credit cards. The primary source of repayment for these loans is the income and assets of the borrower. The condition of the local economy, in particular the unemployment rate, is an important indicator of risk for this segment. The value of the collateral, if there is any, is less likely to be a source of repayment due to less certain collateral values. We further assess risk within each portfolio segment by pooling loans with similar risk characteristics. For the commercial loan classes, the most important indicator of risk is the internally assigned risk rating, including pass, special mention and substandard. Consumer loans are pooled by type of collateral, lien position and loan to value, or LTV, ratio for Consumer Real Estate loans. Historical loss rates are applied to these loan pools to determine the reserve for loans collectively evaluated for impairment. The ALL methodology for groups of loans collectively evaluated for impairment is comprised of both a quantitative and qualitative analysis. A key assumption in the quantitative component of the reserve is the loss emergence period, or LEP. The LEP is an estimate of the average amount of time from the point at which a loss is incurred on a loan to the point at which the loss is confirmed. Another key assumption is the look-back period, or LBP, which represents the historical data period utilized to calculate loss rates. Management monitors various credit quality indicators for both the commercial and consumer loan portfolios, including delinquency, nonperforming status and changes in risk ratings on a monthly basis. The following tables present the age analysis of past due loans segregated by class of loans as of the dates presented: December 31, 2016 (dollars in thousands) Current 30-59 Days Past Due 60-89 Days Past Due Non- performing Total Past Due Loans Total Loans Commercial real estate $ 2,479,513 $ 2,032 $ 759 $ 16,172 $ 18,963 $ 2,498,476 Commercial and industrial 1,391,475 1,061 428 8,071 9,560 1,401,035 Commercial construction 450,410 547 — 4,927 5,474 455,884 Residential mortgage 689,635 1,312 1,117 9,918 12,347 701,982 Home equity 476,866 1,470 509 3,439 5,418 482,284 Installment and other consumer 65,525 176 43 108 327 65,852 Consumer construction 5,906 — — — — 5,906 Loans held for sale 3,793 — — — — 3,793 Total $ 5,563,123 $ 6,598 $ 2,856 $ 42,635 $ 52,089 $ 5,615,212 December 31, 2015 (dollars in thousands) Current 30-59 Days Past Due 60-89 Days Past Due Non- performing Total Past Due Loans Total Loans Commercial real estate $ 2,145,655 $ 11,602 $ 627 $ 8,719 $ 20,948 $ 2,166,603 Commercial and industrial 1,244,802 2,453 296 9,279 12,028 1,256,830 Commercial construction 401,084 3,517 90 8,753 12,360 413,444 Residential mortgage 631,085 1,728 930 5,629 8,287 639,372 Home equity 465,055 2,365 523 2,902 5,790 470,845 Installment and other consumer 73,486 242 111 100 453 73,939 Consumer construction 6,579 — — — — 6,579 Loans held for sale 35,179 94 48 — 142 35,321 Total $ 5,002,925 $ 22,001 $ 2,625 $ 35,382 $ 60,008 $ 5,062,933 We continually monitor the commercial loan portfolio through an internal risk rating system. Loan risk ratings are assigned based upon the creditworthiness of the borrower and are reviewed on an ongoing basis according to our internal policies. Loans within the pass rating generally have a lower risk of loss than loans risk rated as special mention and substandard. Our risk ratings are consistent with regulatory guidance and are as follows: Pass —The loan is currently performing and is of high quality. Special Mention —A special mention loan has potential weaknesses that warrant management’s close attention. If left uncorrected, these potential weaknesses may result in deterioration of the repayment prospects or in the strength of our credit position at some future date. Economic and market conditions, beyond the borrower’s control, may in the future necessitate this classification. Substandard —A substandard loan is not adequately protected by the net worth and/or paying capacity of the borrower or by the collateral pledged, if any. Substandard loans have a well-defined weakness or weaknesses that jeopardize the liquidation of the debt. These loans are characterized by the distinct possibility that we will sustain some loss if the deficiencies are not corrected. The following tables present the recorded investment in commercial loan classes by internally assigned risk ratings as of the dates presented: December 31, 2016 (dollars in thousands) Commercial Real Estate % of Total Commercial and Industrial % of Total Commercial Construction % of Total Total % of Total Pass $ 2,423,742 97.0 % $ 1,315,507 93.9 % $ 430,472 94.4 % $ 4,169,721 95.7 % Special mention 33,098 1.3 % 40,409 2.9 % 14,691 3.2 % 88,198 2.0 % Substandard 41,636 1.7 % 45,119 3.2 % 10,721 2.4 % 97,476 2.3 % Total $ 2,498,476 100.0 % $ 1,401,035 100.0 % $ 455,884 100.0 % $ 4,355,395 100.0 % December 31, 2015 (dollars in thousands) Commercial Real Estate % of Total Commercial and Industrial % of Total Commercial Construction % of Total Total % of Total Pass $ 2,094,851 96.7 % $ 1,182,685 94.1 % $ 375,808 90.9 % $ 3,653,344 95.2 % Special mention 19,938 0.9 % 43,896 3.5 % 19,846 4.8 % 83,680 2.2 % Substandard 51,814 2.4 % 30,249 2.4 % 17,790 4.3 % 99,853 2.6 % Total $ 2,166,603 100.0 % $ 1,256,830 100.0 % $ 413,444 100.0 % $ 3,836,877 100.0 % We monitor the delinquent status of the consumer portfolio on a monthly basis. Loans are considered nonperforming when interest and principal are 90 days or more past due or management has determined that a material deterioration in the borrower’s financial condition exists. The risk of loss is generally highest for nonperforming loans. The following tables present the recorded investment in consumer loan classes by performing and nonperforming status as of the dates presented: December 31, 2016 (dollars in thousands) Residential Mortgage % of Total Home Equity % of Total Installment and other consumer % of Total Consumer Construction % of Total Total % of Total Performing $ 692,064 98.6 % $ 478,845 99.3 % $ 65,744 99.8 % $ 5,906 100.0 % $ 1,242,559 98.9 % Nonperforming 9,918 1.4 % 3,439 0.7 % 108 0.2 % — — % 13,465 1.1 % Total $ 701,982 100.0 % $ 482,284 100.0 % $ 65,852 100.0 % $ 5,906 100.0 % $ 1,256,024 100.0 % December 31, 2015 (dollars in thousands) Residential Mortgage % of Total Home Equity % of Total Installment and other consumer % of Total Consumer Construction % of Total Total % of Total Performing $ 633,743 99.1 % $ 467,943 99.4 % $ 73,839 99.8 % $ 6,579 100.0 % $ 1,182,104 99.3 % Nonperforming 5,629 0.9 % 2,902 0.6 % 100 0.2 % — — % 8,631 0.7 % Total $ 639,372 100.0 % $ 470,845 100.0 % $ 73,939 100.0 % $ 6,579 100.0 % $ 1,190,735 100.0 % We individually evaluate all substandard and nonaccrual commercial loans greater than $0.5 million for impairment. Loans are considered to be impaired when based upon current information and events it is probable that we will be unable to collect all principal and interest payments due according to the original contractual terms of the loan agreement. All TDRs will be reported as an impaired loan for the remaining life of the loan, unless the restructuring agreement specifies an interest rate equal to or greater than the rate that would be accepted at the time of the restructuring for a new loan with comparable risk and it is expected that the remaining principal and interest will be fully collected according to the restructured agreement. For all TDRs, regardless of size, and all other impaired loans, we conduct further analysis to determine the probable loss and assign a specific reserve to the loan if deemed appropriate. The following tables summarize investments in loans considered to be impaired and related information on those impaired loans as of the dates presented: December 31, 2016 December 31, 2015 (dollars in thousands) Recorded Investment Unpaid Principal Balance Related Allowance Recorded Investment Unpaid Principal Balance Related Allowance With a related allowance recorded: Commercial real estate $ — $ — $ — $ — $ — $ — Commercial and industrial 964 2,433 771 — — — Commercial construction — — — 500 1,350 3 Consumer real estate 26 26 26 116 116 32 Other consumer 1 1 1 2 2 2 Total with a Related Allowance Recorded 991 2,460 798 618 1,468 37 Without a related allowance recorded: Commercial real estate 16,352 17,654 — 12,661 13,157 — Commercial and industrial 5,902 7,699 — 14,417 15,220 — Commercial construction 6,613 10,306 — 10,998 14,200 — Consumer real estate 12,053 12,849 — 6,845 7,521 — Other consumer 24 31 — 111 188 — Total without a Related Allowance Recorded 40,944 48,539 — 45,032 50,286 — Total: Commercial real estate 16,352 17,654 — 12,661 13,157 — Commercial and industrial 6,866 10,132 771 14,417 15,220 — Commercial construction 6,613 10,306 — 11,498 15,550 3 Consumer real estate 12,079 12,875 26 6,961 7,637 32 Other consumer 25 32 1 113 190 2 Total $ 41,935 $ 50,999 $ 798 $ 45,650 $ 51,754 $ 37 As of December 31, 2016, we had $41.9 million of impaired loans which included $18.4 million of acquired loans that experienced credit deterioration since the acquisition date. The following table summarizes investments in loans considered to be impaired and related information on those impaired loans for the years presented: For the Year Ended December 31, 2016 December 31, 2015 (dollars in thousands) Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized Without a related allowance recorded: Commercial real estate 17,496 144 14,622 597 Commercial and industrial 6,141 160 14,416 450 Commercial construction 7,723 162 10,581 329 Consumer real estate 11,939 523 6,902 364 Other consumer 35 1 117 1 Total without a Related Allowance Recorded 43,334 990 46,638 1,741 With a related allowance recorded: Commercial real estate — — — — Commercial and industrial 2,438 — — — Commercial construction — — 834 — Consumer real estate 28 2 120 7 Other consumer 2 — 2 — Total with a Related Allowance Recorded 2,468 2 956 7 Total: Commercial real estate 17,496 144 14,622 597 Commercial and industrial 8,579 160 14,416 450 Commercial construction 7,723 162 11,415 329 Consumer real estate 11,967 525 7,022 371 Other consumer 37 1 119 1 Total $ 45,802 $ 992 $ 47,594 $ 1,748 The following tables detail activity in the ALL for the periods presented: 2016 (dollars in thousands) Commercial Real Estate Commercial and Industrial Commercial Construction Consumer Real Estate Other Consumer Total Loans Balance at beginning of year $ 15,043 $ 10,853 $ 12,625 $ 8,400 $ 1,226 $ 48,147 Charge-offs (3,114 ) (6,810 ) (1,877 ) (1,657 ) (2,103 ) (15,561 ) Recoveries 692 722 21 433 356 2,224 Net (Charge-offs) Recoveries (2,422 ) (6,088 ) (1,856 ) (1,224 ) (1,747 ) (13,337 ) Provision for loan losses 7,355 6,045 3,230 (1,081 ) 2,416 17,965 Balance at End of Year $ 19,976 $ 10,810 $ 13,999 $ 6,095 $ 1,895 $ 52,775 2015 (dollars in thousands) Commercial Real Estate Commercial and Industrial Commercial Construction Consumer Real Estate Other Consumer Total Loans Balance at beginning of year $ 20,164 $ 13,668 $ 6,093 $ 6,333 $ 1,653 $ 47,911 Charge-offs (2,787 ) (5,463 ) (3,321 ) (2,167 ) (1,528 ) (15,266 ) Recoveries 3,545 605 143 495 326 5,114 Net Recoveries (Charge-offs) 758 (4,858 ) (3,178 ) (1,672 ) (1,202 ) (10,152 ) Provision for loan losses (5,879 ) 2,043 9,710 3,739 775 10,388 Balance at End of Year $ 15,043 $ 10,853 $ 12,625 $ 8,400 $ 1,226 $ 48,147 Loans acquired in the Merger were recorded at fair value with no carryover of the ALL. As of December 31, 2016, acquired loans from the Merger of $543.3 million were outstanding, which decreased from $673.3 million at December 31, 2015. Additional credit deterioration on acquired loans during 2016 in excess of the original credit discount embedded in the fair value determination on the date of acquisition, was recognized in the ALL through the provision for loan losses. The following tables present the ALL and recorded investments in loans by category as of December 31: 2016 Allowance for Loan Losses Portfolio Loans (dollars in thousands) Individually Evaluated for Impairment Collectively Evaluated for Impairment Total Individually Evaluated for Impairment Collectively Evaluated for Impairment Total Commercial real estate $ — $ 19,976 $ 19,976 $ 16,352 $ 2,482,124 $ 2,498,476 Commercial and industrial 771 10,039 10,810 6,866 1,394,169 1,401,035 Commercial construction — 13,999 13,999 6,613 449,271 455,884 Consumer real estate 26 6,069 6,095 12,079 1,178,093 1,190,172 Other consumer 1 1,894 1,895 25 65,827 65,852 Total $ 798 $ 51,977 $ 52,775 $ 41,935 $ 5,569,484 $ 5,611,419 2015 Allowance for Loan Losses Portfolio Loans (dollars in thousands) Individually Evaluated for Impairment Collectively Evaluated for Impairment Total Individually Evaluated for Impairment Collectively Evaluated for Impairment Total Commercial real estate $ — $ 15,043 $ 15,043 $ 12,661 $ 2,153,942 $ 2,166,603 Commercial and industrial — 10,853 10,853 14,417 1,242,413 1,256,830 Commercial construction 3 12,622 12,625 11,498 401,946 413,444 Consumer real estate 32 8,368 8,400 6,961 1,109,835 1,116,796 Other consumer 2 1,224 1,226 113 73,826 73,939 Total $ 37 $ 48,110 $ 48,147 $ 45,650 $ 4,981,962 $ 5,027,612

Premises and Equipment

Premises and Equipment	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Premises and Equipment	PREMISES AND EQUIPMENT The following table is a summary of premises and equipment as of the dates presented: December 31, (dollars in thousands) 2016 2015 Land $ 6,397 $ 8,699 Premises 52,696 52,968 Furniture and equipment 32,328 29,543 Leasehold improvements 7,293 7,186 98,714 98,396 Accumulated depreciation (53,715 ) (49,269 ) Total $ 44,999 $ 49,127 Depreciation expense related to premises and equipment was $5.0 million in 2016, $4.7 million in 2015 and $3.5 million in 2014. Certain banking facilities are leased under arrangements expiring at various dates until the year 2054 . We account for these leases on a straight-line basis due to escalation clauses. All leases are accounted for as operating leases, except for one capital lease. Rental expense for premises amounted to $4.1 million , $3.9 million and $2.7 million in 2016, 2015 and 2014. Included in the rental expense for premises are leases entered into with two S&T directors, which totaled $0.3 million each year in 2016, 2015 and 2014. Minimum annual rental and renewal option payments for each of the following five years and thereafter are approximately: (dollars in thousands) Operating Capital Total 2017 $ 3,388 $ 76 $ 3,464 2018 3,394 76 3,470 2019 3,430 76 3,506 2020 3,380 77 3,457 2021 3,401 77 3,478 Thereafter 57,864 534 58,398 Total $ 74,857 $ 916 $ 75,773

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	GOODWILL AND OTHER INTANGIBLE ASSETS The following table presents goodwill as of the dates presented: December 31, (dollars in thousands) 2016 2015 Balance at beginning of year $ 291,764 $ 175,820 Additions — 115,944 Other adjustments (94 ) — Balance at End of Year $ 291,670 $ 291,764 Goodwill represents the excess of the purchase price over the fair value of net assets acquired. Purchase accounting guidance allows for a reasonable period of time following an acquisition for the acquirer to obtain the information necessary to complete the accounting for a business combination. This period is known as the measurement period. Additional measurement period purchase accounting adjustments, primarily related to taxes from the Integrity merger, decreased goodwill by less than $0.1 million in 2016. Additional goodwill of $115.9 million was recorded during 2015, for our acquisition of Integrity. Refer to Note 2 Business Combinations for further details on the Integrity acquisition. Goodwill is reviewed for impairment annually or more frequently if it is determined that a triggering event has occurred. Based upon our qualitative assessment performed for our annual impairment analysis, we concluded that it is more likely than not that the fair value of the reporting units exceeds the carrying value. In general, the overall macroeconomic conditions and more specifically the economic conditions of the banking industry have been very good. Additionally, our overall performance has been good and we did not identify any other facts and circumstances causing us to conclude that it is more likely than not that the fair value of the reporting units would be less than the carrying value. The following table shows a summary of intangible assets as of the dates presented: December 31, (dollars in thousands) 2016 2015 Gross carrying amount at beginning of year $ 22,114 $ 16,401 Additions — 5,713 Accumulated amortization (17,204 ) (15,589 ) Balance at End of Year $ 4,910 $ 6,525 Intangible assets as of December 31, 2016 consisted of $4.5 million for core deposits, $0.1 million for wealth management relationships and $0.3 million for insurance contract relationships resulting from acquisitions. The addition of $5.7 million during 2015 was due to the core deposit intangible asset related to the acquisition of Integrity. We determined the amount of identifiable intangible assets based upon independent core deposit, wealth management and insurance contract valuations. Other intangible assets are evaluated for impairment whenever events or changes in circumstances indicate that their carrying amounts may not be recoverable. There were no triggering events in 2016 requiring an impairment analysis to be completed. Amortization expense on finite-lived intangible assets totaled $1.6 million , $1.8 million and $1.1 million for 2016, 2015 and 2014. The following is a summary of the expected amortization expense for finite-lived intangible assets, assuming no new additions, for each of the five years following December 31, 2016: (dollars in thousands) Amount 2017 $ 1,311 2018 812 2019 689 2020 588 2021 512 Total $ 3,912

Derivative Instruments and Hedg

Derivative Instruments and Hedging Activities	12 Months Ended
	Dec. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments and Hedging Activities	DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES The following table indicates the amounts representing the value of derivative assets and derivative liabilities at December 31: Derivatives (included in Other Assets) Derivatives (included in Other Liabilities) (dollars in thousands) 2016 2015 2016 2015 Derivatives not Designated as Hedging Instruments Interest Rate Swap Contracts—Commercial Loans Fair value $ 6,960 $ 11,295 $ 6,958 $ 11,276 Notional amount 232,396 245,595 232,396 245,595 Collateral posted — — 14,340 12,753 Interest Rate Lock Commitments—Mortgage Loans Fair value 236 261 — — Notional amount 8,490 9,894 — — Forward Sale Contracts—Mortgage Loans Fair value — — 27 5 Notional amount — — 8,216 9,800 Presenting offsetting derivatives that are subject to legally enforceable netting arrangements with the same party is permitted. For example, we may have a derivative asset and a derivative liability with the same counterparty to a swap transaction and are permitted to offset the asset position and the liability position resulting in a net presentation. The following table indicates the gross amounts of commercial loan swap derivative assets and derivative liabilities, the amounts offset and the carrying values in the Consolidated Balance Sheets at December 31: Derivatives (included in Other Assets) Derivatives (included in Other Liabilities) (dollars in thousands) 2016 2015 2016 2015 Derivatives not Designated as Hedging Instruments Gross amounts recognized $ 8,590 $ 11,295 $ 8,588 $ 11,276 Gross amounts offset (1,630 ) — (1,630 ) — Net amounts presented in the Consolidated Balance Sheets 6,960 11,295 6,958 11,276 Gross amounts not offset (1) — — (14,340 ) (12,573 ) Net Amount $ 6,960 $ 11,295 $ (7,382 ) $ (1,297 ) (1) Amounts represent posted collateral. The following table indicates the gain or loss recognized in income on derivatives for the years ended December 31: (dollars in thousands) 2016 2015 2014 Derivatives not Designated as Hedging Instruments Interest rate swap contracts—commercial loans $ (16 ) $ (8 ) $ (24 ) Interest rate lock commitments—mortgage loans (25 ) 26 150 Forward sale contracts—mortgage loans (22 ) 52 (90 ) Total Derivative(Loss) Gain $ (63 ) $ 70 $ 36

Mortgage Servicing Rights

Mortgage Servicing Rights	12 Months Ended
	Dec. 31, 2016
Transfers and Servicing of Financial Assets [Abstract]
Mortgage Servicing Rights	MORTGAGE SERVICING RIGHTS For the years ended December 31, 2016, 2015 and 2014, the 1-4 family mortgage loans that were sold to Fannie Mae amounted to $93.9 million , $76.8 million and $40.1 million . At December 31, 2016, 2015 and 2014 our servicing portfolio totaled $407.3 million , $361.2 million and $325.8 million . The following table indicates MSRs and the net carrying values: (dollars in thousands) Servicing Rights Valuation Allowance Net Carrying Value Balance at December 31, 2014 $ 3,108 $ (291 ) $ 2,817 Additions 856 — 856 Amortization (538 ) — (538 ) Temporary (impairment) recapture — 102 102 Balance at December 31, 2015 $ 3,426 $ (189 ) $ 3,237 Additions 1,047 — 1,047 Amortization (615 ) — (615 ) Temporary (impairment) recapture — 75 75 Balance at December 31, 2016 $ 3,858 $ (114 ) $ 3,744

Qualified Affordable Housing

Qualified Affordable Housing	12 Months Ended
	Dec. 31, 2016
Investments in Affordable Housing Projects [Abstract]
Qualified Affordable Housing Program	QUALIFIED AFFORDABLE HOUSING We invest in affordable housing projects primarily to satisfy our Community Reinvestment Act requirements. As a limited partner in these operating partnerships, we receive tax credits and tax deductions for losses incurred by the underlying properties. We use the cost method to account for these partnerships. Our total investment in qualified affordable housing projects was $11.7 million at December 31, 2016 and $15.0 million at December 31, 2015. We had no open commitments to fund current or future investments in qualified affordable housing projects at December 31, 2016 or December 31, 2015. Amortization expense, included in other noninterest expense in the Consolidated Statements of Net Income, was $3.3 million , $3.6 million and $4.1 million for December 31, 2016, 2015 and 2014. The amortization expense was offset by tax credits of $3.7 million , $4.0 million and $4.3 million for December 31, 2016, 2015 and 2014, as a reduction to our federal tax provision.

Deposits

Deposits	12 Months Ended
	Dec. 31, 2016
Banking and Thrift [Abstract]
Deposits	DEPOSITS The following table presents the composition of deposits at December 31 and interest expense for the years ended December 31: 2016 2015 2014 (dollars in thousands) Balance Interest Expense Balance Interest Expense Balance Interest Expense Noninterest-bearing demand $ 1,263,833 $ — $ 1,227,766 $ — $ 1,083,919 $ — Interest-bearing demand 638,300 111 616,188 818 335,099 19 Money market 936,461 4,199 605,184 1,299 376,612 572 Savings 1,050,131 2,002 1,061,265 1,712 1,027,095 1,607 Certificates of deposit 1,383,652 13,380 1,366,208 9,115 1,086,117 7,930 Total $ 5,272,377 $ 19,692 $ 4,876,611 $ 12,944 $ 3,908,842 $ 10,128 The aggregate of all certificates of deposit over $100,000, including Brokered CD's, was $671.5 million and $555.4 million at December 31, 2016 and 2015. The following table indicates the scheduled maturities of certificates of deposit at December 31, 2016: (dollars in thousands) Amount 2017 $ 1,017,744 2018 221,829 2019 48,890 2020 38,629 2021 48,438 Thereafter 8,122 Total $ 1,383,652

Short-Term Borrowings

Short-Term Borrowings	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Short-Term Borrowings	SHORT-TERM BORROWINGS Short-term borrowings are for terms under one year and were comprised of REPOs and FHLB advances. REPOs are overnight short-term investments and are not insured by the Federal Deposit Insurance Corporation, or FDIC. Securities pledged as collateral under these REPO financing arrangements cannot be sold or repledged by the secured party and are therefore accounted for as a secured borrowing. Securities with amortized cost of $53.1 million and carrying value of $52.9 million at December 31, 2016 and amortized cost of $67.0 million and carrying value of $ 66.9 million at December 31, 2015 were pledged as collateral for these secured transactions. The pledged securities are held in safekeeping at the Federal Reserve. Due to the overnight short-term nature of REPOs, potential risk due to a decline in the value of the pledged collateral is low. Collateral pledging requirements with REPOs are monitored daily. The following table represents the composition of short-term borrowings, the weighted average interest rate as of December 31 and interest expense for the years ended December 31: 2016 2015 2014 (dollars in thousands) Balance Weighted Average Interest Rate Interest Expense Balance Weighted Average Interest Rate Interest Expense Balance Weighted Average Interest Rate Interest Expense REPOs $ 50,832 0.01 % $ 5 $ 62,086 0.01 % $ 4 $ 30,605 0.01 % $ 3 FHLB advances 660,000 0.76 % 2,713 356,000 0.52 % 932 290,000 0.31 % 511 Total Short-term Borrowings $ 710,832 0.70 % $ 2,718 $ 418,086 0.44 % $ 936 $ 320,605 0.27 % $ 514

Long-Term Borrowings and Subord

Long-Term Borrowings and Subordinated Debt	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Long-Term Borrowings and Subordinated Debt	LONG-TERM BORROWINGS AND SUBORDINATED DEBT Long-term borrowings are for original terms greater than or equal to one year and are comprised of FHLB advances, a capital lease and junior subordinated debt securities. Our long-term borrowings at the Pittsburgh FHLB were $14.7 million as of December 31, 2016 and $117.0 million as of December 31, 2015. FHLB borrowings are secured by a blanket lien on residential mortgages and other real estate secured loans. Total loans pledged as collateral at the FHLB were $3.2 billion at December 31, 2016. We were eligible to borrow up to an additional $1.4 billion based on qualifying collateral, to a maximum borrowing capacity of $2.3 billion at December 31, 2016. The following table represents the balance of long-term borrowings, the weighted average interest rate as of December 31 and interest expense for the years ended December 31: (dollars in thousand) 2016 2015 2014 Long-term borrowings $ 14,713 $ 117,043 $ 19,442 Weighted average interest rate 2.91 % 0.81 % 3.00 % Interest expense $ 670 $ 790 $ 617 Scheduled annual maturities and average interest rates for all of our long-term debt, including a capital lease of $0.1 million , for each of the five years and thereafter subsequent to December 31, 2016 are as follows: (dollars in thousands) Balance Average Rate 2017 $ 2,412 3.52 % 2018 2,496 3.60 % 2019 2,514 3.13 % 2020 2,004 3.22 % 2021 1,057 3.44 % Thereafter 4,230 1.84 % Total $ 14,713 2.94 % Junior Subordinated Debt Securities The following table represents the composition of junior subordinated debt securities at December 31 and the interest expense for the years ended December 31: 2016 2015 2014 (dollars in thousands) Balance Interest Expense Balance Interest Expense Balance Interest Expense 2006 Junior subordinated debt $ 25,000 $ 580 $ 25,000 $ 554 $ 25,000 $ 463 2008 Junior subordinated debt—trust preferred securities 20,619 854 20,619 773 20,619 759 Total $ 45,619 $ 1,434 $ 45,619 $ 1,327 $ 45,619 $ 1,222 The following table summarizes the key terms of our junior subordinated debt securities: (dollars in thousands) 2006 Junior Subordinated Debt 2008 Trust Preferred Securities Junior Subordinated Debt $25,000 — Trust Preferred Securities — $20,619 Stated Maturity Date 12/15/2036 3/15/2038 Optional redemption date at par Any time after 9/15/2011 Any time after 3/15/2013 Regulatory Capital Tier 2 Tier 1 Interest Rate 3 month LIBOR plus 160 bps 3 month LIBOR plus 350 bps Interest Rate at December 31, 2016 2.56% 4.46% We completed a private placement of the trust preferred securities to a financial institution during the first quarter of 2008. As a result, we own 100 percent of the common equity of STBA Capital Trust I. The trust was formed to issue mandatorily redeemable capital securities to third-party investors. The proceeds from the sale of the securities and the issuance of the common equity by STBA Capital Trust I were invested in junior subordinated debt securities issued by us. The third party investors are considered the primary beneficiaries; therefore, the trust qualifies as a VIE, but is not consolidated into our financial statements. STBA Capital Trust I pays dividends on the securities at the same rate as the interest paid by us on the junior subordinated debt held by STBA Capital Trust I. On March 4, 2015 we assumed a $13.5 million junior subordinated debt from the acquisition of Integrity. On March 5, 2015, we paid off $8.5 million and on June 18, 2015, we paid off the remaining $5.0 million .

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES Commitments The following table sets forth our commitments and letters of credit as of the dates presented: December 31, (dollars in thousands) 2016 2015 Commitments to extend credit $ 1,509,696 $ 1,619,854 Standby letters of credit 84,534 97,676 Total $ 1,594,230 $ 1,717,530 Estimates of the fair value of these off-balance sheet items were not made because of the short-term nature of these arrangements and the credit standing of the counterparties. Our allowance for unfunded loan commitments totaled $2.6 million at December 31, 2016 and $2.5 million at December 31, 2015. We have future commitments with third party vendors for data processing and communication charges. Data processing and communication expense was $10.4 million , $11.7 million and $9.8 million for 2016, 2015 and 2014. Included in this expense was $1.3 million of one-time merger related expenses in 2015. There were no data processing and communication merger related expenses in 2016 or 2014. The following table sets forth the future estimated payments related to data processing and communication charges for each of the five years following December 31, 2016: (dollars in thousands) Total 2017 $ 11,671 2018 12,046 2019 12,451 2020 12,875 2021 13,315 Total $ 62,358 Litigation In the normal course of business, we are subject to various legal and administrative proceedings and claims. While any type of litigation contains a level of uncertainty, we believe that the outcome of such proceedings or claims pending will not have a material adverse effect on our consolidated financial position or results of operations.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income Taxes	INCOME TAXES Income tax expense (benefit) for the years ended December 31 is comprised of: (dollars in thousands) 2016 2015 2014 Federal Current $ 24,521 $ 24,825 $ 15,979 Deferred 665 (427 ) 1,536 Total Federal 25,186 24,398 17,515 State Current 248 — — Deferred (129 ) — — Total State 119 — — Total Federal and State $ 25,305 $ 24,398 $ 17,515 The provision for income taxes differs from the amount computed by applying the statutory federal income tax rate to income before income taxes. We ordinarily generate an annual effective tax rate that is less than the federal statutory rate of 35 percent primarily due to benefits resulting from tax-exempt interest, excludable dividend income, tax-exempt income on BOLI and tax benefits associated with LIHTC from certain partnership investments. The statutory to effective tax rate reconciliation for the years ended December 31 is as follows: 2016 2015 2014 Statutory tax rate 35.0 % 35.0 % 35.0 % Low income housing tax credits (3.8 )% (4.4 )% (5.8 )% Tax-exempt interest (4.4 )% (4.1 )% (4.6 )% Bank owned life insurance (0.8 )% (0.8 )% (0.8 )% Other 0.2 % 1.0 % (0.6 )% Effective Tax Rate 26.2 % 26.7 % 23.2 % Significant components of our temporary differences were as follows at December 31: (dollars in thousands) 2016 2015 Deferred Tax Liabilities: Net unrealized holding gains on securities available-for-sale $ (2,557 ) $ (3,563 ) Prepaid pension (2,770 ) (2,865 ) Deferred loan income (3,815 ) (2,847 ) Depreciation on premises and equipment (1,239 ) (1,226 ) Other (1,766 ) (809 ) Total Deferred Tax liabilities (12,147 ) (11,310 ) Deferred Tax Assets: Allowance for loan losses 19,446 17,740 Purchase accounting adjustments 365 1,298 Other employee benefits 3,983 2,556 Low income housing partnerships 4,845 4,531 Net adjustment to funded status of pension 10,018 12,425 Impairment of securities 1,318 1,354 State net operating loss carryforwards 3,114 2,670 Other 4,984 6,155 Gross Deferred Tax Assets 48,073 48,729 Less: Valuation allowance (3,114 ) (2,670 ) Total Deferred Tax Assets 44,959 46,059 Net Deferred Tax Asset $ 32,812 $ 34,749 We establish a valuation allowance when it is more likely than not that we will not be able to realize the benefit of the deferred tax assets. Except for Pennsylvania net operating losses, or NOLs, we have determined that a valuation allowance is unnecessary for the deferred tax assets because it is more likely than not that these assets will be realized through future reversals of existing temporary differences and through future taxable income. The valuation allowance is reviewed quarterly and adjusted based on management’s assessments of realizable deferred tax assets. Gross deferred tax assets were reduced by a valuation allowance of $3.1 million in 2016 related to Pennsylvania income tax NOLs. The Pennsylvania NOL carryforwards total $31.2 million and will expire in the years 2020 - 2036 . Unrecognized Tax Benefits The following table reconciles the change in Federal and State gross unrecognized tax benefits, or UTB, for the years ended December 31: (dollars in thousands) 2016 2015 2014 Balance at beginning of year $ 1,102 $ 284 $ 1,902 Prior period tax positions Increase — 818 55 Decrease (449 ) — (1,673 ) Current period tax positions 151 — — Reductions for statute of limitations expirations — — — Balance at End of Year $ 804 $ 1,102 $ 284 Amount That Would Impact the Effective Tax Rate if Recognized $ 610 $ 542 $ 184 We classify interest and penalties as an element of tax expense. We monitor changes in tax statutes and regulations to determine if significant changes will occur over the next 12 months. As of December 31, 2016, no significant changes to UTB are projected, however, tax audit examinations are possible. The UTB balance for the years ended December 31, 2016, 2015 and 2014 include a cumulative amount of $0.1 million related to interest in the Consolidated Balance Sheets. We recognized insignificant amounts of interest in 2016, 2015 and 2014 in the Consolidated Statements of Net Income. During 2016, the IRS completed its examination of our 2013 tax year. The examination was closed with no material adjustments impacting tax expense. As of December 31, 2016, all income tax returns filed for the tax years 2014 and 2015 remain subject to examination by the IRS.

Tax Effects on Other Comprehens

Tax Effects on Other Comprehensive Income (Loss)	12 Months Ended
	Dec. 31, 2016
Equity [Abstract]
Tax Effects on Other Comprehensive Income (Loss)	TAX EFFECTS ON OTHER COMPREHENSIVE INCOME (LOSS) The following tables present the tax effects of the components of other comprehensive income (loss) for the years ended December 31: (dollars in thousands) Pre-Tax Amount Tax (Expense) Benefit Net of Tax Amount 2016 Net change in unrealized gains on securities available-for-sale $ (2,899 ) $ 1,006 $ (1,893 ) Net available-for-sale securities losses (gains) reclassified into earnings — — — Adjustment to funded status of employee benefit plans 6,974 (2,408 ) 4,566 Other Comprehensive Income (Loss) $ 4,075 $ (1,402 ) $ 2,673 2015 Net change in unrealized gains on securities available-for-sale $ (663 ) $ 232 $ (431 ) Net available-for-sale securities losses reclassified into earnings 34 (12 ) 22 Adjustment to funded status of employee benefit plans (3,551 ) 1,336 (2,215 ) Other Comprehensive Income (Loss) $ (4,180 ) $ 1,556 $ (2,624 ) 2014 Net change in unrealized gains on securities available-for-sale $ 11,825 $ (4,139 ) $ 7,686 Net available-for-sale securities gains reclassified into earnings (41 ) 15 (26 ) Adjustment to funded status of employee benefit plans (13,394 ) 4,595 (8,799 ) Other Comprehensive Income (Loss) $ (1,610 ) $ 471 $ (1,139 )

Employee Benefits

Employee Benefits	12 Months Ended
	Dec. 31, 2016
Compensation and Retirement Disclosure [Abstract]
Employee Benefits	EMPLOYEE BENEFITS We maintain a qualified defined benefit pension plan, or Plan, covering substantially all employees hired prior to January 1, 2008. The benefits are based on years of service and the employee’s compensation for the highest five consecutive years in the last ten years . Contributions are intended to provide for benefits attributed to employee service to date and for those benefits expected to be earned in the future. On January 25, 2016, the Board of Directors approved an amendment to freeze benefit accruals under the qualified and nonqualified defined benefit pension plans effective March 31, 2016. This change will result in no additional benefits being earned by participants in those plans based on service or pay after March 31, 2016. The Plan was previously closed to new participants effective December 31, 2007. The following table summarizes the activity in the benefit obligation and Plan assets deriving the funded status, which is recorded in other liabilities in the Consolidated Balance Sheets: (dollars in thousands) 2016 2015 Change in Projected Benefit Obligation Projected benefit obligation at beginning of year $ 109,747 $ 113,124 Service cost 463 2,601 Interest cost 4,296 4,425 Actuarial loss (gain) 3,575 (4,257 ) Curtailments (6,997 ) — Benefits paid (5,250 ) (6,146 ) Projected Benefit Obligation at End of Year $ 105,834 $ 109,747 Change in Plan Assets Fair value of plan assets at beginning of year $ 84,585 $ 93,486 Actual return on plan assets 8,376 (2,755 ) Benefits paid (5,250 ) (6,146 ) Fair Value of Plan Assets at End of Year $ 87,711 $ 84,585 Funded Status $ (18,123 ) $ (25,162 ) The following table sets forth the amounts recognized in accumulated other comprehensive income (loss) at December 31: (dollars in thousands) 2016 2015 Prior service credit $ — $ (1,029 ) Net actuarial loss 26,013 34,376 Total (Before Tax Effects) $ 26,013 $ 33,347 Below are the actuarial weighted average assumptions used in determining the benefit obligation: 2016 2015 Discount rate 4.00 % 4.25 % Rate of compensation increase (1) — % 3.00 % (1) Rate of compensation increase is not applicable for 2016 due to the amendment to freeze benefit accruals under the qualified and nonqualified defined benefit pension plans effective March 31, 2016 The following table summarizes the components of net periodic pension cost and other changes in Plan assets and benefit obligations recognized in other comprehensive income (loss) for the years ended December 31: (dollars in thousands) 2016 2015 2014 Components of Net Periodic Pension Cost Service cost—benefits earned during the period $ 463 $ 2,601 $ 2,369 Interest cost on projected benefit obligation 4,296 4,425 4,470 Expected return on plan assets (5,780 ) (7,180 ) (6,907 ) Amortization of prior service credit (11 ) (138 ) (137 ) Recognized net actuarial loss 2,345 2,028 941 Curtailment (gain) (1,017 ) — — Net Periodic Pension Expense $ 296 $ 1,736 $ 736 Other Changes in Plan Assets and Benefit Obligation Recognized in Other Comprehensive Income (Loss) Net actuarial (gain) loss $ (6,018 ) $ 5,678 $ 13,294 Recognized net actuarial loss (2,345 ) (2,028 ) (941 ) Recognized prior service credit 1,029 138 137 Total (Before Tax Effects) $ (7,334 ) $ 3,788 $ 12,490 Total Recognized in Net Benefit Cost and Other Comprehensive (Loss)/Income (Before Tax Effects) $ (7,038 ) $ 5,524 $ 13,226 The following table summarizes the actuarial weighted average assumptions used in determining net periodic pension cost: 2016 2015 2014 Discount rate 4.25 % 4.00 % 4.75 % Rate of compensation increase 3.00 % 3.00 % 3.00 % Expected return on assets 7.50 % 8.00 % 8.00 % The net actuarial loss included in accumulated other comprehensive income (loss) expected to be recognized in net periodic pension cost during the year ended December 31, 2017 is $1.9 million . There will be no prior service credit recognized due to the amendment to freeze benefit accruals under the qualified and nonqualified defined benefit pension plans. The accumulated benefit obligation for the Plan was $105.8 million at December 31, 2016 and $101.6 million at December 31, 2015. We consider many factors when setting the assumed rate of return on Plan assets. As a general guideline the assumed rate of return is equal to the weighted average of the expected returns for each asset category and is estimated based on historical returns as well as expected future returns. The weighted average discount rate is derived from corporate yield curves. S&T Bank’s Retirement Plan Committee determines the investment policy for the Plan. In general, the targeted asset allocation is 50 percent to 70 percent equities and 30 percent to 50 percent fixed income. A strategic allocation within each asset class is employed based on the Plan’s time horizon, risk tolerances, performance expectations and asset class preferences. Investment managers have discretion to invest in any equity or fixed-income asset class, subject to the securities guidelines of the Plan’s Investment Policy Statement. At this time, S&T Bank is not required to make a cash contribution to the Plan in 2017. No contributions were made during 2016. The following table provides information regarding estimated future benefit payments to be paid in each of the next five years and in the aggregate for the five years thereafter: (dollars in thousands) Amount 2017 $ 6,788 2018 6,855 2019 6,833 2020 6,748 2021 6,847 2022 - 2026 32,361 We also have nonqualified supplemental executive pension plans, or SERPs, for certain key employees. The SERPs are unfunded. The projected benefit obligations related to the SERPs were $4.7 million and $4.0 million at December 31, 2016 and 2015. These amounts also represent the net amount recognized in the statement of financial position for the SERPs. Net periodic benefit costs for the SERPs were $0.5 million , $0.6 million and $0.4 million for each of the years ended December 31, 2016, 2015 and 2014. Additionally, $2.5 million and $2.1 million before tax was reflected in accumulated other comprehensive income (loss) at both December 31, 2016 and 2015, in relation to the SERPs. The actuarial assumptions used for the SERPs are the same as those used for the Plan. We maintain a Thrift Plan, a qualified defined contribution plan, in which substantially all employees are eligible to participate. We make matching contributions to the Thrift Plan up to 3.5 percent of participants’ eligible compensation and may make additional profit-sharing contributions as provided by the Thrift Plan. Expense related to these contributions amounted to $1.7 million in 2016, $1.5 million in 2015 and $1.3 million in 2014. Fair Value Measurements The following tables present our Plan assets measured at fair value on a recurring basis by fair value hierarchy level at December 31, 2016 and 2015. There were no transfers between Level 1 and Level 2 for items of a recurring basis during the periods presented. There were no purchases or transfers of Level 3 plan assets in 2016. December 31, 2016 Fair Value Asset Classes (1) (dollars in thousands) Level 1 Level 2 Level 3 Total Cash and cash equivalents (2) $ — $ 3,336 $ — $ 3,336 Fixed income (3) 27,279 — — 27,279 Equities: Equity index mutual funds—international (4) 3,362 — — 3,362 Domestic individual equities (5) 53,636 — — 53,636 Total Assets at Fair Value $ 84,277 $ 3,336 $ — $ 87,613 (1) Refer to Note 1 Summary of Significant Accounting Policies, Fair Value Measurements for a description of levels within the fair value hierarchy. (2) This asset class includes FDIC insured money market instruments. (3) This asset class includes a variety of fixed income mutual funds which primarily invest in investment grade rated securities. Investment managers have discretion to invest in fixed income related securities including futures, options and other derivatives. Investments may be made in currencies other than the U.S. dollar. (4) The sole investment within this asset class is the Harbor International Institutional Fund. (5) This asset class includes individual domestic equities invested in an active all-cap strategy. It may also include convertible bonds. December 31, 2015 Fair Value Asset Classes (1) (dollars in thousands) Level 1 Level 2 Level 3 Total Cash and cash equivalents (2) $ — $ 3,371 $ — $ 3,371 Fixed income (3) 27,054 — — 27,054 Equities: Equity index mutual funds—international (4) 3,421 — — 3,421 Domestic individual equities (5) 50,739 — — 50,739 Total Assets at Fair Value $ 81,214 $ 3,371 $ — $ 84,585 (1) Refer to Note 1 Summary of Significant Accounting Policies, Fair Value Measurements for a description of levels within the fair value hierarchy. (2) This asset class includes FDIC insured money market instruments. (3) This asset class includes a variety of fixed income mutual funds which primarily invest in investment grade rated securities. Investment managers have discretion to invest in fixed income related securities including futures, options and other derivatives. Investments may be made in currencies other than the U.S. dollar. (4) The sole investment within this asset class is MSCI EAFE Index iShares. (5) This asset class includes individual domestic equities invested in an active all-cap strategy. It may also include convertible bonds.

Incentive and Restricted Stock

Incentive and Restricted Stock Plan and Dividend Reinvestment Plan	12 Months Ended
	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Incentive and Restricted Stock Plan and Dividend Reinvestment Plan	INCENTIVE AND RESTRICTED STOCK PLAN AND DIVIDEND REINVESTMENT PLAN We adopted an Incentive Stock Plan in 2014 that provides for cash performance awards and for granting incentive stock options, nonstatutory stock options, restricted stock, restricted stock units and appreciation rights. A maximum of 750,000 shares of our common stock are available for awards granted under the 2014 Incentive Plan and the plan expires ten years from the date of board approval. Stock Options As of December 31, 2016, no nonstatutory stock options were outstanding under the 2014 Stock Plan. The fair value of nonstatutory stock option awards under the 2003 Stock Plan were estimated on the date of grant using the Black-Scholes valuation model, which is dependent upon certain assumptions. We used the simplified method in developing the estimated life of the option, whereby the expected life is presumed to be the midpoint between the vesting date and the end of the contractual term. There have been no nonstatutory stock options granted since 2006. The following table summarizes activity for nonstatutory stock options for the years ended December 31: 2016 2015 2014 Number of Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Term Number of Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Term Number of Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Term Outstanding at beginning of year — $ — 155,500 $ 37.86 428,900 $ 37.36 Granted — — — — — — Exercised — — — — — — Forfeited — — — — (273,400 ) 37.08 Expired — — (155,500 ) 37.86 — — Outstanding at End of Year — $ — 0.0 years — $ — 0.0 years 155,500 $ 37.86 1.0 year Exercisable at End of Year — $ — 0.0 years — $ — 0.0 years 155,500 $ 37.86 1.0 year The aggregate intrinsic value of options outstanding and exercisable was zero as of December 31, 2014. The aggregate intrinsic value represents the total pretax intrinsic value (the difference between our closing stock price on the last trading day of the fourth quarter and the exercise price, multiplied by the number of in-the-money options) that would have been received by the option holders had all option holders exercised the options on December 31, 2014. Restricted Stock We periodically issue restricted stock to employees and directors, pursuant to our 2014 Stock Plan. As of December 31, 2016, 278,939 restricted shares have been granted under the 2014 Stock Plan. During 2016, 2015, and 2014, we granted 15,613 , 16,142 and 13,824 restricted shares of common stock to outside directors under the 2014 Stock Plan. The grants are part of the compensation arrangement approved by the Compensation and Benefits Committee whereby the directors receive compensation in both the form of cash and restricted shares of common stock. These shares fully vest one year after the date of grant. The closing price of our stock is used to determine the fair value on the date of grant. During 2016, 2015, and 2014, we granted 95,030 , 71,699 and 66,631 restricted shares of common stock to senior management under our Long Term Incentive Plan, or LTIP. The restricted shares granted under the LTIP consist of both time and performance-based awards. The awards were granted in accordance with performance levels set by the Compensation and Benefits Committee. Vesting for the time-based awards is 50 percent after two years and the remaining 50 percent at the end of the third year. The performance-based awards vest at the end of the three -year period. During the vesting period, if the recipient leaves S&T before the end of the vesting period, shares will be forfeited except in the case of retirement, disability or death where accelerated vesting provisions are defined within the awards agreement. The average of the high and low prices of the stock is used to determine the fair value on the date of grant. Compensation expense for time-based restricted stock is recognized ratably over the period of service, generally the entire vesting period, based on fair value on the grant date. Compensation expense for performance-based restricted stock is recognized ratably over the remaining vesting period once the likelihood of meeting the performance measure is probable.During 2016, 2015 and 2014, we recognized compensation expense of $2.5 million , $1.7 million and $0.9 million and realized a tax benefit of $0.9 million , $0.6 million and $0.3 million related to restricted stock grants. The following table provides information about restricted stock granted under the 2014 Stock Plan for the years ended December 31: Restricted Stock Weighted Average Grant Date Fair Value Non-vested at December 31, 2014 79,824 $ 23.24 Granted 87,841 28.71 Vested 14,126 23.57 Forfeited 3,183 26.15 Non-vested at December 31, 2015 150,356 $ 26.34 Granted 110,643 25.58 Vested 32,164 25.03 Forfeited 3,335 26.04 Non-vested at December 31, 2016 225,500 $ 26.16 As of December 31, 2016, there was $2.5 million of total unrecognized compensation cost related to restricted stock that will be recognized as compensation expense over a weighted average period of 1.58 years. Dividend Reinvestment Plan We also sponsor a Dividend Reinvestment and Stock Purchase Plan, or Dividend Plan, where shareholders may purchase shares of S&T common stock at the average fair value with reinvested dividends and voluntary cash contributions. The plan administrator and transfer agent may purchase shares directly from us from shares held in treasury or purchase shares in the open market to fulfill the Dividend Plan’s needs.

Parent Company Condensed Financ

Parent Company Condensed Financial Information	12 Months Ended
	Dec. 31, 2016
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Parent Company Condensed Financial Information	PARENT COMPANY CONDENSED FINANCIAL INFORMATION The following condensed financial statements summarize the financial position of S&T Bancorp, Inc. as of December 31, 2016 and 2015 and the results of its operations and cash flows for each of the three years ended December 31, 2016, 2015 and 2014. BALANCE SHEETS December 31, (dollars in thousands) 2016 2015 ASSETS Cash $ 17,057 $ 12,595 Investments in: Bank subsidiary 819,531 777,795 Nonbank subsidiaries 21,980 20,624 Other assets 4,694 2,530 Total Assets $ 863,262 $ 813,544 LIABILITIES Long-term debt $ 20,619 $ 20,619 Other liabilities 687 688 Total Liabilities 21,306 21,307 Total Shareholders’ Equity 841,956 792,237 Total Liabilities and Shareholders’ Equity $ 863,262 $ 813,544 STATEMENTS OF NET INCOME Years ended December 31, (dollars in thousands) 2016 2015 2014 Dividends from subsidiaries $ 34,134 $ 75,413 $ 46,414 Investment income 17 19 19 Interest expense on long-term debt 854 773 759 Other expenses 2,315 2,138 2,014 Income before Equity in Undistributed Net Income of Subsidiaries 30,982 72,521 43,660 Equity in undistributed net income (distribution in excess of net income) of: Bank subsidiary 40,051 (5,064 ) 13,351 Nonbank subsidiaries 359 (376 ) 899 Net Income $ 71,392 $ 67,081 $ 57,910 STATEMENTS OF CASH FLOWS Years ended December 31, (dollars in thousands) 2016 2015 2014 OPERATING ACTIVITIES Net Income $ 71,392 $ 67,081 $ 57,910 Equity in undistributed (earnings) losses of subsidiaries (40,410 ) 5,440 (14,250 ) Tax benefit from stock-based compensation (9 ) (53 ) (16 ) Other 379 3,059 (106 ) Net Cash Provided by Operating Activities 31,352 75,527 43,538 INVESTING ACTIVITIES Net investments in subsidiaries — (38,404 ) — Acquisitions — (29,510 ) — Net Cash Used in Investing Activities — (67,914 ) — FINANCING ACTIVITIES Repayment of junior subordinated debt — (8,500 ) — (Purchase) Sale of treasury shares, net (115 ) (112 ) (163 ) Cash dividends paid to common shareholders (26,784 ) (24,487 ) (20,215 ) Tax benefit from stock-based compensation 9 53 16 Net Cash Used in Financing Activities (26,890 ) (33,046 ) (20,362 ) Net increase (decrease) in cash 4,462 (25,433 ) 23,176 Cash at beginning of year 12,595 38,028 14,852 Cash at End of Year $ 17,057 $ 12,595 $ 38,028

Regulatory Matters

Regulatory Matters	12 Months Ended
	Dec. 31, 2016
Banking and Thrift [Abstract]
Regulatory Matters	REGULATORY MATTERS We are subject to various regulatory capital requirements administered by the federal banking agencies. Failure to meet the minimum capital requirements can initiate certain mandatory and possibly additional discretionary actions by regulators that, if undertaken, could have a direct material effect on our consolidated financial statements. Under capital guidelines and the regulatory framework for prompt corrective action, we must meet specific capital guidelines that involve quantitative measures of our assets, liabilities and certain off-balance sheet items as calculated under regulatory accounting practices. Our capital amounts and classification are also subject to qualitative judgments by the regulators about risk weightings and other factors. The most recent notifications from the Federal Reserve and the FDIC categorized S&T and S&T Bank as well capitalized under the regulatory framework for corrective action. There have been no conditions or events that we believe have changed S&T or S&T Bank’s status during 2016 and 2015. Common equity tier 1 capital includes common stock and related surplus plus retained earnings, less goodwill and intangible assets subject to a limitation and certain deferred tax assets subject to a limitation. In addition, we made a one-time permanent election to exclude accumulated other comprehensive income from capital. For regulatory purposes, trust preferred securities totaling $20.0 million , issued by an unconsolidated trust subsidiary of S&T underlying junior subordinated debt, are included in Tier 1 capital for S&T. Total capital consists of Tier 1 capital plus junior subordinated debt and the ALL subject to limitation. We currently have $25.0 million in junior subordinated debt which is included in Tier 2 capital for S&T in accordance with current regulatory reporting requirements. Quantitative measures established by regulation to ensure capital adequacy require us to maintain minimum amounts and ratios of Total, Tier 1 and Common Equity Tier 1 capital to risk-weighted assets and Tier 1 capital to average assets. As of December 31, 2016 and 2015, we met all capital adequacy requirements to which we are subject. The following table summarizes risk-based capital amounts and ratios for S&T and S&T Bank: Actual Minimum Regulatory Capital Requirements To be Well Capitalized Under Prompt Corrective Action Provisions (dollars in thousands) Amount Ratio Amount Ratio Amount Ratio As of December 31, 2016 Leverage Ratio S&T $ 582,155 8.98 % $ 259,170 4.00 % $ 323,963 5.00 % S&T Bank 542,048 8.39 % 258,460 4.00 % 323,075 5.00 % Common Equity Tier 1 (to Risk-Weighted Assets) S&T 562,155 10.04 % 252,079 4.50 % 364,114 6.50 % S&T Bank 542,048 9.71 % 251,213 4.50 % 362,864 6.50 % Tier 1 Capital (to Risk-Weighted Assets) S&T 582,155 10.39 % 336,105 6.00 % 448,140 8.00 % S&T Bank 542,048 9.71 % 334,951 6.00 % 446,601 8.00 % Total Capital (to Risk-Weighted Assets) S&T 664,184 11.86 % 448,140 8.00 % 560,175 10.00 % S&T Bank 622,469 11.15 % 446,602 8.00 % 558,252 10.00 % As of December 31, 2015 Leverage Ratio S&T $ 535,234 8.96 % $ 238,841 4.00 % $ 298,551 5.00 % S&T Bank 502,114 8.43 % 238,121 4.00 % 297,651 5.00 % Common Equity Tier 1 (to Risk-Weighted Assets) S&T 515,234 9.77 % 237,315 4.50 % 342,788 6.50 % S&T Bank 502,114 9.55 % 236,482 4.50 % 341,584 6.50 % Tier 1 Capital (to Risk-Weighted Assets) S&T 535,234 10.15 % 316,419 6.00 % 421,892 8.00 % S&T Bank 502,114 9.55 % 315,309 6.00 % 420,412 8.00 % Total Capital (to Risk-Weighted Assets) S&T 611,859 11.60 % 421,892 8.00 % 527,366 10.00 % S&T Bank 577,824 11.00 % 420,412 8.00 % 525,515 10.00 %

Segments

Segments	12 Months Ended
	Dec. 31, 2016
Segment Reporting [Abstract]
Segments	SEGMENTS We operate three reportable operating segments: Community Banking, Insurance and Wealth Management. • Our Community Banking segment offers services which include accepting time and demand deposits and originating commercial and consumer loans. • Our Insurance segment includes a full-service insurance agency offering commercial property and casualty insurance, group life and health coverage, employee benefit solutions and personal insurance lines. • Our Wealth Management segment offers discount brokerage services, services as executor and trustee under wills and deeds, guardian and custodian of employee benefits and other trust and brokerage services, as well as a registered investment advisor that manages private investment accounts for individuals and institutions. The following represents total assets by reportable operating segment as of December 31: (dollars in thousands) 2016 2015 Community Banking $ 6,930,712 $ 6,305,046 Insurance 9,226 9,619 Wealth Management 3,115 3,689 Total Assets $ 6,943,053 $ 6,318,354 The following tables provide financial information for our three segments. The financial results of the business segments include allocations for shared services based on an internal analysis that supports line of business and branch performance measurement. Shared services include expenses such as employee benefits, occupancy expense, computer support and other corporate overhead. Even with these allocations, the financial results are not necessarily indicative of the business segments’ financial condition and results of operations as if they existed as independent entities. The information provided under the caption “Eliminations” represents operations not considered to be reportable segments and/or general operating expenses and eliminations and adjustments, which are necessary for purposes of reconciling to the Consolidated Financial Statements. For the Year Ended December 31, 2016 (dollars in thousands) Community Banking Insurance Wealth Management Eliminations Consolidated Interest income $ 227,756 $ 2 $ 459 $ (443 ) $ 227,774 Interest expense 24,851 — — (336 ) 24,515 Net interest income 202,905 2 459 (107 ) 203,259 Provision for loan losses 17,965 — — — 17,965 Noninterest income 37,717 4,794 10,443 1,681 54,635 Noninterest expense 120,744 4,582 9,751 1,574 136,651 Depreciation expense 4,905 45 16 — 4,966 Amortization of intangible assets 1,543 50 22 — 1,615 Provision for income taxes 24,872 42 391 — 25,305 Net Income $ 70,593 $ 77 $ 722 $ — $ 71,392 For the Year Ended December 31, 2015 (dollars in thousands) Community Banking Insurance Wealth Management Eliminations Consolidated Interest income $ 203,439 $ 2 $ 508 $ (401 ) $ 203,548 Interest expense 16,678 — — (681 ) 15,997 Net interest income 186,761 2 508 280 187,551 Provision for loan losses 10,388 — — — 10,388 Noninterest income 34,106 5,035 11,412 480 51,033 Noninterest expense 115,998 4,365 9,037 760 130,160 Depreciation expense 4,664 50 25 — 4,739 Amortization of intangible assets 1,738 50 30 — 1,818 Provision for income taxes 23,209 200 989 — 24,398 Net Income $ 64,870 $ 372 $ 1,839 $ — $ 67,081 For the Year Ended December 31, 2014 (dollars in thousands) Community Banking Insurance Wealth Management Eliminations Consolidated Interest income $ 160,403 $ 2 $ 518 $ (400 ) $ 160,523 Interest expense 13,989 — — (1,508 ) 12,481 Net interest income 146,414 2 518 1,108 148,042 Provision for loan losses 1,715 — — — 1,715 Noninterest income 29,443 5,279 11,297 319 46,338 Noninterest expense 97,733 4,313 9,173 1,427 112,646 Depreciation expense 3,387 51 27 — 3,465 Amortization of intangible assets 1,039 51 39 — 1,129 Provision (benefit) for income taxes 16,311 303 901 — 17,515 Net Income $ 55,672 $ 563 $ 1,675 $ — $ 57,910

Selected Financial Data

Selected Financial Data	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Selected Financial Data	SELECTED FINANCIAL DATA The following table presents selected financial data for the most recent eight quarters. 2016 2015 (dollars in thousands, except per share data) (unaudited) Fourth Quarter Third Quarter Second Quarter First Quarter Fourth Quarter Third Quarter Second Quarter First Quarter SUMMARY OF OPERATIONS Interest income $ 59,096 $ 57,808 $ 55,850 $ 55,019 $ 53,353 $ 53,669 $ 52,611 $ 43,916 Interest expense 6,638 6,353 6,142 5,382 4,468 4,073 3,800 3,657 Provision for loan losses 5,586 2,516 4,848 5,014 3,915 3,206 2,059 1,207 Net Interest Income After Provision For Loan Losses 46,872 48,939 44,860 44,623 44,970 46,390 46,752 39,052 Security (losses) gains, net — — — — — — (34 ) — Noninterest income 12,922 13,448 12,448 15,817 13,084 12,481 13,417 12,084 Noninterest expense 35,625 34,439 34,753 38,416 33,817 33,829 35,449 33,621 Income Before Taxes 24,169 27,948 22,555 22,024 24,237 25,042 24,686 17,515 Provision for income taxes 6,510 7,367 5,496 5,931 6,814 6,407 6,498 4,680 Net Income Available to Common Shareholders $ 17,659 $ 20,581 $ 17,059 $ 16,093 $ 17,423 $ 18,635 $ 18,188 $ 12,835 Per Share Data Common earnings per share—diluted $ 0.51 $ 0.59 $ 0.49 $ 0.46 $ 0.50 $ 0.54 $ 0.52 $ 0.41 Dividends declared per common share 0.20 0.19 0.19 0.19 0.19 0.18 0.18 0.18 Common book value 24.12 24.02 23.63 23.23 22.76 22.63 22.15 21.91

Summary of Significant Accoun35

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Nature of Operations	Nature of Operations S&T Bancorp, Inc., or S&T, was incorporated on March 17, 1983 under the laws of the Commonwealth of Pennsylvania as a bank holding company and has three wholly owned subsidiaries, S&T Bank, 9th Street Holdings, Inc. and STBA Capital Trust I. We own a 50 percent interest in Commonwealth Trust Credit Life Insurance Company, or CTCLIC. We are presently engaged in nonbanking activities through the following five entities: 9th Street Holdings, Inc.; S&T Bancholdings, Inc.; CTCLIC; S&T Insurance Group, LLC and Stewart Capital Advisors, LLC. 9th Street Holdings, Inc. and S&T Bancholdings, Inc. are investment holding companies. CTCLIC, which is a joint venture with another financial institution, acts as a reinsurer of credit life, accident and health insurance policies sold by S&T Bank and the other institution. S&T Insurance Group, LLC, through its subsidiaries, offers a variety of insurance products. Stewart Capital Advisors, LLC is a registered investment advisor that manages private investment accounts for individuals and institutions. On October 29, 2014, S&T and Integrity Bancshares, Inc., or Integrity, based in Camp Hill, Pennsylvania, entered into an agreement to acquire Integrity Bancshares, Inc. and the transaction was completed on March 4, 2015. Integrity Bank was subsequently merged into S&T Bank on May 8, 2015. S&T Bank is operating under the name "Integrity Bank - A Division of S&T Bank" in south-central Pennsylvania.
Accounting Policies	Accounting Policies Our financial statements have been prepared in accordance with U.S. generally accepted accounting principles, or GAAP. In preparing the financial statements, management is required to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities as of the dates of the balance sheets and revenues and expenses for the periods then ended. Actual results could differ from those estimates. Our significant accounting policies are described below.
Principles of Consolidation	Principles of Consolidation The Consolidated Financial Statements include the accounts of S&T and its wholly owned subsidiaries. All significant intercompany transactions have been eliminated in consolidation. Investments of 20 percent to 50 percent of the outstanding common stock of investees are accounted for using the equity method of accounting.
Reclassification	Reclassification Amounts in prior years' period financial statements and footnotes are reclassified whenever necessary to conform to the current year’s presentation. Reclassifications had no effect on our results of operations or financial condition.
Business Combinations	Business Combinations We account for business combinations using the acquisition method of accounting. Under this method of accounting, the acquired company’s net assets are recorded at fair value at the date of acquisition, and the results of operations of the acquired company are combined with our results from that date forward. Acquisition costs are expensed when incurred. The difference between the purchase price and the fair value of the net assets acquired (including identified intangibles) is recorded as goodwill.
Fair Value Measurements	Fair Value Measurements We use fair value measurements when recording and disclosing certain financial assets and liabilities. Securities available-for-sale, trading assets and derivative financial instruments are recorded at fair value on a recurring basis. Additionally, from time to time, we may be required to record other assets at fair value on a nonrecurring basis, such as loans held for sale, impaired loans, other real estate owned, or OREO, and other repossessed assets, mortgage servicing rights, or MSRs, and certain other assets. Fair value is the price that would be received to sell an asset or paid to transfer a liability in the principal or most advantageous market in an orderly transaction between market participants at the measurement date. An orderly transaction is a transaction that assumes exposure to the market for a period prior to the measurement date to allow for marketing activities that are usual and customary for transactions involving such assets or liabilities; it is not a forced transaction. In determining fair value, we use various valuation approaches, including market, income and cost approaches. The fair value standard establishes a hierarchy for inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that observable inputs be used when available. Observable inputs are inputs that market participants would use in pricing an asset or liability, which are developed based on market data we have obtained from independent sources. Unobservable inputs reflect our estimates of assumptions that market participants would use in pricing an asset or liability, which are developed based on the best information available in the circumstances. The fair value hierarchy gives the highest priority to unadjusted quoted market prices in active markets for identical assets or liabilities (Level 1 measurement) and the lowest priority to unobservable inputs (Level 3 measurement). The fair value hierarchy is broken down into three levels based on the reliability of inputs as follows: Level 1: valuation is based upon unadjusted quoted market prices for identical instruments traded in active markets. Level 2: valuation is based upon quoted market prices for similar instruments traded in active markets, quoted market prices for identical or similar instruments traded in markets that are not active and model-based valuation techniques for which all significant assumptions are observable in the market or can be corroborated by market data. Level 3: valuation is derived from other valuation methodologies, including discounted cash flow models and similar techniques that use significant assumptions not observable in the market. These unobservable assumptions reflect estimates of assumptions that market participants would use in determining fair value. A financial instrument’s level within the fair value hierarchy is based on the lowest level of input that is significant to the fair value measurement. Our policy is to recognize transfers between any of the fair value hierarchy levels at the end of the reporting period in which the transfer occurred. The following are descriptions of the valuation methodologies that we use for financial instruments recorded at fair value on either a recurring or nonrecurring basis. Recurring Basis Securities Available-for-Sale Securities available-for-sale include both debt and equity securities. We obtain fair values for debt securities from a third-party pricing service which utilizes several sources for valuing fixed-income securities. We validate prices received from our pricing service through comparison to a secondary pricing service and broker quotes. We review the methodologies of the pricing service which provides us with a sufficient understanding of the valuation models, assumptions, inputs and pricing to reasonably measure the fair value of our debt securities. The market evaluation sources for debt securities include observable inputs rather than significant unobservable inputs and are classified as Level 2. The service provider utilizes pricing models that vary by asset class and include available trade, bid and other market information. Generally, the methodologies include broker quotes, proprietary models, and vast descriptive terms and conditions databases, and extensive quality control programs. Marketable equity securities that have an active, quotable market are classified as Level 1. Marketable equity securities that are quotable, but are thinly traded or inactive, are classified as Level 2. Marketable equity securities that are not readily traded and do not have a quotable market are classified as Level 3. Trading Assets We use quoted market prices to determine the fair value of our trading assets. Our trading assets are held in a Rabbi Trust under a deferred compensation plan and are invested in readily quoted mutual funds. Accordingly, these assets are classified as Level 1. Derivative Financial Instruments We use derivative instruments, including interest rate swaps for commercial loans with our customers, interest rate lock commitments and the sale of mortgage loans in the secondary market. We calculate the fair value for derivatives using widely accepted valuation techniques, including discounted cash flow analysis on the expected cash flows of each derivative. Each valuation considers the contractual terms of the derivative, including the period to maturity, and uses observable market based inputs, such as interest rate curves and implied volatilities. Accordingly, derivatives are classified as Level 2. We incorporate credit valuation adjustments into the valuation models to appropriately reflect both our own nonperformance risk and the respective counterparties’ nonperformance risk in calculating fair value measurements. In adjusting the fair value of our derivative contracts for the effect of nonperformance risk, we have considered the impact of netting and any applicable credit enhancements and collateral postings. Nonrecurring Basis Loans Held for Sale Loans held for sale consist of 1-4 family residential loans originated for sale in the secondary market and, from time to time, certain loans transferred from the loan portfolio to loans held for sale, all of which are carried at the lower of cost or fair value. The fair value of 1-4 family residential loans is based on the principal or most advantageous market currently offered for similar loans using observable market data. The fair value of the loans transferred from the loan portfolio is based on the amounts offered for these loans in currently pending sales transactions. Loans held for sale carried at fair value are classified as Level 3. Impaired Loans Impaired loans are carried at the lower of carrying value or fair value. Fair value is determined as the recorded investment balance less any specific reserve. We establish specific reserves based on the following three impairment methods: 1) the present value of expected future cash flows discounted at the loan’s original effective interest rate; 2) the loan’s observable market price; or 3) the fair value of the collateral less estimated selling costs when the loan is collateral dependent and we expect to liquidate the collateral. However, if repayment is expected to come from the operation of the collateral, rather than liquidation, then we do not consider estimated selling costs in determining the fair value of the collateral. Collateral values are generally based upon appraisals by approved, independent state certified appraisers. Appraisals may be discounted based on our historical knowledge, changes in market conditions from the time of appraisal or our knowledge of the borrower and the borrower’s business. Impaired loans carried at fair value are classified as Level 3. OREO and Other Repossessed Assets OREO and other repossessed assets obtained in partial or total satisfaction of a loan are recorded at the lower of recorded investment in the loan or fair value less cost to sell. Subsequent to foreclosure, these assets are carried at the lower of the amount recorded at acquisition date or fair value less cost to sell. Accordingly, it may be necessary to record nonrecurring fair value adjustments. Fair value, when recorded, is generally based upon appraisals by approved, independent state certified appraisers. Like impaired loans, appraisals on OREO may be discounted based on our historical knowledge, changes in market conditions from the time of appraisal or other information available to us. OREO and other repossessed assets carried at fair value are classified as Level 3. Mortgage Servicing Rights The fair value of MSRs is determined by calculating the present value of estimated future net servicing cash flows, considering expected mortgage loan prepayment rates, discount rates, servicing costs and other economic factors, which are determined based on current market conditions. The expected rate of mortgage loan prepayments is the most significant factor driving the value of MSRs. MSRs are considered impaired if the carrying value exceeds fair value. The valuation model includes significant unobservable inputs; therefore, MSRs are classified as Level 3. Other Assets We measure certain other assets at fair value on a nonrecurring basis. Fair value is based on the application of lower of cost or fair value accounting, or write-downs of individual assets. Valuation methodologies used to measure fair value are consistent with overall principles of fair value accounting and consistent with those described above. Financial Instruments In addition to financial instruments recorded at fair value in our financial statements, fair value accounting guidance requires disclosure of the fair value of all of an entity’s assets and liabilities that are considered financial instruments. The majority of our assets and liabilities are considered financial instruments. Many of these instruments lack an available trading market as characterized by a willing buyer and willing seller engaged in an exchange transaction. Also, it is our general practice and intent to hold our financial instruments to maturity and to not engage in trading or sales activities with respect to such financial instruments. For fair value disclosure purposes, we substantially utilize the fair value measurement criteria as required and explained above. In cases where quoted fair values are not available, we use present value methods to determine the fair value of our financial instruments. Cash and Cash Equivalents The carrying amounts reported in the Consolidated Balance Sheets for cash and due from banks, including interest-bearing deposits, approximate fair value. Loans The fair value of variable rate performing loans that may reprice frequently at short-term market rates is based on carrying values adjusted for credit risk. The fair value of variable rate performing loans that reprice at intervals of one year or longer, such as adjustable rate mortgage products, is estimated using discounted cash flow analyses that utilize interest rates currently being offered for similar loans and adjusted for credit risk. The fair value of fixed rate performing loans is estimated using a discounted cash flow analysis that utilizes interest rates currently being offered for similar loans and adjusted for credit risk. The fair value of nonperforming loans is the carrying value less any specific reserve on the loan if it is impaired. The carrying amount of accrued interest approximates fair value. Bank Owned Life Insurance Fair value approximates net cash surrender value of bank owned life insurance, or BOLI. Federal Home Loan Bank, or FHLB, and Other Restricted Stock It is not practical to determine the fair value of our FHLB and other restricted stock due to the restrictions placed on the transferability of these stocks; it is presented at carrying value. Deposits The fair values disclosed for deposits without defined maturities (e.g., noninterest and interest-bearing demand, money market and savings accounts) are by definition equal to the amounts payable on demand. The carrying amounts for variable rate, fixed-term time deposits approximate their fair values. Estimated fair values for fixed rate and other time deposits are based on discounted cash flow analysis using interest rates currently offered for time deposits with similar terms. The carrying amount of accrued interest approximates fair value. Short-Term Borrowings The carrying amounts of securities sold under repurchase agreements, or REPOs, and other short-term borrowings approximate their fair values. Long-Term Borrowings The fair values disclosed for fixed rate long-term borrowings are determined by discounting their contractual cash flows using current interest rates for long-term borrowings of similar remaining maturities. The carrying amounts of variable rate long-term borrowings approximate their fair values. Junior Subordinated Debt Securities The interest rate on the variable rate junior subordinated debt securities is reset quarterly; therefore, the carrying values approximate their fair values. Loan Commitments and Standby Letters of Credit Off-balance sheet financial instruments consist of commitments to extend credit and letters of credit. Except for interest rate lock commitments, estimates of the fair value of these off-balance sheet items are not made because of the short-term nature of these arrangements and the credit standing of the counterparties. Other Estimates of fair value are not made for items that are not defined as financial instruments, including such items as our core deposit intangibles and the value of our trust operations.
Cash and Cash Equivalents	Cash and Cash Equivalents We consider cash and due from banks, interest-bearing deposits with banks and federal funds sold as cash and cash equivalents.
Securities	Securities We determine the appropriate classification of securities at the time of purchase. All securities, including both debt and equity securities, are classified as available-for-sale. These are securities that we intend to hold for an indefinite period of time, but that may be sold in response to changes in interest rates, prepayment risk, liquidity needs or other factors. Such securities are carried at fair value with net unrealized gains and losses deemed to be temporary and reported as a component of other comprehensive income (loss), net of tax. Realized gains and losses on the sale of available-for-sale securities and other-than-temporary impairment, or OTTI, charges are recorded within noninterest income in the Consolidated Statements of Net Income. Realized gains and losses on the sale of securities are determined using the specific-identification method. Bond premiums are amortized to the call date and bond discounts are accreted to the maturity date, both on a level yield basis. An investment security is considered impaired if its fair value is less than its cost or amortized cost basis. We perform a quarterly review of our securities to identify those that may indicate an OTTI. Our policy for OTTI within the marketable equity securities portfolio generally requires an impairment charge when the security is in a loss position for 12 consecutive months, unless facts and circumstances would suggest the need for an OTTI prior to that time. Our policy for OTTI within the debt securities portfolio is based upon a number of factors, including but not limited to, the length of time and extent to which the estimated fair value has been less than cost, the financial condition of the underlying issuer, the ability of the issuer to meet contractual obligations, the best estimate of the impairment charge representing credit losses, the likelihood of the security’s ability to recover any decline in its estimated fair value and whether management intends to sell the security or if it is more likely than not that management will be required to sell the investment security prior to the security’s recovery of any decline in its estimated fair value. If the impairment is considered other-than-temporary based on management’s review, the impairment must be separated into credit and non-credit components. The credit component is recognized in the Consolidated Statements of Net Income and the non-credit component is recognized in other comprehensive income (loss), net of applicable taxes.
Loans Held for Sale	Loans Held for Sale Loans held for sale consist of 1-4 family residential loans originated for sale in the secondary market and, from time to time, certain loans transferred from the loan portfolio to loans held for sale, all of which are carried at the lower of cost or fair value. If a loan is transferred from the loan portfolio to the held for sale category, any write-down in the carrying amount of the loan at the date of transfer is recorded as a charge-off against the allowance for loan losses, or ALL. Subsequent declines in fair value are recognized as a charge to noninterest income. When a loan is placed in the held for sale category, we stop amortizing the related deferred fees and costs. The remaining unamortized fees and costs are recognized as part of the cost basis of the loan at the time it is sold. Gains and losses on sales of loans held for sale are included in other noninterest income in the Consolidated Statements of Net Income.
Loans	Loans Loans are reported at the principal amount outstanding net of unearned income, unamortized premiums or discounts and deferred origination fees and costs. We defer certain nonrefundable loan origination and commitment fees. Accretion of discounts and amortization of premiums on loans are included in interest income in the Consolidated Statements of Net Income. Loan origination fees and direct loan origination costs are deferred and amortized as an adjustment of loan yield over the respective lives of the loans without consideration of anticipated prepayments. If a loan is paid off, the remaining unaccreted or unamortized net origination fees and costs are immediately recognized into income or expense. Interest is accrued and interest income is recognized on loans as earned. Acquired loans are recorded at fair value on the date of acquisition with no carryover of the related ALL. Determining the fair value of the acquired loans involves estimating the principal and interest cash flows expected to be collected on the loans and discounting those cash flows at a market rate of interest. In estimating the fair value of our acquired loans, we consider a number of factors including the loan term, internal risk rating, delinquency status, prepayment rates, recovery periods, estimated value of the underlying collateral and the current interest rate environment. Closed-end installment loans, amortizing loans secured by real estate and any other loans with payments scheduled monthly are reported past due when the borrower is in arrears two or more monthly payments. Other multi-payment obligations with payments scheduled other than monthly are reported past due when one scheduled payment is due and unpaid for 30 days or more. Generally, consumer loans are charged off against the ALL upon the loan reaching 90 days past due. Commercial loans are charged off as management becomes aware of facts and circumstances that raise doubt as to the collectability of all or a portion of the principal and when we believe a confirmed loss exists.
Nonaccrual or Nonperforming Loans	Nonaccrual or Nonperforming Loans We stop accruing interest on a loan when the borrower’s payment is 90 days past due. Loans are also placed on nonaccrual status when we have doubt about the borrower’s ability to comply with contractual repayment terms, even if payment is not past due. When the interest accrual is discontinued, all unpaid accrued interest is reversed against interest income. Interest income is recognized on nonaccrual loans on a cash basis if recovery of the remaining principal is reasonably assured. As a general rule, a nonaccrual loan may be restored to accrual status when its principal and interest is paid current and the bank expects repayment of the remaining contractual principal and interest, or when the loan otherwise becomes well secured and in the process of collection.
Troubled Debt Restructurings	Troubled Debt Restructurings Troubled debt restructurings, or TDRs, are loans where we, for economic or legal reasons related to a borrower’s financial difficulties, grant a concession to the borrower. We strive to identify borrowers with financial difficulty early and work with them to come to a mutual resolution to modify the terms of their loan before the loan reaches nonaccrual status. These modified terms generally include extensions of maturity dates at a stated interest rate lower than the current market rate for a new loan with similar risk characteristics, reductions in contractual interest rates or principal deferment. While unusual, there may be instances of principal forgiveness. These modifications are generally for longer term periods that would not be considered insignificant. Additionally, we classify loans where the debt obligation has been discharged through a Chapter 7 Bankruptcy and not reaffirmed as TDRs. We individually evaluate all substandard commercial loans that have experienced a forbearance or change in terms agreement, and all substandard consumer and residential mortgage loans that entered into an agreement to modify their existing loan, to determine if they should be designated as TDRs. All TDRs are considered to be impaired loans and will be reported as impaired loans for the remaining life of the loan, unless the restructuring agreement specifies an interest rate equal to or greater than the rate that would be accepted at the time of the restructuring for a new loan with comparable risk and it is fully expected that the remaining principal and interest will be collected according to the restructured agreement. Further, all impaired loans are reported as nonaccrual loans unless the loan is a TDR that has met the requirements to be returned to accruing status. TDRs can be returned to accruing status if the ultimate collectability of all contractual amounts due, according to the restructured agreement, is not in doubt and there is a period of a minimum of six months of satisfactory payment performance by the borrower either immediately before or after the restructuring.
Allowance for Loan Losses	Allowance for Loan Losses The ALL reflects our estimates of probable losses inherent in the loan portfolio at the balance sheet date. The methodology for determining the ALL has two main components: evaluation and impairment tests of individual loans and evaluation and impairment tests of certain groups of homogeneous loans with similar risk characteristics. Loans are considered to be impaired when based upon current information and events it is probable that we will be unable to collect all principal and interest payments due according to the original contractual terms of the loan agreement. We individually evaluate all substandard and nonaccrual commercial loans greater than $0.5 million for impairment. All TDRs will be reported as an impaired loan for the remaining life of the loan, unless the restructuring agreement specifies an interest rate equal to or greater than the rate that would be accepted at the time of the restructuring for a new loan with comparable risk and it is fully expected that the remaining principal and interest will be fully collected according to the restructured agreement. For all TDRs, regardless of size, and all other impaired loans, we conduct further analysis to determine the probable loss and assign a specific reserve to the loan if deemed appropriate. Specific reserves are established based upon the following three impairment methods: 1) the present value of expected future cash flows discounted at the loan’s original effective interest rate, 2) the loan’s observable market price or 3) the estimated fair value of the collateral if the loan is collateral dependent. Our impairment evaluations consist primarily of the fair value of collateral method because most of our loans are collateral dependent. Collateral values are discounted to consider disposition costs when appropriate. A specific reserve is established or a charge-off is taken if the fair value of the impaired loan is less than the recorded investment in the loan balance. The ALL for homogeneous loans is calculated using a systematic methodology with both a quantitative and a qualitative analysis that is applied on a quarterly basis. The ALL model is comprised of five distinct portfolio segments: 1) Commercial Real Estate, or CRE, 2) Commercial and Industrial, or C&I, 3) Commercial Construction, 4) Consumer Real Estate and 5) Other Consumer. Each segment has a distinct set of risk characteristics monitored by management. We further assess and monitor risk and performance at a more disaggregated level which includes our internal risk rating system for the commercial segments and type of collateral, lien position and loan-to-value, or LTV, for the consumer segments. We first apply historical loss rates to pools of loans with similar risk characteristics. Loss rates are calculated by historical charge-offs that have occurred within each pool of loans over the loss emergence period, or LEP. The LEP is an estimate of the average amount of time from when an event happens that causes the borrower to be unable to pay on a loan until the loss is confirmed through a loan charge-off. In conjunction with our annual review of the ALL assumptions, we have updated our analysis of LEPs for our Commercial and Consumer loan portfolio segments using our loan charge-off history. The analysis showed that the LEP for our Commercial Real Estate, or CRE, and Commercial and Industrial, or C&I portfolios, have shortened and the LEP for our Commercial Construction portfolio segment has lengthened. We estimate the LEP to be 3 years for CRE and 4 years for construction compared to 3.5 years for both in the prior year and 1.25 years for C&I compared to 2.5 years in the prior year. Our analysis showed an LEP for Consumer Real Estate of 2.75 years compared to 3.5 years in the prior year and Other Consumer of 1.25 years which is consistent with the prior year. Another key assumption is the look-back period, or LBP, which represents the historical data period utilized to calculate loss rates. During 2016, we lengthened the LBP for all Commercial and Consumer portfolio segments in order to capture relevant historical data believed to be reflective of losses inherent in the portfolios. We used 7.5 years for our LBP for all portfolio segments which encompasses our loss experience during the recession, and our more recent improved loss experience. This compared to a LBP of 6.5 years in the prior year. The changes made to the ALL assumptions were applied prospectively and did not result in a material change to the total ALL. After consideration of the historic loss calculations, management applies additional qualitative adjustments so that the ALL is reflective of the inherent losses that exist in the loan portfolio at the balance sheet date. Qualitative adjustments are made based upon changes in lending policies and practices, economic conditions, changes in the loan portfolio, changes in lending management, results of internal loan reviews, asset quality trends, collateral values, concentrations of credit risk and other external factors. The evaluation of the various components of the ALL requires considerable judgment in order to estimate inherent loss exposures. Acquired loans are recorded at fair value on the date of acquisition with no carryover of the related ALL. Determining the fair value of acquired loans involves estimating the principal and interest cash flows expected to be collected on the loans and discounting those cash flows at a market rate of interest. In estimating the fair value of our acquired loans, we considered a number of factors including the loan term, internal risk rating, delinquency status, prepayment rates, recovery periods, estimated value of the underlying collateral and the current interest rate environment. Loans acquired with evidence of credit deterioration were evaluated and not considered to be significant. The premium or discount estimated through the loan fair value calculation is recognized into interest income on a level yield or straight-line basis over the remaining contractual life of the loans. Additional credit deterioration on acquired loans, in excess of the original credit discount embedded in the fair value determination on the date of acquisition, will be recognized in the ALL through the provision for loan losses. Our ALL Committee meets quarterly to verify the overall adequacy of the ALL. Additionally, on an annual basis, the ALL Committee meets to validate our ALL methodology. This validation includes reviewing the loan segmentation, LEP, LBP and the qualitative framework. As a result of this ongoing monitoring process, we may make changes to our ALL to be responsive to the economic environment. Although we believe our process for determining the ALL adequately considers all of the factors that would likely result in credit losses, the process includes subjective elements and may be susceptible to significant change. To the extent actual losses are higher than management estimates, additional provisions for loan losses could be required and could adversely affect our earnings or financial position in future periods.
Bank Owned Life Insurance	Bank Owned Life Insurance We have purchased life insurance policies on certain executive officers and employees. We receive the cash surrender value of each policy upon its termination or benefits are payable upon the death of the insured. Changes in net cash surrender value are recognized in noninterest income or expense in the Consolidated Statements of Net Income.
Premises and Equipment	Premises and Equipment Premises and equipment, including leasehold improvements, are stated at cost less accumulated depreciation. Maintenance and repairs are charged to expense as incurred, while improvements that extend an asset’s useful life are capitalized and depreciated over the estimated remaining life of the asset. Depreciation expense is computed by the straight-line method for financial reporting purposes and accelerated methods for income tax purposes over the estimated useful lives of the particular assets. Management reviews long-lived assets using events and circumstances to determine if and when an asset is evaluated for recoverability. The estimated useful lives for the various asset categories are as follows: 1) Land and Land Improvements Non-depreciating assets 2) Buildings 25 years 3) Furniture and Fixtures 5 years 4) Computer Equipment and Software 5 years or term of license 5) Other Equipment 5 years 6) Vehicles 5 years 7) Leasehold Improvements Lesser of estimated useful life of the asset (generally 15 years unless established otherwise) or the remaining term of the lease, including renewal options in the lease that are reasonably assured of exercise
Restricted Investment in Bank Stock	Restricted Investment in Bank Stock Federal Home Loan Bank, or FHLB, stock is carried at cost and evaluated for impairment based on the ultimate recoverability of the par value. We hold FHLB stock because we are a member of the FHLB of Pittsburgh. The FHLB requires members to purchase and hold a specified level of FHLB stock based upon on the member's asset value, level of borrowings and participation in other programs offered. Stock in the FHLB is non-marketable and is redeemable at the discretion of the FHLB. Members do not purchase stock in the FHLB for the same reasons that traditional equity investors acquire stock in an investor-owned enterprise. Rather, members purchase stock to obtain access to the low-cost products and services offered by the FHLB. Unlike equity securities of traditional for-profit enterprises, the stock of the FHLB does not provide its holders with an opportunity for capital appreciation because, by regulation, FHLB stock can only be purchased, redeemed and transferred at par value. Both cash and stock dividends are reported as income in taxable investment securities in the Consolidated Statements of Net Income. FHLB stock is evaluated for OTTI on a quarterly basis. Atlantic Community Bankers’ Bank, or ACBB, stock is carried at cost and evaluated for impairment based on the ultimate recoverability of the carrying value. We do not currently use their membership products and services. We acquired ACBB stock through various mergers of banks that were ACBB members. ACBB stock is evaluated for OTTI on a quarterly basis.
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets We have three reporting units: Community Banking, Insurance and Wealth Management. At December 31, 2016, we had goodwill of $291.7 million , including $287.4 million in Community Banking, representing 99 percent of total goodwill, and $4.2 million in Insurance, representing one percent of total goodwill. The carrying value of goodwill is tested annually for impairment each October 1 or more frequently if it is determined that we should do so. We first assess qualitatively whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount. Our qualitative assessment considers such factors as macroeconomic conditions, market conditions specifically related to the banking industry, our overall financial performance and various other factors. If we determine that it is more likely than not that the fair value is less than the carrying amount, we proceed to test for impairment. The evaluation for impairment involves comparing the current estimated fair value of each reporting unit to its carrying value, including goodwill. If the current estimated fair value of a reporting unit exceeds its carrying value, no additional testing is required and impairment loss is not recorded. If the estimated fair value of a reporting unit is less than the carrying value, further valuation procedures are performed and could result in impairment of goodwill being recorded. Further valuation procedures would include allocating the estimated fair value to all assets and liabilities of the reporting unit to determine an implied goodwill value. If the implied value of goodwill of a reporting unit is less than the carrying amount of that goodwill, an impairment loss is recognized in an amount equal to that excess. We have core deposit and other intangible assets resulting from acquisitions which are subject to amortization. We determine the amount of identifiable intangible assets based upon independent core deposit and insurance contract analyses at the time of the acquisition. Intangible assets with finite useful lives, consisting primarily of core deposit and customer list intangibles, are amortized using straight-line or accelerated methods over their estimated weighted average useful lives, ranging from 10 to 20 years. Intangible assets with finite useful lives are evaluated for impairment whenever events or changes in circumstances indicate that their carrying amount may not be recoverable.
Variable Interest Entities	Variable Interest Entities Variable interest entities, or VIEs, are legal entities that generally either do not have equity investors with voting rights or that have equity investors that do not provide sufficient financial resources for the entity to support its activities. When an enterprise has both the power to direct the economic activities of the VIE and the obligation to absorb losses of the VIE or the right to receive benefits of the VIE, the entity has a controlling financial interest in the VIE. A VIE often holds financial assets, including loans or receivables, or other property. The company with a controlling financial interest, the primary beneficiary, is required to consolidate the VIE into its consolidated balance sheets. S&T has one wholly-owned trust subsidiary, STBA Capital Trust I, or the Trust, for which it does not absorb a majority of expected losses or receive a majority of the expected residual returns. At its inception in 2008, the Trust issued floating rate trust preferred securities to the Trustee, another financial institution, and used the proceeds from the sale to invest in junior subordinated debt issued by us, which is the sole asset of the Trust. The Trust pays dividends on the trust preferred securities at the same rate as the interest we pay on our junior subordinated debt held by the Trust. Because the third-party investors are the primary beneficiaries, the Trust qualifies as a VIE. Accordingly, the Trust and its net assets are not included in our Consolidated Financial Statements. However, the junior subordinated debt issued by S&T is included in our Consolidated Balance Sheets.
Joint Ventures	Joint Ventures We have made investments directly in Low Income Housing Tax Credit, or LIHTC, partnerships formed with third parties. As a limited partner in these operating partnerships, we receive tax credits and tax deductions for losses incurred by the underlying properties. These investments are amortized over a maximum of 10 years , which represents the period over which the tax credits will be utilized. We have determined that we are not the primary beneficiary of these investments because the general partners have the power to direct the activities that most significantly impact the economic performance of the partnership and have both the obligation to absorb expected losses and the right to receive benefits.
OREO and Other Repossessed Assets	OREO and Other Repossessed Assets OREO and other repossessed assets are included in other assets in the Consolidated Balance Sheets and are comprised of properties acquired through foreclosure proceedings or acceptance of a deed in lieu of a foreclosure. At the time of foreclosure or acceptance of a deed in lieu of foreclosure, these properties are recorded at the lower of the recorded investment in the loan or fair value less cost to sell. Loan losses arising from the acquisition of any such property initially are charged against the ALL. Subsequently, these assets are carried at the lower of carrying value or current fair value less cost to sell. Gains or losses realized upon disposition of these assets are recorded in other expenses in the Consolidated Statements of Net Income.
Mortgage Servicing Rights	Mortgage Servicing Rights MSRs are recognized as separate assets when commitments to fund a loan to be sold are made. Upon commitment, the MSR is established, which represents the then current estimated fair value of future net cash flows expected to be realized for performing the servicing activities. The estimated fair value of the MSRs is estimated by calculating the present value of estimated future net servicing cash flows, considering expected mortgage loan prepayment rates, discount rates, servicing costs and other economic factors, which are determined based on current market conditions. The expected rate of mortgage loan prepayments is the most significant factor driving the value of MSRs. Increases in mortgage loan prepayments reduce estimated future net servicing cash flows because the life of the underlying loan is reduced. In determining the estimated fair value of MSRs, mortgage interest rates, which are used to determine prepayment rates, are held constant over the estimated life of the portfolio. MSRs are reported in other assets in the Consolidated Balance Sheets and are amortized into noninterest income in the Consolidated Statements of Net Income in proportion to, and over the period of, the estimated future net servicing income of the underlying mortgage loans. MSRs are regularly evaluated for impairment based on the estimated fair value of those rights. MSRs are stratified by certain risk characteristics, primarily loan term and note rate. If temporary impairment exists within a risk stratification tranche, a valuation allowance is established through a charge to income equal to the amount by which the carrying value exceeds the estimated fair value. If it is later determined that all or a portion of the temporary impairment no longer exists for a particular tranche, the valuation allowance is reduced. MSRs are also reviewed for OTTI. OTTI exists when the recoverability of a recorded valuation allowance is determined to be remote, taking into consideration historical and projected interest rates and loan pay-off activity. When this situation occurs, the unrecoverable portion of the valuation allowance is applied as a direct write-down to the carrying value of the MSR. Unlike a valuation allowance, a direct write-down permanently reduces the carrying value of the MSR and the valuation allowance, precluding subsequent recoveries.
Derivative Financial Instruments	Derivative Financial Instruments Interest Rate Swaps In accordance with applicable accounting guidance for derivatives and hedging, all derivatives are recognized as either assets or liabilities on the balance sheet at fair value. Interest rate swaps are contracts in which a series of interest rate flows (fixed and variable) are exchanged over a prescribed period. The notional amounts on which the interest payments are based are not exchanged. These derivative positions relate to transactions in which we enter into an interest rate swap with a commercial customer while at the same time entering into an offsetting interest rate swap with another financial institution. In connection with each transaction, we agree to pay interest to the customer on a notional amount at a variable interest rate and receive interest from the customer on a same notional amount at a fixed rate. At the same time, we agree to pay another financial institution the same fixed interest rate on the same notional amount and receive the same variable interest rate on the same notional amount. The transaction allows our customer to effectively convert a variable rate loan to a fixed rate loan with us receiving a variable rate. These agreements could have floors or caps on the contracted interest rates. Pursuant to our agreements with various financial institutions, we may receive collateral or may be required to post collateral based upon mark-to-market positions. Beyond unsecured threshold levels, collateral in the form of cash or securities may be made available to counterparties of interest rate swap transactions. Based upon our current positions and related future collateral requirements relating to them, we believe any effect on our cash flow or liquidity position to be immaterial. Derivatives contain an element of credit risk, the possibility that we will incur a loss because a counterparty, which may be a financial institution or a customer, fails to meet its contractual obligations. All derivative contracts with financial institutions may be executed only with counterparties approved by our Asset and Liability Committee, or ALCO, and derivatives with customers may only be executed with customers within credit exposure limits approved by our Senior Loan Committee. Interest rate swaps are considered derivatives, but are not accounted for using hedge accounting. As such, changes in the estimated fair value of the derivatives are recorded in current earnings and included in other noninterest income in the Consolidated Statements of Net Income. Interest Rate Lock Commitments and Forward Sale Contracts In the normal course of business, we sell originated mortgage loans into the secondary mortgage loan market. We also offer interest rate lock commitments to potential borrowers. The commitments are generally for a period of 60 days and guarantee a specified interest rate for a loan if underwriting standards are met, but the commitment does not obligate the potential borrower to close on the loan. Accordingly, some commitments expire prior to becoming loans. We can encounter pricing risks if interest rates increase significantly before the loan can be closed and sold. We may utilize forward sale contracts in order to mitigate this pricing risk. Whenever a customer desires these products, a mortgage originator quotes a secondary market rate guaranteed for that day by the investor. The rate lock is executed between the mortgagee and us and in turn a forward sale contract may be executed between us and the investor. Both the rate lock commitment and the corresponding forward sale contract for each customer are considered derivatives, but are not accounted for using hedge accounting. As such, changes in the estimated fair value of the derivatives during the commitment period are recorded in current earnings and included in mortgage banking in the Consolidated Statements of Net Income.
Allowance for Unfunded Commitments	Allowance for Unfunded Commitments In the normal course of business, we offer off-balance sheet credit arrangements to enable our customers to meet their financing objectives. These instruments involve, to varying degrees, elements of credit and interest rate risk in excess of the amount recognized in the financial statements. Our exposure to credit loss, in the event the customer does not satisfy the terms of the agreement, equals the contractual amount of the obligation less the value of any collateral. We apply the same credit policies in making commitments and standby letters of credit that are used for the underwriting of loans to customers. Commitments generally have fixed expiration dates, annual renewals or other termination clauses and may require payment of a fee. Because many of the commitments are expected to expire without being drawn upon, the total commitment amounts do not necessarily represent future cash requirements. The allowance for unfunded commitments is included in other liabilities in the Consolidated Balance Sheets. The allowance for unfunded commitments is determined using a similar methodology as our ALL methodology.
Treasury Stock	Treasury Stock The repurchase of our common stock is recorded at cost. At the time of reissuance, the treasury stock account is reduced using the average cost method. Gains and losses on the reissuance of common stock are recorded in additional paid-in capital, to the extent additional paid-in capital from previous treasury share transactions exists. Any deficiency is charged to retained earnings.
Revenue Recognition	Revenue Recognition We recognize revenues as they are earned based on contractual terms or as services are provided when collectability is reasonably assured. Our principal source of revenue is interest income, which is recognized on an accrual basis. Interest and dividend income, loan fees, trust fees, fees and charges on deposit accounts, insurance commissions and other ancillary income related to our deposits and lending activities are accrued as earned.
Wealth Management Fees	Wealth Management Fees Assets held in a fiduciary capacity by our subsidiary bank, S&T Bank, are not our assets and are therefore not included in our Consolidated Financial Statements. Wealth management fee income is reported in the Consolidated Statements of Net Income on an accrual basis.
Stock-Based Compensation	Stock-Based Compensation Stock-based compensation may include stock options and restricted stock which is measured using the fair value method of accounting. The grant date fair value is recognized over the period during which the recipient is required to provide service in exchange for the award. Stock option expense is determined utilizing the Black-Scholes model. Restricted stock expense is determined using the grant date fair value. We estimate expected forfeitures when stock-based awards are granted and record compensation expense only for awards that are expected to vest.
Pensions	Pensions The expense for S&T Bank’s qualified and nonqualified defined benefit pension plans is actuarially determined using the projected unit credit actuarial cost method. It requires us to make economic assumptions regarding future interest rates and asset returns and various demographic assumptions. We estimate the discount rate used to measure benefit obligations by applying the projected cash flow for future benefit payments to a yield curve of high-quality corporate bonds available in the marketplace and by employing a model that matches bonds to our pension cash flows. The expected return on plan assets is an estimate of the long-term rate of return on plan assets, which is determined based on the current asset mix and estimates of return by asset class. We recognize in the Consolidated Balance Sheets an asset for the plan’s overfunded status or a liability for the plan’s underfunded status. Gains or losses related to changes in benefit obligations or plan assets resulting from experience different from that assumed are recognized as other comprehensive income (loss) in the period in which they occur. To the extent that such gains or losses exceed ten percent of the greater of the projected benefit obligation or plan assets, they are recognized as a component of pension costs over the future service periods of actively employed plan participants. The funding policy for the qualified plan is to contribute an amount each year that is at least equal to the minimum required contribution as determined under the Pension Protection Act of 2006 and the Bipartisan Budget Act of 2015, but not more than the maximum amount permissible for taxable plan sponsors. Our nonqualified plans are unfunded.
Marketing Costs	Marketing Costs We expense all marketing-related costs, including advertising costs, as incurred.
Income Taxes	Income Taxes We estimate income tax expense based on amounts expected to be owed to the tax jurisdictions where we conduct business. On a quarterly basis, management assesses the reasonableness of our effective tax rate based upon our current estimate of the amount and components of net income, tax credits and the applicable statutory tax rates expected for the full year. We classify interest and penalties as an element of tax expense. Deferred income tax assets and liabilities are determined using the asset and liability method and are reported in other assets or other liabilities, as appropriate, in the Consolidated Balance Sheets. Under this method, the net deferred tax asset or liability is based on the tax effects of the differences between the book and tax basis of assets and liabilities and recognizes enacted changes in tax rate and laws. When deferred tax assets are recognized, they are subject to a valuation allowance based on management’s judgment as to whether realization is more likely than not. Accrued taxes represent the net estimated amount due to taxing jurisdictions and are reported in other assets or other liabilities, as appropriate, in the Consolidated Balance Sheets. We evaluate and assess the relative risks and appropriate tax treatment of transactions and filing positions after considering statutes, regulations, judicial precedent and other information and maintain tax accruals consistent with the evaluation of these relative risks and merits. Changes to the estimate of accrued taxes occur periodically due to changes in tax rates, interpretations of tax laws, the status of examinations being conducted by taxing authorities and changes to statutory, judicial and regulatory guidance. These changes, when they occur, can affect deferred taxes and accrued taxes, and the current period’s income tax expense and can be significant to our operating results. Tax positions are recognized as a benefit only if it is “more likely than not” that the tax position would be sustained in a tax examination, with a tax examination being presumed to occur. The amount recognized is the largest amount of tax benefit that is greater than 50 percent likely of being realized on examination. For tax positions not meeting the “more likely than not” test, no tax benefit is recorded.
Earnings Per Share	Earnings Per Share Basic earnings per share, or EPS, is calculated using the two-class method to determine income allocated to common shareholders. Unvested share-based payment awards that contain nonforfeitable rights to dividends are considered participating securities under the two-class method. Income allocated to common shareholders is then divided by the weighted average number of common shares outstanding during the period. Potentially dilutive securities are excluded from the basic EPS calculation. Diluted EPS is calculated under the more dilutive of either the treasury stock method or the two-class method. Under the treasury stock method, the weighted average number of common shares outstanding is increased by the potentially dilutive common shares. For the two-class method, diluted EPS is calculated for each class of shareholders using the weighted average number of shares attributed to each class. Potentially dilutive common shares are common stock equivalents relating to our outstanding warrants, stock options and restricted stock.
Recently Adopted Accounting Standards Updates, or ASU	Recently Adopted Accounting Standards Updates, or ASU Business Combinations - Simplifying the Accounting for Measurement Period Adjustments In September 2015, the Financial Accounting Standards Board, or FASB, issued ASU No. 2015-16, Business Combinations - Simplifying the Accounting for Measurement Period Adjustments (Topic 805). The amendments in this ASU No. 2015-16 eliminate the requirement to retrospectively adjust the financial statements for measurement-period adjustments as if they were known at the acquisition date, and instead such adjustments will be recognized in the reporting period in which they are determined. Additional disclosures are required about the impact on current-period income statement line items of adjustments that would have been recognized in prior periods if that information had been revised. The measurement period is a reasonable time period after the acquisition date when the acquirer may adjust the provisional amounts recognized for a business combination if the necessary information is not available by the end of the reporting period in which the acquisition occurs. The measurement periods cannot continue for more than one year from the acquisition date. The standard is effective for annual periods and interim periods beginning after December 15, 2015. The adoption of this ASU had no impact on our results of operations or financial position. Intangibles - Goodwill and Other - Internal-Use Software: Customer's Accounting for Fees Paid in a Cloud Computing Arrangement In April 2015, the FASB issued ASU No. 2015-05, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Customer's Accounting for Fees Paid in a Cloud Computing Arrangement. The main provisions of ASU No. 2015-05 provide a basis for evaluating whether a cloud computing arrangement includes a software license. If a cloud computing arrangement includes a software license, then the customer should account for the software license element of the arrangement consistent with the acquisition of other software licenses. If a cloud computing arrangement does not include a software license, then the arrangement should be accounted for as a service contract. The standard is effective for annual periods and interim periods beginning after December 15, 2015. The adoption of this ASU had no impact on our results of operations or financial position. Interest - Imputation of Interest: Simplifying the Presentation of Debt Issuance Costs In April 2015, the FASB issued ASU No. 2015-03, Interest - Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs. The amendments in this ASU require that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. The standard is required to be adopted by public business entities in annual periods beginning on or after December 15, 2015. In September 2015, the FASB issued ASU No. 2015-15, Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements. ASU No. 2015-15 amends the SEC Content in Subtopic 835-30 by adding SEC paragraph 835-30-S35-1, Interest-Imputation of Interest Subsequent Measurement and paragraph 830-30-S45-1, Other Presentation Matters. These paragraphs were added because ASU No. 2015-03 issued in April 2015 does not address presentation or subsequent measurement of debt issuance costs related to "line-of-credit arrangements." The adoption of this ASU had no material impact on our results of operations or financial position. Consolidation: Amendments to the Consolidation Analysis In February 2015, the FASB issued ASU No. 2015-02, Consolidation (Topic 810): Amendments to the Consolidation Analysis. The amendments in this ASU affect reporting entities that are required to evaluate whether they should consolidate certain legal entities. All legal entities are subject to reevaluation under the revised consolidation model. Specifically, the amendments: 1. modify the evaluation of whether limited partnerships and similar legal entities are variable interest entities, or VIEs, or voting interest entities; 2. eliminate the presumption that a general partner should consolidate a limited partnership; 3. affect the consolidation analysis of reporting entities that are involved with VIEs, particularly those that have fee arrangements and related party relationships; and 4. provide a scope exception from consolidation guidance for reporting entities with interests in legal entities 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 for registered money market funds. The amendments in this ASU are effective for public business entities for fiscal years, and for interim periods within those fiscal years, beginning after December 15, 2015. The adoption of this ASU had no impact on our results of operations or financial position. Income Statement - Extraordinary and Unusual Items: Simplifying Income Statement Presentation by Eliminating the Concept of Extraordinary In January 2015, the FASB issued ASU No. 2015-01, Income Statement - Extraordinary and Unusual Items (Subtopic 225-20): Simplifying Income Statement Presentation by Eliminating the Concept of Extraordinary. The amendments in this ASU No. 2015-01 eliminate from GAAP the concept of extraordinary items and eliminate the requirements for reporting entities to consider whether an underlying event or transaction is extraordinary. The presentation and disclosure guidance for items that are unusual in nature or occur infrequently will be retained and will be expanded to include items that are both unusual in nature and infrequently occurring. The standard is required to be adopted by public business entities in annual periods beginning on or after December 15, 2015. The adoption of this ASU had no impact on our results of operations or financial position. Recently Issued Accounting Standards Updates not yet Adopted Income Taxes - Intra-Entity Transfers of Assets Other Than Inventory In October 2016, the FASB issued ASU No. 2016-16, Intra-Entity Transfers of Assets Other Than Inventory. The main objective of this ASU is to require companies to recognize the income tax effects of intercompany sales and transfers of assets other than inventory in the period in which the transfer occurs. This represents a change from existing guidance, which requires companies to defer the income tax effects of intercompany transfers of assets until the asset has been sold to an outside party or otherwise recognized. The new guidance will require companies to defer the income tax effects only of intercompany transfers of inventory. The ASU does not explicitly state whether the tax effects of intra-entity transfers of assets other than inventory should be recognized as discrete items or included in the estimated annual effective tax rate for interim reporting purposes. This Update is effective for annual periods beginning after December 15, 2017. Early adoption is permitted as of the beginning of an annual period. If an entity chooses to early adopt the amendments in the ASU, it must do so in the first interim period of its annual financial statements. That is, an entity cannot adopt the amendments in the ASU in a later interim period and apply them as if they were in effect as of the beginning of the year. We are evaluating the provisions of this ASU to determine the potential impact on our results of operations and financial position. Statement of Cash Flows - Classification of Certain Cash Receipts and Cash Payments In August 2016, the FASB issued ASU No. 2016-15, Classification of Certain Cash Receipts and Cash Payments. The main objective of this ASU is to reduce diversity in practice in how certain transactions are classified in the statement of cash flows. The amendments in this Update provide guidance on the following eight specific cash flow issues: Debt prepayment or debt extinguishment costs, Settlement of zero-coupon debt instruments, Contingent consideration payments made after a business combination, Proceeds from the settlement of insurance claims, Proceeds from the settlement of bank-owned life insurance (BOLI) policies, Distributions received from equity method investments, Beneficial interests in securitization transactions, and Separately identifiable cash flows and application of the predominance principle. This Update is effective for interim and annual reporting periods in fiscal years beginning after December 15, 2017. Early adoption is permitted, provided that all of the amendments are adopted in the same period. We are evaluating the provisions of this ASU to determine the potential impact on our results of operations and financial position. Financial Instruments - Credit Losses In June 2016, the FASB issued ASU No. 2016-13, Measurement of Credit Losses on Financial Instruments. The main objective of this ASU is to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments and other commitments to extend credit held by a reporting entity at each reporting date. The amendments of this update replace the incurred loss impairment methodology in current GAAP with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates. The collective changes to the recognition and measurement accounting standards for financial instruments and their anticipated impact on the allowance for credit losses modeling have been universally referred to as the CECL, or current expected credit loss, model. This Update is effective for interim and annual reporting periods in fiscal years beginning after December 15, 2019. Early adoption is permitted as of fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. We are evaluating the provisions of this ASU to determine the potential impact on our results of operations and financial position. Revenue from Contracts with Customers In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606). The new revenue pronouncement creates a single source of revenue guidance for all companies in all industries and is more principles-based than current revenue guidance. The pronouncement provides a five-step model for a company to recognize revenue when it transfers control of goods or services to customers at an amount that reflects the consideration to which it expects to be entitled in exchange for those goods or services. The five steps are: 1. identify the contract with the customer; 2. identify the separate performance obligations in the contract; 3. determine the transaction price; 4. allocate the transaction price to the separate performance obligations; and 5. recognize revenue when each performance obligation is satisfied. In August 2015, the FASB issued ASU No. 2015-14, Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date. This ASU defers the effective date of ASU No. 2014-09 for all entities by one year. In March 2016, the FASB issued ASU No. 2016-08, Principal versus Agent Considerations (Reporting Revenue Gross versus Net), as an amendment to ASU No. 2014-09 to improve Topic 606, Revenue from Contracts with Customers by reducing: 1. The potential for diversity in practice arising from inconsistent and application of the principal versus agent guidance, and 2. The cost and complexity of applying Topic 606 both at transition and on an ongoing basis. In April 2016, the FASB issued ASU No. 2016-10, Identifying Performance Obligations and Licensing, as an amendment to ASU No. 2014-09 to improve Topic 606, Revenue from Contracts with Customers, by reducing: 1. The potential for diversity in practice at initial application, and 2. The cost and complexity of applying Topic 606 both at transition and on an ongoing basis. In May 2016, the FASB issued ASU No. 2016-12, Narrow-scope Improvements and Practical Expedients. The amendments in this ASU do not change the core principles of Topic 606, Revenue from Contracts with Customers. These amendments affect only the narrow aspects of Topic 606: 1. Collectibility Criterion, 2. Presentation of Sales Taxes and Other Similar Taxes Collected from Customers, 3. Noncash Consideration, 4. Contract Modifications at Transition, and 5. Completed Contracts at Transition. ASU 2014-09, including transition requirements for all amendments, is effective for interim and annual reporting periods in fiscal years beginning after December 15, 2017. Early adoption is permitted as of the original effective date for interim and annual reporting periods in fiscal years beginning after December 15, 2016. We are evaluating the provisions of these ASUs to determine the potential impact to our results of operations and financial position. Stock Compensation - Improvements to Employee Share-Based Payment Accounting On March 31, 2016, the FASB issued ASU No. 2016-09, Improvements to Employee Share-Based Payment Accounting, which is intended to improve the accounting for share-based payment transactions as part of the FASB's simplification initiative. The ASU changes seven aspects of the accounting for share-based payment award transactions, including; 1. accounting for income taxes; 2. classification of excess tax benefits on the statement of cash flows; 3. forfeitures; 4. minimum statutory tax withholding requirements; 5. classification of employee taxes paid on the statement of cash flows when an employer withholds shares for tax-withholding purposes; 6. practical expedient -- expected term (nonpublic only); and 7. intrinsic value (nonpublic only). This ASU is effective for fiscal years beginning after December 15, 2016 and interim periods within those years for public business entities. Early adoption is permitted in any interim or annual period provided that the entire ASU is adopted. We do not expect that this ASU will have a material impact on our results of operations and financial position. Equity Method and Joint Ventures - Simplifying the Transition to the Equity Method of Accounting In March 2016, the FASB issued ASU No. 2016-07, Simplifying the Transition to the Equity Method of Accounting, which eliminates the requirement for an investor to retroactively apply the equity method when its increase in ownership interest (or degree of influence) in an investee triggers equity method accounting. This ASU is effective for annual and interim periods in fiscal years beginning after December 15, 2016. The amendments should be applied prospectively upon their effective date to increases in the level of ownership interest or degree of influence that result in the adoption of the equity method. Earlier application is permitted. We do not expect that this ASU will have a material impact on our results of operations and financial position. Leases - Section A-Amendments to the FASB Accounting Standards Codification, Section B-Conforming Amendments Related to Leases and Section C-Background Information and Basis for Conclusions In February 2016, the FASB issued ASU No. 2016-02, Leases, which requires lessees to recognize a right-to-use asset and a lease obligation for all leases on the balance sheet. Lessor accounting remains substantially similar to current GAAP. ASU 2016-02 supersedes Topic 840, Leases. This ASU is effective for annual and interim periods in fiscal years beginning after December 15, 2018. ASU 2016-02 mandates a modified retrospective transition method for all entities. Early adoption of this ASU is permitted. We anticipate that this ASU will impact our financial statements as it relates to the recognition of right-to-use assets and lease obligations on our Consolidated Balance Sheet. However, we do not expect that this ASU will have a material impact on our Consolidated Statement of Net Income. Accounting for Financial Instruments - Overall: Classification and Measurement In January 2016, the FASB issued ASU No. 2016-01, Accounting for Financial Instruments - Overall: Classification and Measurement (Subtopic 825-10). The amendments in this ASU No. 2016-01 address the following: 1. require equity investments to be measured at fair value with changes in fair value recognized in net income; 2. simplify the impairment assessment of equity investments without readily-determinable fair values by requiring a qualitative assessment to identify impairment; 3. eliminate the requirement to disclose the method(s) and significant assumptions used to estimate the fair value that is required to be disclosed for financial instruments measured at amortized cost on the balance sheet; 4. require entities to use the exit price notion when measuring the fair value of financial instruments for disclosure purposes; 5. require separate presentation in other comprehensive income for the portion of the total change in the fair value of a liability resulting from a change in the instrument-specific credit risk when the entity has elected to measure the liability at fair value in accordance with the fair value option for financial instruments; 6. require separate presentation of financial assets and financial liabilities by measurement category and form of financial asset (that is, securities or loans and receivables) on the balance sheet or the accompanying notes to the financial statements; and 7. clarify that an entity should evaluate the need for a valuation allowance on a deferred tax asset related to available-for-sale securities in combination with the entity's other deferred tax assets. This ASU is effective for annual and interim periods in fiscal years beginning after December 15, 2017. We anticipate that this ASU will have a significant impact on our financial statements and disclosures primarily as it relates to recognizing the fair value changes for equity securities in net income rather than an adjustment to equity through other comprehensive income.
Allowance for Loan Losses by Portfolio	We maintain an ALL at a level determined to be adequate to absorb estimated probable credit losses inherent in the loan portfolio as of the balance sheet date. We develop and document a systematic ALL methodology based on the following portfolio segments: 1) CRE, 2) C&I, 3) Commercial Construction, 4) Consumer Real Estate and 5) Other Consumer. The following are key risks within each portfolio segment: CRE —Loans secured by commercial purpose real estate, including both owner occupied properties and investment properties for various purposes such as hotels, strip malls and apartments. Operations of the individual projects and global cash flows of the debtors are the primary sources of repayment for these loans. The condition of the local economy is an important indicator of risk, but there are also more specific risks depending on the collateral type and the business prospects of the lessee, if the project is not owner occupied. C&I —Loans made to operating companies or manufacturers for the purpose of production, operating capacity, accounts receivable, inventory or equipment financing. Cash flow from the operations of the company is the primary source of repayment for these loans. The condition of the local economy is an important indicator of risk, but there are also more specific risks depending on the industry of the company. Collateral for these types of loans often do not have sufficient value in a distressed or liquidation scenario to satisfy the outstanding debt. Commercial Construction —Loans made to finance construction of buildings or other structures, as well as to finance the acquisition and development of raw land for various purposes. While the risk of these loans is generally confined to the construction period, if there are problems, the project may not be completed, and as such, may not provide sufficient cash flow on its own to service the debt or have sufficient value in a liquidation to cover the outstanding principal. The condition of the local economy is an important indicator of risk, but there are also more specific risks depending on the type of project and the experience and resources of the developer. Consumer Real Estate —Loans secured by first and second liens such as home equity loans, home equity lines of credit and 1-4 family residential mortgages, including purchase money mortgages. The primary source of repayment for these loans is the income and assets of the borrower. The condition of the local economy, in particular the unemployment rate, is an important indicator of risk for this segment. The state of the local housing market can also have a significant impact on this segment because low demand and/or declining home values can limit the ability of borrowers to sell a property and satisfy the debt. Other Consumer —Loans made to individuals that may be secured by assets other than 1-4 family residences, as well as unsecured loans. This segment includes auto loans, unsecured loans and lines and credit cards. The primary source of repayment for these loans is the income and assets of the borrower. The condition of the local economy, in particular the unemployment rate, is an important indicator of risk for this segment. The value of the collateral, if there is any, is less likely to be a source of repayment due to less certain collateral values. We further assess risk within each portfolio segment by pooling loans with similar risk characteristics. For the commercial loan classes, the most important indicator of risk is the internally assigned risk rating, including pass, special mention and substandard. Consumer loans are pooled by type of collateral, lien position and loan to value, or LTV, ratio for Consumer Real Estate loans. Historical loss rates are applied to these loan pools to determine the reserve for loans collectively evaluated for impairment. The ALL methodology for groups of loans collectively evaluated for impairment is comprised of both a quantitative and qualitative analysis. A key assumption in the quantitative component of the reserve is the loss emergence period, or LEP. The LEP is an estimate of the average amount of time from the point at which a loss is incurred on a loan to the point at which the loss is confirmed. Another key assumption is the look-back period, or LBP, which represents the historical data period utilized to calculate loss rates. Management monitors various credit quality indicators for both the commercial and consumer loan portfolios, including delinquency, nonperforming status and changes in risk ratings on a monthly basis.
Loan Credit Risk Rating	We continually monitor the commercial loan portfolio through an internal risk rating system. Loan risk ratings are assigned based upon the creditworthiness of the borrower and are reviewed on an ongoing basis according to our internal policies. Loans within the pass rating generally have a lower risk of loss than loans risk rated as special mention and substandard. Our risk ratings are consistent with regulatory guidance and are as follows: Pass —The loan is currently performing and is of high quality. Special Mention —A special mention loan has potential weaknesses that warrant management’s close attention. If left uncorrected, these potential weaknesses may result in deterioration of the repayment prospects or in the strength of our credit position at some future date. Economic and market conditions, beyond the borrower’s control, may in the future necessitate this classification. Substandard —A substandard loan is not adequately protected by the net worth and/or paying capacity of the borrower or by the collateral pledged, if any. Substandard loans have a well-defined weakness or weaknesses that jeopardize the liquidation of the debt. These loans are characterized by the distinct possibility that we will sustain some loss if the deficiencies are not corrected.

Summary of Significant Accoun36

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Estimated Useful Lives for Various Asset	The estimated useful lives for the various asset categories are as follows: 1) Land and Land Improvements Non-depreciating assets 2) Buildings 25 years 3) Furniture and Fixtures 5 years 4) Computer Equipment and Software 5 years or term of license 5) Other Equipment 5 years 6) Vehicles 5 years 7) Leasehold Improvements Lesser of estimated useful life of the asset (generally 15 years unless established otherwise) or the remaining term of the lease, including renewal options in the lease that are reasonably assured of exercise

Business Combinations (Tables)

Business Combinations (Tables)	12 Months Ended
	Dec. 31, 2016
Business Combinations [Abstract]
Summary of Consideration, Assets Acquired and Liabilities Assumed	The following table summarizes total consideration, assets acquired and liabilities assumed from the Merger: (dollars in thousands) Consideration Paid Cash $ 29,510 Common stock 142,469 Fair Value of Total Consideration $ 171,979 Fair Value of Assets Acquired Cash and cash equivalents $ 13,163 Securities and other investments 11,502 Loans 788,687 Bank owned life insurance 15,974 Premises and equipment 10,855 Core deposit intangible 5,713 Other assets 19,088 Total Assets Acquired 864,982 Fair Value of Liabilities Assumed Deposits 722,308 Borrowings 82,286 Other liabilities 4,259 Total Liabilities Assumed 808,853 Total Fair Value of Identifiable Net Assets 56,129 Goodwill $ 115,850

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2016
Earnings Per Share [Abstract]
Reconciles Numerators and Denominators of Basic Earnings Per Share and Diluted Earnings Per Share	The following table reconciles the numerators and denominators of basic and diluted EPS: Years ended December 31, (dollars in thousands, except share and per share data) 2016 2015 2014 Numerator for Earnings per Common Share—Basic: Net income $ 71,392 $ 67,081 $ 57,910 Less: Income allocated to participating shares 225 280 165 Net Income Allocated to Common Shareholders $ 71,167 $ 66,801 $ 57,745 Numerator for Earnings per Common Share—Diluted: Net income $ 71,392 $ 67,081 $ 57,910 Denominators: Weighted Average Common Shares Outstanding—Basic 34,677,738 33,812,990 29,683,103 Add: Dilutive potential common shares 95,432 35,092 25,621 Denominator for Treasury Stock Method—Diluted 34,773,170 33,848,082 29,708,724 Weighted Average Common Shares Outstanding—Basic 34,677,738 33,812,990 29,683,103 Add: Average participating shares outstanding 109,755 141,558 84,918 Denominator for Two-Class Method—Diluted 34,787,493 33,954,548 29,768,021 Earnings per common share—basic $ 2.06 $ 1.98 $ 1.95 Earnings per common share—diluted $ 2.05 $ 1.98 $ 1.95 Warrants considered anti-dilutive excluded from dilutive potential common shares - exercise price $31.53 per share, expires January 2019 517,012 517,012 517,012 Stock options considered anti-dilutive excluded from dilutive potential common shares — — 419,538 Restricted stock considered anti-dilutive excluded from dilutive potential common shares 116,749 106,466 59,297

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Assets and Liabilities Measured at Fair Value on Recurring Basis	The following tables present our assets and liabilities that are measured at fair value on a recurring basis by fair value hierarchy level at December 31, 2016 and 2015. December 31, 2016 (dollars in thousands) Level 1 Level 2 Level 3 Total ASSETS Securities available-for-sale: U.S. Treasury securities $ — $ 24,811 $ — $ 24,811 Obligations of U.S. government corporations and agencies — 232,179 — 232,179 Collateralized mortgage obligations of U.S. government corporations and agencies — 129,777 — 129,777 Residential mortgage-backed securities of U.S. government corporations and agencies — 37,358 — 37,358 Commercial mortgage-backed securities of U.S. government corporations and agencies — 125,604 — 125,604 Obligations of states and political subdivisions — 132,509 — 132,509 Marketable equity securities — 11,249 — 11,249 Total securities available-for-sale — 693,487 — 693,487 Trading securities held in a Rabbi Trust 4,410 — — 4,410 Total securities 4,410 693,487 — 697,897 Derivative financial assets: Interest rate swaps — 6,960 — 6,960 Interest rate lock commitments — 236 — 236 Total Assets $ 4,410 $ 700,683 $ — $ 705,093 LIABILITIES Derivative financial liabilities: Interest rate swaps $ — $ 6,958 $ — $ 6,958 Forward sale contracts — 27 — 27 Total Liabilities $ — $ 6,985 $ — $ 6,985 December 31, 2015 (dollars in thousands) Level 1 Level 2 Level 3 Total ASSETS Securities available-for-sale: U.S. Treasury securities $ — $ 14,941 $ — $ 14,941 Obligations of U.S. government corporations and agencies — 263,303 — 263,303 Collateralized mortgage obligations of U.S. government corporations and agencies — 128,835 — 128,835 Residential mortgage-backed securities of U.S. government corporations and agencies — 40,125 — 40,125 Commercial mortgage-backed securities of U.S. government corporations and agencies — 69,204 — 69,204 Obligations of states and political subdivisions — 134,886 — 134,886 Marketable equity securities — 9,669 — 9,669 Total securities available-for-sale 660,963 — 660,963 Trading securities held in a Rabbi Trust 4,021 — — 4,021 Total securities 4,021 660,963 — 664,984 Derivative financial assets: Interest rate swaps — 11,295 — 11,295 Interest rate lock commitments — 261 — 261 Total Assets $ 4,021 $ 672,519 $ — $ 676,540 LIABILITIES Derivative financial liabilities: Interest rate swaps $ — $ 11,276 $ — $ 11,276 Forward Sale Contracts — 5 — 5 Total Liabilities $ — $ 11,281 $ — $ 11,281
Assets Measured at Fair Value on Nonrecurring Basis by Fair Value Hierarchy	The following table presents our assets that are measured at fair value on a nonrecurring basis by the fair value hierarchy level as of the dates presented: December 31, 2016 December 31, 2015 (dollars in thousands) Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total ASSETS (1) Loans held for sale $ — $ — $ 1,802 $ 1,802 $ — $ — $ — $ — Impaired loans — — 10,329 10,329 — — 9,373 9,373 Other real estate owned — — 396 396 — — 158 158 Mortgage servicing rights — — 4,098 4,098 — — 3,396 3,396 Total Assets $ — $ — $ 16,625 $ 16,625 $ — $ — $ 12,927 $ 12,927 (1) This table presents only the nonrecurring items that are recorded at fair value in our financial statements.
Carrying Values and Fair Values of Financial Instruments	The carrying values and fair values of our financial instruments at December 31, 2016 and 2015 are presented in the following tables: Fair Value Measurements at December 31, 2016 (dollars in thousands) Carrying Value (1) Total Level 1 Level 2 Level 3 ASSETS Cash and due from banks, including interest-bearing deposits $ 139,486 $ 139,486 $ 139,486 $ — $ — Securities available-for-sale 693,487 693,487 — 693,487 — Loans held for sale 3,793 3,815 — — 3,815 Portfolio loans, net of unearned income 5,611,419 5,551,266 — — 5,551,266 Bank owned life insurance 72,081 72,081 — 72,081 — FHLB and other restricted stock 31,817 31,817 — — 31,817 Trading securities held in a Rabbi Trust 4,410 4,410 4,410 — — Mortgage servicing rights 3,744 4,098 — — 4,098 Interest rate swaps 6,960 6,960 — 6,960 — Interest rate lock commitments 236 236 — 236 — LIABILITIES Deposits $ 5,272,377 $ 5,276,499 $ — $ — $ 5,276,499 Securities sold under repurchase agreements 50,832 50,832 — — 50,832 Short-term borrowings 660,000 660,000 — — 660,000 Long-term borrowings 14,713 15,267 — — 15,267 Junior subordinated debt securities 45,619 45,619 — — 45,619 Interest rate swaps 6,958 6,958 — 6,958 — Forward sale contracts 27 27 — 27 — (1) As reported in the Consolidated Balance Sheets Fair Value Measurements at December 31, 2015 (dollars in thousands) Carrying Value (1) Total Level 1 Level 2 Level 3 ASSETS Cash and due from banks, including interest-bearing deposits $ 99,399 $ 99,399 $ 99,399 $ — $ — Securities available-for-sale 660,963 660,963 — 660,963 — Loans held for sale 35,321 35,500 — — 35,500 Portfolio loans, net of unearned income 5,027,612 5,001,004 — — 5,001,004 Bank owned life insurance 70,175 70,175 — 70,175 — FHLB and other restricted stock 23,032 23,032 — — 23,032 Trading securities held in a Rabbi Trust 4,021 4,021 4,021 — — Mortgage servicing rights 3,237 3,396 — — 3,396 Interest rate swaps 11,295 11,295 — 11,295 — Interest rate lock commitments 261 261 — 261 — LIABILITIES Deposits $ 4,876,611 $ 4,881,718 $ — $ — $ 4,881,718 Securities sold under repurchase agreements 62,086 62,086 — — 62,086 Short-term borrowings 356,000 356,000 — — 356,000 Long-term borrowings 117,043 117,859 — — 117,859 Junior subordinated debt securities 45,619 45,619 — — 45,619 Interest rate swaps 11,276 11,276 — 11,276 — Forward sale contracts 5 5 — 5 — (1) As reported in the Consolidated Balance Sheets

Securities Available-for-Sale (

Securities Available-for-Sale (Tables)	12 Months Ended
	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Composition of Securities Available-for-Sale	The following tables present the amortized cost and fair value of available-for-sale securities as of the dates presented: December 31, 2016 December 31, 2015 (dollars in thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S. Treasury securities $ 24,891 $ 47 $ (127 ) $ 24,811 $ 14,914 $ 27 $ — $ 14,941 Obligations of U.S. government corporations and agencies 230,989 1,573 (383 ) 232,179 262,045 1,825 (567 ) 263,303 Collateralized mortgage obligations of U.S. government corporations and agencies 130,046 465 (734 ) 129,777 128,458 693 (316 ) 128,835 Residential mortgage-backed securities of U.S. government corporations and agencies 36,606 984 (232 ) 37,358 39,185 1,091 (151 ) 40,125 Commercial mortgage-backed securities of U.S. government corporations and agencies 127,311 243 (1,950 ) 125,604 69,697 183 (676 ) 69,204 Obligations of states and political subdivisions 128,783 3,772 (46 ) 132,509 128,904 5,988 (6 ) 134,886 Debt Securities 678,626 7,084 (3,472 ) 682,238 643,203 9,807 (1,716 ) 651,294 Marketable equity securities 7,579 3,670 — 11,249 7,579 2,090 — 9,669 Total $ 686,205 $ 10,754 $ (3,472 ) $ 693,487 $ 650,782 $ 11,897 $ (1,716 ) $ 660,963
Schedule of Gross and Net Realized Gains and Losses on Sale of Securities	The following table shows the composition of gross and net realized gains and losses for the periods presented: Years ended December 31, (dollars in thousands) 2016 2015 2014 Gross realized gains $ — $ — $ 41 Gross realized losses — (34 ) — Net Realized (Losses) Gains $ — $ (34 ) $ 41
Fair Value and Age of Gross Unrealized Losses by Investment Category	The following tables present the fair value and the age of gross unrealized losses by investment category as of the dates presented: December 31, 2016 Less Than 12 Months 12 Months or More Total (dollars in thousands) Number of Securities Fair Unrealized Losses Number of Securities Fair Unrealized Losses Number of Securities Fair Unrealized Losses U.S. Treasury securities 1 $ 9,811 $ (127 ) — $ — $ — 1 $ 9,811 $ (127 ) Obligations of U.S. government corporations and agencies 7 62,483 (383 ) — — — 7 62,483 (383 ) Collateralized mortgage obligations of U.S. government corporations and agencies 10 83,031 (734 ) — — — 10 83,031 (734 ) Residential mortgage-backed securities of U.S. government corporations and agencies 2 10,022 (232 ) — — — 2 10,022 (232 ) Commercial mortgage-backed securities of U.S. government corporations and agencies 10 96,576 (1,950 ) — — — 10 96,576 (1,950 ) Obligations of states and political subdivisions 1 5,577 (46 ) — — — 1 5,577 (46 ) Debt Securities 31 267,500 (3,472 ) — — — 31 267,500 (3,472 ) Marketable equity securities — — — — — — — — — Total Temporarily Impaired Securities 31 $ 267,500 $ (3,472 ) — $ — $ — 31 $ 267,500 $ (3,472 ) December 31, 2015 Less Than 12 Months 12 Months or More Total (dollars in thousands) Number of Securities Fair Value Unrealized Losses Number of Securities Fair Value Unrealized Losses Number of Securities Fair Value Unrealized Losses U.S. Treasury securities — $ — $ — — $ — $ — — $ — $ — Obligations of U.S. government corporations and agencies 10 88,584 (379 ) 2 14,542 (188 ) 12 103,126 (567 ) Collateralized mortgage obligations of U.S. government corporations and agencies 6 61,211 (316 ) — — — 6 61,211 (316 ) Residential mortgage-backed securities of U.S. government corporations and agencies 1 7,993 (151 ) — — — 1 7,993 (151 ) Commercial mortgage-backed securities of U.S. government corporations and agencies 5 50,839 (450 ) 1 9,472 (226 ) 6 60,311 (676 ) Obligations of states and political subdivisions 1 5,370 (6 ) — — — 1 5,370 (6 ) Debt Securities 23 213,997 (1,302 ) 3 24,014 (414 ) 26 238,011 (1,716 ) Marketable equity securities — — — — — — — — — Total Temporarily Impaired Securities 23 $ 213,997 $ (1,302 ) 3 $ 24,014 $ (414 ) 26 $ 238,011 $ (1,716 )
Unrealized Gain (Loss) on Investments	The following table displays net unrealized gains and losses, net of tax, on securities available-for-sale included in accumulated other comprehensive income/(loss), for the periods presented: December 31, 2016 December 31, 2015 (dollars in thousands) Gross Unrealized Gains Gross Unrealized Losses Net Unrealized Gains (Losses) Gross Unrealized Gains Gross Unrealized Losses Net Unrealized Gains (Losses) Total unrealized gains (losses) on securities available for sale $ 10,754 $ (3,472 ) $ 7,282 $ 11,897 $ (1,716 ) $ 10,181 Income tax (expense) benefit (3,776 ) 1,219 (2,557 ) (4,164 ) 601 (3,563 ) Net unrealized gains (losses), net of tax included in accumulated other comprehensive income(loss) $ 6,978 $ (2,253 ) $ 4,725 $ 7,733 $ (1,115 ) $ 6,618
Amortized Cost and Fair Value of Available-for-Sale Securities	The amortized cost and fair value of securities available-for-sale at December 31, 2016 by contractual maturity are included in the table below. Actual maturities may differ from contractual maturities because issuers may have the right to call or prepay obligations with or without call or prepayment penalties. December 31, 2016 (dollars in thousands) Amortized Cost Fair Value Due in one year or less $ 52,594 $ 52,696 Due after one year through five years 201,450 203,513 Due after five years through ten years 64,569 64,975 Due after ten years 66,050 68,315 384,663 389,499 Collateralized mortgage obligations of U.S. government corporations and agencies 130,046 129,777 Residential mortgage-backed securities of U.S. government corporations and agencies 36,606 37,358 Commercial mortgage-backed securities of U.S. government corporations and agencies 127,311 125,604 Debt Securities 678,626 682,238 Marketable equity securities 7,579 11,249 Total $ 686,205 $ 693,487

Loans and Loans Held for Sale (

Loans and Loans Held for Sale (Tables)	12 Months Ended
	Dec. 31, 2016
Receivables [Abstract]
Composition of Loans	The following table indicates the composition of the acquired and originated loans as of the dates presented: December 31, (dollars in thousands) 2016 2015 Commercial Commercial real estate $ 2,498,476 $ 2,166,603 Commercial and industrial 1,401,035 1,256,830 Commercial construction 455,884 413,444 Total Commercial Loans 4,355,395 3,836,877 Consumer Residential mortgage 701,982 639,372 Home equity 482,284 470,845 Installment and other consumer 65,852 73,939 Consumer construction 5,906 6,579 Total Consumer Loans 1,256,024 1,190,735 Total Portfolio Loans 5,611,419 5,027,612 Loans held for sale 3,793 35,321 Total Loans $ 5,615,212 $ 5,062,933
Restructured Loans for Periods Presented	The following table summarizes the restructured loans as of the dates presented: December 31, 2016 December 31, 2015 (dollars in thousands) Performing TDRs Nonperforming TDRs Total TDRs Performing TDRs Nonperforming TDRs Total TDRs Commercial real estate $ 2,994 $ 646 $ 3,640 $ 6,822 $ 3,548 $ 10,370 Commercial and industrial 1,387 4,493 5,880 6,321 1,570 7,891 Commercial construction 2,966 430 3,396 5,013 1,265 6,278 Residential mortgage 2,375 5,068 7,443 2,590 665 3,255 Home equity 3,683 954 4,637 3,184 523 3,707 Installment and other consumer 18 7 25 25 88 113 Total $ 13,423 $ 11,598 $ 25,021 $ 23,955 $ 7,659 $ 31,614
Restructured Loans for Periods Stated	The following tables present the restructured loans for the 12 months ended December 31: 2016 (dollars in thousands) Number of Loans Pre-Modification Outstanding Recorded Investment (1) Post-Modification Outstanding Recorded Investment (1) Total Difference in Recorded Investment Commercial real estate Interest Rate Reduction 1 $ 250 $ 242 $ (8 ) Chapter 7 bankruptcy (2) 1 709 646 (63 ) Commercial and industrial Principal deferral 5 985 986 1 Maturity date extension 4 4,756 3,334 (1,422 ) Commercial construction Maturity date extension 3 1,251 1,151 (100 ) Residential mortgage Principal deferral 1 3,273 3,133 (140 ) Maturity date extension 1 483 414 (69 ) Maturity date extension and interest rate reduction 1 280 279 (1 ) Chapter 7 bankruptcy (2) 7 439 413 (26 ) Home equity Maturity date extension 5 305 298 (7 ) Maturity date extension and interest rate reduction 2 604 598 (6 ) Principal deferral 1 47 45 (2 ) Chapter 7 bankruptcy (2) 19 676 643 (33 ) Installment and other consumer Chapter 7 bankruptcy (2) 2 16 10 (6 ) Total by Concession Type Principal deferral 7 4,305 4,164 (141 ) Interest rate reduction 1 250 242 (8 ) Maturity date extension and interest rate reduction 3 884 877 (7 ) Maturity date extension 13 6,795 5,197 (1,598 ) Chapter 7 bankruptcy (2) 29 1,840 1,712 (128 ) Total 53 $ 14,074 $ 12,192 $ (1,882 ) (1) Excludes loans that were fully paid off or fully charged-off by period end. The pre-modification balance represents the balance outstanding prior to modification. The post-modification balance represents the outstanding balance at period end. (2) Chapter 7 bankruptcy loans where the debt has been legally discharged through the bankruptcy court and not reaffirmed. 2015 (dollars in thousands) Number of Loans Pre-Modification Outstanding Recorded Investment ( 1) Post-Modification Outstanding Recorded Investment (1 ) Total Difference in Recorded Investment Commercial real estate Principal deferral 2 $ 2,851 $ 1,841 $ (1,010 ) Maturity date extension 3 438 427 (11 ) Commercial and industrial Principal deferral 6 661 363 (298 ) Maturity date extension 2 824 728 (96 ) Commercial construction Maturity date extension 3 1,434 1,432 (2 ) Residential mortgage Maturity date extension 8 545 265 (280 ) Maturity date extension and interest rate reduction 1 207 205 (2 ) Chapter 7 bankruptcy (2) 7 428 226 (202 ) Home Equity Maturity date extension and interest rate reduction 3 203 201 (2 ) Maturity date extension 1 71 70 (1 ) Chapter 7 bankruptcy (2) 23 619 576 (43 ) Installment and other consumer Chapter 7 bankruptcy (2) 1 9 4 (5 ) Total by Concession Type Principal deferral 8 3,512 2,204 (1,308 ) Maturity date extension and interest rate reduction 4 410 406 (4 ) Maturity date extension 17 3,312 2,922 (390 ) Chapter 7 bankruptcy (2) 31 1,056 806 (250 ) Total 60 $ 8,290 $ 6,338 $ (1,952 ) (1) Excludes loans that were fully paid off or fully charged-off by period end. The pre-modification balance represents the balance outstanding prior to modification. The post-modification balance represents the outstanding balance at period end. (2) Chapter 7 bankruptcy loans where the debt has been legally discharged through the bankruptcy court and not reaffirmed.
Summary of Nonperforming Assets of Defaulted TDRs	defaulted during the years ended December 31, 2016 and 2015 that were restructured within the last 12 months prior to defaulting.
Summary of Nonperforming Assets	The following table is a summary of nonperforming assets as of the dates presented: December 31, (dollars in thousands) 2016 2015 Nonperforming Assets Nonaccrual loans $ 31,037 $ 27,723 Nonaccrual TDRs 11,598 7,659 Total nonaccrual loans 42,635 35,382 OREO 679 354 Total Nonperforming Assets $ 43,314 $ 35,736
Summary of Aggregate Amount of Loans	The following table presents a summary of the aggregate amount of loans to any such persons as of December 31: (dollars in thousands) 2016 2015 Balance at beginning of year $ 24,517 $ 27,368 New loans 22,740 24,743 Repayments (22,090 ) (27,594 ) Balance at End of Year $ 25,167 $ 24,517

Allowance for Loan Losses (Tabl

Allowance for Loan Losses (Tables)	12 Months Ended
	Dec. 31, 2016
Receivables [Abstract]
Age Analysis of Past Due Loans Segregated by Class of Loans	The following tables present the age analysis of past due loans segregated by class of loans as of the dates presented: December 31, 2016 (dollars in thousands) Current 30-59 Days Past Due 60-89 Days Past Due Non- performing Total Past Due Loans Total Loans Commercial real estate $ 2,479,513 $ 2,032 $ 759 $ 16,172 $ 18,963 $ 2,498,476 Commercial and industrial 1,391,475 1,061 428 8,071 9,560 1,401,035 Commercial construction 450,410 547 — 4,927 5,474 455,884 Residential mortgage 689,635 1,312 1,117 9,918 12,347 701,982 Home equity 476,866 1,470 509 3,439 5,418 482,284 Installment and other consumer 65,525 176 43 108 327 65,852 Consumer construction 5,906 — — — — 5,906 Loans held for sale 3,793 — — — — 3,793 Total $ 5,563,123 $ 6,598 $ 2,856 $ 42,635 $ 52,089 $ 5,615,212 December 31, 2015 (dollars in thousands) Current 30-59 Days Past Due 60-89 Days Past Due Non- performing Total Past Due Loans Total Loans Commercial real estate $ 2,145,655 $ 11,602 $ 627 $ 8,719 $ 20,948 $ 2,166,603 Commercial and industrial 1,244,802 2,453 296 9,279 12,028 1,256,830 Commercial construction 401,084 3,517 90 8,753 12,360 413,444 Residential mortgage 631,085 1,728 930 5,629 8,287 639,372 Home equity 465,055 2,365 523 2,902 5,790 470,845 Installment and other consumer 73,486 242 111 100 453 73,939 Consumer construction 6,579 — — — — 6,579 Loans held for sale 35,179 94 48 — 142 35,321 Total $ 5,002,925 $ 22,001 $ 2,625 $ 35,382 $ 60,008 $ 5,062,933
Recorded Investment in Commercial Loan Classes by Internally Assigned Risk Ratings	The following tables present the recorded investment in commercial loan classes by internally assigned risk ratings as of the dates presented: December 31, 2016 (dollars in thousands) Commercial Real Estate % of Total Commercial and Industrial % of Total Commercial Construction % of Total Total % of Total Pass $ 2,423,742 97.0 % $ 1,315,507 93.9 % $ 430,472 94.4 % $ 4,169,721 95.7 % Special mention 33,098 1.3 % 40,409 2.9 % 14,691 3.2 % 88,198 2.0 % Substandard 41,636 1.7 % 45,119 3.2 % 10,721 2.4 % 97,476 2.3 % Total $ 2,498,476 100.0 % $ 1,401,035 100.0 % $ 455,884 100.0 % $ 4,355,395 100.0 % December 31, 2015 (dollars in thousands) Commercial Real Estate % of Total Commercial and Industrial % of Total Commercial Construction % of Total Total % of Total Pass $ 2,094,851 96.7 % $ 1,182,685 94.1 % $ 375,808 90.9 % $ 3,653,344 95.2 % Special mention 19,938 0.9 % 43,896 3.5 % 19,846 4.8 % 83,680 2.2 % Substandard 51,814 2.4 % 30,249 2.4 % 17,790 4.3 % 99,853 2.6 % Total $ 2,166,603 100.0 % $ 1,256,830 100.0 % $ 413,444 100.0 % $ 3,836,877 100.0 %
Recorded Investment in Consumer Loan Classes by Performing and Nonperforming Status	The following tables present the recorded investment in consumer loan classes by performing and nonperforming status as of the dates presented: December 31, 2016 (dollars in thousands) Residential Mortgage % of Total Home Equity % of Total Installment and other consumer % of Total Consumer Construction % of Total Total % of Total Performing $ 692,064 98.6 % $ 478,845 99.3 % $ 65,744 99.8 % $ 5,906 100.0 % $ 1,242,559 98.9 % Nonperforming 9,918 1.4 % 3,439 0.7 % 108 0.2 % — — % 13,465 1.1 % Total $ 701,982 100.0 % $ 482,284 100.0 % $ 65,852 100.0 % $ 5,906 100.0 % $ 1,256,024 100.0 % December 31, 2015 (dollars in thousands) Residential Mortgage % of Total Home Equity % of Total Installment and other consumer % of Total Consumer Construction % of Total Total % of Total Performing $ 633,743 99.1 % $ 467,943 99.4 % $ 73,839 99.8 % $ 6,579 100.0 % $ 1,182,104 99.3 % Nonperforming 5,629 0.9 % 2,902 0.6 % 100 0.2 % — — % 8,631 0.7 % Total $ 639,372 100.0 % $ 470,845 100.0 % $ 73,939 100.0 % $ 6,579 100.0 % $ 1,190,735 100.0 %
Investments in Loans Considered to be Impaired and Related Information on Impaired Loans	The following tables summarize investments in loans considered to be impaired and related information on those impaired loans as of the dates presented: December 31, 2016 December 31, 2015 (dollars in thousands) Recorded Investment Unpaid Principal Balance Related Allowance Recorded Investment Unpaid Principal Balance Related Allowance With a related allowance recorded: Commercial real estate $ — $ — $ — $ — $ — $ — Commercial and industrial 964 2,433 771 — — — Commercial construction — — — 500 1,350 3 Consumer real estate 26 26 26 116 116 32 Other consumer 1 1 1 2 2 2 Total with a Related Allowance Recorded 991 2,460 798 618 1,468 37 Without a related allowance recorded: Commercial real estate 16,352 17,654 — 12,661 13,157 — Commercial and industrial 5,902 7,699 — 14,417 15,220 — Commercial construction 6,613 10,306 — 10,998 14,200 — Consumer real estate 12,053 12,849 — 6,845 7,521 — Other consumer 24 31 — 111 188 — Total without a Related Allowance Recorded 40,944 48,539 — 45,032 50,286 — Total: Commercial real estate 16,352 17,654 — 12,661 13,157 — Commercial and industrial 6,866 10,132 771 14,417 15,220 — Commercial construction 6,613 10,306 — 11,498 15,550 3 Consumer real estate 12,079 12,875 26 6,961 7,637 32 Other consumer 25 32 1 113 190 2 Total $ 41,935 $ 50,999 $ 798 $ 45,650 $ 51,754 $ 37 The following table summarizes investments in loans considered to be impaired and related information on those impaired loans for the years presented: For the Year Ended December 31, 2016 December 31, 2015 (dollars in thousands) Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized Without a related allowance recorded: Commercial real estate 17,496 144 14,622 597 Commercial and industrial 6,141 160 14,416 450 Commercial construction 7,723 162 10,581 329 Consumer real estate 11,939 523 6,902 364 Other consumer 35 1 117 1 Total without a Related Allowance Recorded 43,334 990 46,638 1,741 With a related allowance recorded: Commercial real estate — — — — Commercial and industrial 2,438 — — — Commercial construction — — 834 — Consumer real estate 28 2 120 7 Other consumer 2 — 2 — Total with a Related Allowance Recorded 2,468 2 956 7 Total: Commercial real estate 17,496 144 14,622 597 Commercial and industrial 8,579 160 14,416 450 Commercial construction 7,723 162 11,415 329 Consumer real estate 11,967 525 7,022 371 Other consumer 37 1 119 1 Total $ 45,802 $ 992 $ 47,594 $ 1,748
Summary of Allowance for Loan Losses	The following tables detail activity in the ALL for the periods presented: 2016 (dollars in thousands) Commercial Real Estate Commercial and Industrial Commercial Construction Consumer Real Estate Other Consumer Total Loans Balance at beginning of year $ 15,043 $ 10,853 $ 12,625 $ 8,400 $ 1,226 $ 48,147 Charge-offs (3,114 ) (6,810 ) (1,877 ) (1,657 ) (2,103 ) (15,561 ) Recoveries 692 722 21 433 356 2,224 Net (Charge-offs) Recoveries (2,422 ) (6,088 ) (1,856 ) (1,224 ) (1,747 ) (13,337 ) Provision for loan losses 7,355 6,045 3,230 (1,081 ) 2,416 17,965 Balance at End of Year $ 19,976 $ 10,810 $ 13,999 $ 6,095 $ 1,895 $ 52,775 2015 (dollars in thousands) Commercial Real Estate Commercial and Industrial Commercial Construction Consumer Real Estate Other Consumer Total Loans Balance at beginning of year $ 20,164 $ 13,668 $ 6,093 $ 6,333 $ 1,653 $ 47,911 Charge-offs (2,787 ) (5,463 ) (3,321 ) (2,167 ) (1,528 ) (15,266 ) Recoveries 3,545 605 143 495 326 5,114 Net Recoveries (Charge-offs) 758 (4,858 ) (3,178 ) (1,672 ) (1,202 ) (10,152 ) Provision for loan losses (5,879 ) 2,043 9,710 3,739 775 10,388 Balance at End of Year $ 15,043 $ 10,853 $ 12,625 $ 8,400 $ 1,226 $ 48,147
Summary of Allowance for Loan Losses and Recorded Investments	The following tables present the ALL and recorded investments in loans by category as of December 31: 2016 Allowance for Loan Losses Portfolio Loans (dollars in thousands) Individually Evaluated for Impairment Collectively Evaluated for Impairment Total Individually Evaluated for Impairment Collectively Evaluated for Impairment Total Commercial real estate $ — $ 19,976 $ 19,976 $ 16,352 $ 2,482,124 $ 2,498,476 Commercial and industrial 771 10,039 10,810 6,866 1,394,169 1,401,035 Commercial construction — 13,999 13,999 6,613 449,271 455,884 Consumer real estate 26 6,069 6,095 12,079 1,178,093 1,190,172 Other consumer 1 1,894 1,895 25 65,827 65,852 Total $ 798 $ 51,977 $ 52,775 $ 41,935 $ 5,569,484 $ 5,611,419 2015 Allowance for Loan Losses Portfolio Loans (dollars in thousands) Individually Evaluated for Impairment Collectively Evaluated for Impairment Total Individually Evaluated for Impairment Collectively Evaluated for Impairment Total Commercial real estate $ — $ 15,043 $ 15,043 $ 12,661 $ 2,153,942 $ 2,166,603 Commercial and industrial — 10,853 10,853 14,417 1,242,413 1,256,830 Commercial construction 3 12,622 12,625 11,498 401,946 413,444 Consumer real estate 32 8,368 8,400 6,961 1,109,835 1,116,796 Other consumer 2 1,224 1,226 113 73,826 73,939 Total $ 37 $ 48,110 $ 48,147 $ 45,650 $ 4,981,962 $ 5,027,612

Premises and Equipment (Tables)

Premises and Equipment (Tables)	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Summary of Premises and Equipment	The following table is a summary of premises and equipment as of the dates presented: December 31, (dollars in thousands) 2016 2015 Land $ 6,397 $ 8,699 Premises 52,696 52,968 Furniture and equipment 32,328 29,543 Leasehold improvements 7,293 7,186 98,714 98,396 Accumulated depreciation (53,715 ) (49,269 ) Total $ 44,999 $ 49,127
Minimum Annual Rental and Renewal Option Payments	Minimum annual rental and renewal option payments for each of the following five years and thereafter are approximately: (dollars in thousands) Operating Capital Total 2017 $ 3,388 $ 76 $ 3,464 2018 3,394 76 3,470 2019 3,430 76 3,506 2020 3,380 77 3,457 2021 3,401 77 3,478 Thereafter 57,864 534 58,398 Total $ 74,857 $ 916 $ 75,773

Goodwill and Other Intangible44

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	The following table presents goodwill as of the dates presented: December 31, (dollars in thousands) 2016 2015 Balance at beginning of year $ 291,764 $ 175,820 Additions — 115,944 Other adjustments (94 ) — Balance at End of Year $ 291,670 $ 291,764
Summary of Intangible Assets	The following table shows a summary of intangible assets as of the dates presented: December 31, (dollars in thousands) 2016 2015 Gross carrying amount at beginning of year $ 22,114 $ 16,401 Additions — 5,713 Accumulated amortization (17,204 ) (15,589 ) Balance at End of Year $ 4,910 $ 6,525
Summary of Expected Amortization Expense for Finite-Lived Intangibles Assets	The following is a summary of the expected amortization expense for finite-lived intangible assets, assuming no new additions, for each of the five years following December 31, 2016: (dollars in thousands) Amount 2017 $ 1,311 2018 812 2019 689 2020 588 2021 512 Total $ 3,912

Derivative Instruments and He45

Derivative Instruments and Hedging Activities (Tables)	12 Months Ended
	Dec. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Value of Derivative Assets and Derivative Liabilities	The following table indicates the amounts representing the value of derivative assets and derivative liabilities at December 31: Derivatives (included in Other Assets) Derivatives (included in Other Liabilities) (dollars in thousands) 2016 2015 2016 2015 Derivatives not Designated as Hedging Instruments Interest Rate Swap Contracts—Commercial Loans Fair value $ 6,960 $ 11,295 $ 6,958 $ 11,276 Notional amount 232,396 245,595 232,396 245,595 Collateral posted — — 14,340 12,753 Interest Rate Lock Commitments—Mortgage Loans Fair value 236 261 — — Notional amount 8,490 9,894 — — Forward Sale Contracts—Mortgage Loans Fair value — — 27 5 Notional amount — — 8,216 9,800
Schedule of Gross Amounts of Derivative Assets and Derivative Liabilities	The following table indicates the gross amounts of commercial loan swap derivative assets and derivative liabilities, the amounts offset and the carrying values in the Consolidated Balance Sheets at December 31: Derivatives (included in Other Assets) Derivatives (included in Other Liabilities) (dollars in thousands) 2016 2015 2016 2015 Derivatives not Designated as Hedging Instruments Gross amounts recognized $ 8,590 $ 11,295 $ 8,588 $ 11,276 Gross amounts offset (1,630 ) — (1,630 ) — Net amounts presented in the Consolidated Balance Sheets 6,960 11,295 6,958 11,276 Gross amounts not offset (1) — — (14,340 ) (12,573 ) Net Amount $ 6,960 $ 11,295 $ (7,382 ) $ (1,297 ) (1) Amounts represent posted collateral.
Amount of Gain or Loss Recognized in Income on Derivatives	The following table indicates the gain or loss recognized in income on derivatives for the years ended December 31: (dollars in thousands) 2016 2015 2014 Derivatives not Designated as Hedging Instruments Interest rate swap contracts—commercial loans $ (16 ) $ (8 ) $ (24 ) Interest rate lock commitments—mortgage loans (25 ) 26 150 Forward sale contracts—mortgage loans (22 ) 52 (90 ) Total Derivative(Loss) Gain $ (63 ) $ 70 $ 36

Mortgage Servicing Rights (Tabl

Mortgage Servicing Rights (Tables)	12 Months Ended
	Dec. 31, 2016
Transfers and Servicing of Financial Assets [Abstract]
Schedule of Mortgage Servicing Rights at Net Carrying Value	The following table indicates MSRs and the net carrying values: (dollars in thousands) Servicing Rights Valuation Allowance Net Carrying Value Balance at December 31, 2014 $ 3,108 $ (291 ) $ 2,817 Additions 856 — 856 Amortization (538 ) — (538 ) Temporary (impairment) recapture — 102 102 Balance at December 31, 2015 $ 3,426 $ (189 ) $ 3,237 Additions 1,047 — 1,047 Amortization (615 ) — (615 ) Temporary (impairment) recapture — 75 75 Balance at December 31, 2016 $ 3,858 $ (114 ) $ 3,744

Deposits (Tables)

Deposits (Tables)	12 Months Ended
	Dec. 31, 2016
Banking and Thrift [Abstract]
Composition of Deposits and Interest Expenses	The following table presents the composition of deposits at December 31 and interest expense for the years ended December 31: 2016 2015 2014 (dollars in thousands) Balance Interest Expense Balance Interest Expense Balance Interest Expense Noninterest-bearing demand $ 1,263,833 $ — $ 1,227,766 $ — $ 1,083,919 $ — Interest-bearing demand 638,300 111 616,188 818 335,099 19 Money market 936,461 4,199 605,184 1,299 376,612 572 Savings 1,050,131 2,002 1,061,265 1,712 1,027,095 1,607 Certificates of deposit 1,383,652 13,380 1,366,208 9,115 1,086,117 7,930 Total $ 5,272,377 $ 19,692 $ 4,876,611 $ 12,944 $ 3,908,842 $ 10,128
Scheduled Maturities of Certificates of Deposit	The following table indicates the scheduled maturities of certificates of deposit at December 31, 2016: (dollars in thousands) Amount 2017 $ 1,017,744 2018 221,829 2019 48,890 2020 38,629 2021 48,438 Thereafter 8,122 Total $ 1,383,652

Short-Term Borrowings (Tables)

Short-Term Borrowings (Tables)	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Composition of Short-Term Borrowings, Interest Expense and Weighted Average Interest Rate	The following table represents the composition of short-term borrowings, the weighted average interest rate as of December 31 and interest expense for the years ended December 31: 2016 2015 2014 (dollars in thousands) Balance Weighted Average Interest Rate Interest Expense Balance Weighted Average Interest Rate Interest Expense Balance Weighted Average Interest Rate Interest Expense REPOs $ 50,832 0.01 % $ 5 $ 62,086 0.01 % $ 4 $ 30,605 0.01 % $ 3 FHLB advances 660,000 0.76 % 2,713 356,000 0.52 % 932 290,000 0.31 % 511 Total Short-term Borrowings $ 710,832 0.70 % $ 2,718 $ 418,086 0.44 % $ 936 $ 320,605 0.27 % $ 514

Long-Term Borrowings and Subo49

Long-Term Borrowings and Subordinated Debt (Tables)	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Schedule of Long-Term Borrowings, Interest Expense and Weighted Average Interest Rate	The following table represents the balance of long-term borrowings, the weighted average interest rate as of December 31 and interest expense for the years ended December 31: (dollars in thousand) 2016 2015 2014 Long-term borrowings $ 14,713 $ 117,043 $ 19,442 Weighted average interest rate 2.91 % 0.81 % 3.00 % Interest expense $ 670 $ 790 $ 617
Schedule of Annual Maturities and Average Interest Rate of Long-Term Debt	Scheduled annual maturities and average interest rates for all of our long-term debt, including a capital lease of $0.1 million , for each of the five years and thereafter subsequent to December 31, 2016 are as follows: (dollars in thousands) Balance Average Rate 2017 $ 2,412 3.52 % 2018 2,496 3.60 % 2019 2,514 3.13 % 2020 2,004 3.22 % 2021 1,057 3.44 % Thereafter 4,230 1.84 % Total $ 14,713 2.94 %
Schedule of Junior Subordinated Debt Securities and Interest Expense	The following table represents the composition of junior subordinated debt securities at December 31 and the interest expense for the years ended December 31: 2016 2015 2014 (dollars in thousands) Balance Interest Expense Balance Interest Expense Balance Interest Expense 2006 Junior subordinated debt $ 25,000 $ 580 $ 25,000 $ 554 $ 25,000 $ 463 2008 Junior subordinated debt—trust preferred securities 20,619 854 20,619 773 20,619 759 Total $ 45,619 $ 1,434 $ 45,619 $ 1,327 $ 45,619 $ 1,222
Schedule of Junior Subordinated Debt Securities	The following table summarizes the key terms of our junior subordinated debt securities: (dollars in thousands) 2006 Junior Subordinated Debt 2008 Trust Preferred Securities Junior Subordinated Debt $25,000 — Trust Preferred Securities — $20,619 Stated Maturity Date 12/15/2036 3/15/2038 Optional redemption date at par Any time after 9/15/2011 Any time after 3/15/2013 Regulatory Capital Tier 2 Tier 1 Interest Rate 3 month LIBOR plus 160 bps 3 month LIBOR plus 350 bps Interest Rate at December 31, 2016 2.56% 4.46%

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Letters of Credit	The following table sets forth our commitments and letters of credit as of the dates presented: December 31, (dollars in thousands) 2016 2015 Commitments to extend credit $ 1,509,696 $ 1,619,854 Standby letters of credit 84,534 97,676 Total $ 1,594,230 $ 1,717,530
Future Estimated Payments Related to Data Processing and Communication Charges	The following table sets forth the future estimated payments related to data processing and communication charges for each of the five years following December 31, 2016: (dollars in thousands) Total 2017 $ 11,671 2018 12,046 2019 12,451 2020 12,875 2021 13,315 Total $ 62,358

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Schedule of Income Tax Expense (Benefit)	Income tax expense (benefit) for the years ended December 31 is comprised of: (dollars in thousands) 2016 2015 2014 Federal Current $ 24,521 $ 24,825 $ 15,979 Deferred 665 (427 ) 1,536 Total Federal 25,186 24,398 17,515 State Current 248 — — Deferred (129 ) — — Total State 119 — — Total Federal and State $ 25,305 $ 24,398 $ 17,515
Schedule of Statutory to Effective Tax Rate Reconciliation	The statutory to effective tax rate reconciliation for the years ended December 31 is as follows: 2016 2015 2014 Statutory tax rate 35.0 % 35.0 % 35.0 % Low income housing tax credits (3.8 )% (4.4 )% (5.8 )% Tax-exempt interest (4.4 )% (4.1 )% (4.6 )% Bank owned life insurance (0.8 )% (0.8 )% (0.8 )% Other 0.2 % 1.0 % (0.6 )% Effective Tax Rate 26.2 % 26.7 % 23.2 %
Schedule of Significant Components of Temporary Differences with Deferred Tax Assets and Liabilities	Significant components of our temporary differences were as follows at December 31: (dollars in thousands) 2016 2015 Deferred Tax Liabilities: Net unrealized holding gains on securities available-for-sale $ (2,557 ) $ (3,563 ) Prepaid pension (2,770 ) (2,865 ) Deferred loan income (3,815 ) (2,847 ) Depreciation on premises and equipment (1,239 ) (1,226 ) Other (1,766 ) (809 ) Total Deferred Tax liabilities (12,147 ) (11,310 ) Deferred Tax Assets: Allowance for loan losses 19,446 17,740 Purchase accounting adjustments 365 1,298 Other employee benefits 3,983 2,556 Low income housing partnerships 4,845 4,531 Net adjustment to funded status of pension 10,018 12,425 Impairment of securities 1,318 1,354 State net operating loss carryforwards 3,114 2,670 Other 4,984 6,155 Gross Deferred Tax Assets 48,073 48,729 Less: Valuation allowance (3,114 ) (2,670 ) Total Deferred Tax Assets 44,959 46,059 Net Deferred Tax Asset $ 32,812 $ 34,749
Schedule of Reconciliation of Change in Federal and State Gross Unrecognized Tax Benefits	The following table reconciles the change in Federal and State gross unrecognized tax benefits, or UTB, for the years ended December 31: (dollars in thousands) 2016 2015 2014 Balance at beginning of year $ 1,102 $ 284 $ 1,902 Prior period tax positions Increase — 818 55 Decrease (449 ) — (1,673 ) Current period tax positions 151 — — Reductions for statute of limitations expirations — — — Balance at End of Year $ 804 $ 1,102 $ 284 Amount That Would Impact the Effective Tax Rate if Recognized $ 610 $ 542 $ 184

Tax Effects on Other Comprehe52

Tax Effects on Other Comprehensive Income (Loss) (Tables)	12 Months Ended
	Dec. 31, 2016
Equity [Abstract]
Tax Effects of Components of Other Comprehensive Income (Loss)	The following tables present the tax effects of the components of other comprehensive income (loss) for the years ended December 31: (dollars in thousands) Pre-Tax Amount Tax (Expense) Benefit Net of Tax Amount 2016 Net change in unrealized gains on securities available-for-sale $ (2,899 ) $ 1,006 $ (1,893 ) Net available-for-sale securities losses (gains) reclassified into earnings — — — Adjustment to funded status of employee benefit plans 6,974 (2,408 ) 4,566 Other Comprehensive Income (Loss) $ 4,075 $ (1,402 ) $ 2,673 2015 Net change in unrealized gains on securities available-for-sale $ (663 ) $ 232 $ (431 ) Net available-for-sale securities losses reclassified into earnings 34 (12 ) 22 Adjustment to funded status of employee benefit plans (3,551 ) 1,336 (2,215 ) Other Comprehensive Income (Loss) $ (4,180 ) $ 1,556 $ (2,624 ) 2014 Net change in unrealized gains on securities available-for-sale $ 11,825 $ (4,139 ) $ 7,686 Net available-for-sale securities gains reclassified into earnings (41 ) 15 (26 ) Adjustment to funded status of employee benefit plans (13,394 ) 4,595 (8,799 ) Other Comprehensive Income (Loss) $ (1,610 ) $ 471 $ (1,139 )

Employee Benefits (Tables)

Employee Benefits (Tables)	12 Months Ended
	Dec. 31, 2016
Compensation and Retirement Disclosure [Abstract]
Benefit Obligation and Plan Assets Deriving Funded Status, in Other Liabilities	The following table summarizes the activity in the benefit obligation and Plan assets deriving the funded status, which is recorded in other liabilities in the Consolidated Balance Sheets: (dollars in thousands) 2016 2015 Change in Projected Benefit Obligation Projected benefit obligation at beginning of year $ 109,747 $ 113,124 Service cost 463 2,601 Interest cost 4,296 4,425 Actuarial loss (gain) 3,575 (4,257 ) Curtailments (6,997 ) — Benefits paid (5,250 ) (6,146 ) Projected Benefit Obligation at End of Year $ 105,834 $ 109,747 Change in Plan Assets Fair value of plan assets at beginning of year $ 84,585 $ 93,486 Actual return on plan assets 8,376 (2,755 ) Benefits paid (5,250 ) (6,146 ) Fair Value of Plan Assets at End of Year $ 87,711 $ 84,585 Funded Status $ (18,123 ) $ (25,162 )
Accumulated Other Comprehensive Income (Loss)	The following table sets forth the amounts recognized in accumulated other comprehensive income (loss) at December 31: (dollars in thousands) 2016 2015 Prior service credit $ — $ (1,029 ) Net actuarial loss 26,013 34,376 Total (Before Tax Effects) $ 26,013 $ 33,347
Actuarial Weighted Average Assumptions Used in Determining Benefit Obligation	Below are the actuarial weighted average assumptions used in determining the benefit obligation: 2016 2015 Discount rate 4.00 % 4.25 % Rate of compensation increase (1) — % 3.00 % (1) Rate of compensation increase is not applicable for 2016 due to the amendment to freeze benefit accruals under the qualified and nonqualified defined benefit pension plans effective March 31, 2016
Components of Net Periodic Pension Cost and Other Changes in Plan Assets and Benefit Obligation Recognized in Other Comprehensive Income (Loss)	The following table summarizes the components of net periodic pension cost and other changes in Plan assets and benefit obligations recognized in other comprehensive income (loss) for the years ended December 31: (dollars in thousands) 2016 2015 2014 Components of Net Periodic Pension Cost Service cost—benefits earned during the period $ 463 $ 2,601 $ 2,369 Interest cost on projected benefit obligation 4,296 4,425 4,470 Expected return on plan assets (5,780 ) (7,180 ) (6,907 ) Amortization of prior service credit (11 ) (138 ) (137 ) Recognized net actuarial loss 2,345 2,028 941 Curtailment (gain) (1,017 ) — — Net Periodic Pension Expense $ 296 $ 1,736 $ 736 Other Changes in Plan Assets and Benefit Obligation Recognized in Other Comprehensive Income (Loss) Net actuarial (gain) loss $ (6,018 ) $ 5,678 $ 13,294 Recognized net actuarial loss (2,345 ) (2,028 ) (941 ) Recognized prior service credit 1,029 138 137 Total (Before Tax Effects) $ (7,334 ) $ 3,788 $ 12,490 Total Recognized in Net Benefit Cost and Other Comprehensive (Loss)/Income (Before Tax Effects) $ (7,038 ) $ 5,524 $ 13,226
Actuarial Weighted Average Assumptions Used in Determining Net Periodic Pension Cost	The following table summarizes the actuarial weighted average assumptions used in determining net periodic pension cost: 2016 2015 2014 Discount rate 4.25 % 4.00 % 4.75 % Rate of compensation increase 3.00 % 3.00 % 3.00 % Expected return on assets 7.50 % 8.00 % 8.00 %
Estimated Future Benefit Payments	The following table provides information regarding estimated future benefit payments to be paid in each of the next five years and in the aggregate for the five years thereafter: (dollars in thousands) Amount 2017 $ 6,788 2018 6,855 2019 6,833 2020 6,748 2021 6,847 2022 - 2026 32,361
Pension Plan Assets Measured at Fair Value on Recurring Basis	The following tables present our Plan assets measured at fair value on a recurring basis by fair value hierarchy level at December 31, 2016 and 2015. There were no transfers between Level 1 and Level 2 for items of a recurring basis during the periods presented. There were no purchases or transfers of Level 3 plan assets in 2016. December 31, 2016 Fair Value Asset Classes (1) (dollars in thousands) Level 1 Level 2 Level 3 Total Cash and cash equivalents (2) $ — $ 3,336 $ — $ 3,336 Fixed income (3) 27,279 — — 27,279 Equities: Equity index mutual funds—international (4) 3,362 — — 3,362 Domestic individual equities (5) 53,636 — — 53,636 Total Assets at Fair Value $ 84,277 $ 3,336 $ — $ 87,613 (1) Refer to Note 1 Summary of Significant Accounting Policies, Fair Value Measurements for a description of levels within the fair value hierarchy. (2) This asset class includes FDIC insured money market instruments. (3) This asset class includes a variety of fixed income mutual funds which primarily invest in investment grade rated securities. Investment managers have discretion to invest in fixed income related securities including futures, options and other derivatives. Investments may be made in currencies other than the U.S. dollar. (4) The sole investment within this asset class is the Harbor International Institutional Fund. (5) This asset class includes individual domestic equities invested in an active all-cap strategy. It may also include convertible bonds. December 31, 2015 Fair Value Asset Classes (1) (dollars in thousands) Level 1 Level 2 Level 3 Total Cash and cash equivalents (2) $ — $ 3,371 $ — $ 3,371 Fixed income (3) 27,054 — — 27,054 Equities: Equity index mutual funds—international (4) 3,421 — — 3,421 Domestic individual equities (5) 50,739 — — 50,739 Total Assets at Fair Value $ 81,214 $ 3,371 $ — $ 84,585 (1) Refer to Note 1 Summary of Significant Accounting Policies, Fair Value Measurements for a description of levels within the fair value hierarchy. (2) This asset class includes FDIC insured money market instruments. (3) This asset class includes a variety of fixed income mutual funds which primarily invest in investment grade rated securities. Investment managers have discretion to invest in fixed income related securities including futures, options and other derivatives. Investments may be made in currencies other than the U.S. dollar. (4) The sole investment within this asset class is MSCI EAFE Index iShares. (5) This asset class includes individual domestic equities invested in an active all-cap strategy. It may also include convertible bonds.

Incentive and Restricted Stoc54

Incentive and Restricted Stock Plan and Dividend Reinvestment Plan (Tables)	12 Months Ended
	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of Nonstatutory Stock Options Activity	The following table summarizes activity for nonstatutory stock options for the years ended December 31: 2016 2015 2014 Number of Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Term Number of Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Term Number of Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Term Outstanding at beginning of year — $ — 155,500 $ 37.86 428,900 $ 37.36 Granted — — — — — — Exercised — — — — — — Forfeited — — — — (273,400 ) 37.08 Expired — — (155,500 ) 37.86 — — Outstanding at End of Year — $ — 0.0 years — $ — 0.0 years 155,500 $ 37.86 1.0 year Exercisable at End of Year — $ — 0.0 years — $ — 0.0 years 155,500 $ 37.86 1.0 year
Summary of Non-Vested Restricted Stock	The following table provides information about restricted stock granted under the 2014 Stock Plan for the years ended December 31: Restricted Stock Weighted Average Grant Date Fair Value Non-vested at December 31, 2014 79,824 $ 23.24 Granted 87,841 28.71 Vested 14,126 23.57 Forfeited 3,183 26.15 Non-vested at December 31, 2015 150,356 $ 26.34 Granted 110,643 25.58 Vested 32,164 25.03 Forfeited 3,335 26.04 Non-vested at December 31, 2016 225,500 $ 26.16

Parent Company Condensed Fina55

Parent Company Condensed Financial Information (Tables)	12 Months Ended
	Dec. 31, 2016
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Balance Sheets	BALANCE SHEETS December 31, (dollars in thousands) 2016 2015 ASSETS Cash $ 17,057 $ 12,595 Investments in: Bank subsidiary 819,531 777,795 Nonbank subsidiaries 21,980 20,624 Other assets 4,694 2,530 Total Assets $ 863,262 $ 813,544 LIABILITIES Long-term debt $ 20,619 $ 20,619 Other liabilities 687 688 Total Liabilities 21,306 21,307 Total Shareholders’ Equity 841,956 792,237 Total Liabilities and Shareholders’ Equity $ 863,262 $ 813,544
Statements of Net Income	STATEMENTS OF NET INCOME Years ended December 31, (dollars in thousands) 2016 2015 2014 Dividends from subsidiaries $ 34,134 $ 75,413 $ 46,414 Investment income 17 19 19 Interest expense on long-term debt 854 773 759 Other expenses 2,315 2,138 2,014 Income before Equity in Undistributed Net Income of Subsidiaries 30,982 72,521 43,660 Equity in undistributed net income (distribution in excess of net income) of: Bank subsidiary 40,051 (5,064 ) 13,351 Nonbank subsidiaries 359 (376 ) 899 Net Income $ 71,392 $ 67,081 $ 57,910
Statements of Cash Flows	STATEMENTS OF CASH FLOWS Years ended December 31, (dollars in thousands) 2016 2015 2014 OPERATING ACTIVITIES Net Income $ 71,392 $ 67,081 $ 57,910 Equity in undistributed (earnings) losses of subsidiaries (40,410 ) 5,440 (14,250 ) Tax benefit from stock-based compensation (9 ) (53 ) (16 ) Other 379 3,059 (106 ) Net Cash Provided by Operating Activities 31,352 75,527 43,538 INVESTING ACTIVITIES Net investments in subsidiaries — (38,404 ) — Acquisitions — (29,510 ) — Net Cash Used in Investing Activities — (67,914 ) — FINANCING ACTIVITIES Repayment of junior subordinated debt — (8,500 ) — (Purchase) Sale of treasury shares, net (115 ) (112 ) (163 ) Cash dividends paid to common shareholders (26,784 ) (24,487 ) (20,215 ) Tax benefit from stock-based compensation 9 53 16 Net Cash Used in Financing Activities (26,890 ) (33,046 ) (20,362 ) Net increase (decrease) in cash 4,462 (25,433 ) 23,176 Cash at beginning of year 12,595 38,028 14,852 Cash at End of Year $ 17,057 $ 12,595 $ 38,028

Regulatory Matters (Tables)

Regulatory Matters (Tables)	12 Months Ended
	Dec. 31, 2016
Banking and Thrift [Abstract]
Summary of Risk-Based Capital Amounts and Ratios	The following table summarizes risk-based capital amounts and ratios for S&T and S&T Bank: Actual Minimum Regulatory Capital Requirements To be Well Capitalized Under Prompt Corrective Action Provisions (dollars in thousands) Amount Ratio Amount Ratio Amount Ratio As of December 31, 2016 Leverage Ratio S&T $ 582,155 8.98 % $ 259,170 4.00 % $ 323,963 5.00 % S&T Bank 542,048 8.39 % 258,460 4.00 % 323,075 5.00 % Common Equity Tier 1 (to Risk-Weighted Assets) S&T 562,155 10.04 % 252,079 4.50 % 364,114 6.50 % S&T Bank 542,048 9.71 % 251,213 4.50 % 362,864 6.50 % Tier 1 Capital (to Risk-Weighted Assets) S&T 582,155 10.39 % 336,105 6.00 % 448,140 8.00 % S&T Bank 542,048 9.71 % 334,951 6.00 % 446,601 8.00 % Total Capital (to Risk-Weighted Assets) S&T 664,184 11.86 % 448,140 8.00 % 560,175 10.00 % S&T Bank 622,469 11.15 % 446,602 8.00 % 558,252 10.00 % As of December 31, 2015 Leverage Ratio S&T $ 535,234 8.96 % $ 238,841 4.00 % $ 298,551 5.00 % S&T Bank 502,114 8.43 % 238,121 4.00 % 297,651 5.00 % Common Equity Tier 1 (to Risk-Weighted Assets) S&T 515,234 9.77 % 237,315 4.50 % 342,788 6.50 % S&T Bank 502,114 9.55 % 236,482 4.50 % 341,584 6.50 % Tier 1 Capital (to Risk-Weighted Assets) S&T 535,234 10.15 % 316,419 6.00 % 421,892 8.00 % S&T Bank 502,114 9.55 % 315,309 6.00 % 420,412 8.00 % Total Capital (to Risk-Weighted Assets) S&T 611,859 11.60 % 421,892 8.00 % 527,366 10.00 % S&T Bank 577,824 11.00 % 420,412 8.00 % 525,515 10.00 %

Segments (Tables)

Segments (Tables)	12 Months Ended
	Dec. 31, 2016
Segment Reporting [Abstract]
Total Assets by Reportable Operating Segment	The following represents total assets by reportable operating segment as of December 31: (dollars in thousands) 2016 2015 Community Banking $ 6,930,712 $ 6,305,046 Insurance 9,226 9,619 Wealth Management 3,115 3,689 Total Assets $ 6,943,053 $ 6,318,354
Financial Information of Segments	For the Year Ended December 31, 2016 (dollars in thousands) Community Banking Insurance Wealth Management Eliminations Consolidated Interest income $ 227,756 $ 2 $ 459 $ (443 ) $ 227,774 Interest expense 24,851 — — (336 ) 24,515 Net interest income 202,905 2 459 (107 ) 203,259 Provision for loan losses 17,965 — — — 17,965 Noninterest income 37,717 4,794 10,443 1,681 54,635 Noninterest expense 120,744 4,582 9,751 1,574 136,651 Depreciation expense 4,905 45 16 — 4,966 Amortization of intangible assets 1,543 50 22 — 1,615 Provision for income taxes 24,872 42 391 — 25,305 Net Income $ 70,593 $ 77 $ 722 $ — $ 71,392 For the Year Ended December 31, 2015 (dollars in thousands) Community Banking Insurance Wealth Management Eliminations Consolidated Interest income $ 203,439 $ 2 $ 508 $ (401 ) $ 203,548 Interest expense 16,678 — — (681 ) 15,997 Net interest income 186,761 2 508 280 187,551 Provision for loan losses 10,388 — — — 10,388 Noninterest income 34,106 5,035 11,412 480 51,033 Noninterest expense 115,998 4,365 9,037 760 130,160 Depreciation expense 4,664 50 25 — 4,739 Amortization of intangible assets 1,738 50 30 — 1,818 Provision for income taxes 23,209 200 989 — 24,398 Net Income $ 64,870 $ 372 $ 1,839 $ — $ 67,081 For the Year Ended December 31, 2014 (dollars in thousands) Community Banking Insurance Wealth Management Eliminations Consolidated Interest income $ 160,403 $ 2 $ 518 $ (400 ) $ 160,523 Interest expense 13,989 — — (1,508 ) 12,481 Net interest income 146,414 2 518 1,108 148,042 Provision for loan losses 1,715 — — — 1,715 Noninterest income 29,443 5,279 11,297 319 46,338 Noninterest expense 97,733 4,313 9,173 1,427 112,646 Depreciation expense 3,387 51 27 — 3,465 Amortization of intangible assets 1,039 51 39 — 1,129 Provision (benefit) for income taxes 16,311 303 901 — 17,515 Net Income $ 55,672 $ 563 $ 1,675 $ — $ 57,910

Selected Financial Data (Tables

Selected Financial Data (Tables)	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Summary of Selected Financial Data	The following table presents selected financial data for the most recent eight quarters. 2016 2015 (dollars in thousands, except per share data) (unaudited) Fourth Quarter Third Quarter Second Quarter First Quarter Fourth Quarter Third Quarter Second Quarter First Quarter SUMMARY OF OPERATIONS Interest income $ 59,096 $ 57,808 $ 55,850 $ 55,019 $ 53,353 $ 53,669 $ 52,611 $ 43,916 Interest expense 6,638 6,353 6,142 5,382 4,468 4,073 3,800 3,657 Provision for loan losses 5,586 2,516 4,848 5,014 3,915 3,206 2,059 1,207 Net Interest Income After Provision For Loan Losses 46,872 48,939 44,860 44,623 44,970 46,390 46,752 39,052 Security (losses) gains, net — — — — — — (34 ) — Noninterest income 12,922 13,448 12,448 15,817 13,084 12,481 13,417 12,084 Noninterest expense 35,625 34,439 34,753 38,416 33,817 33,829 35,449 33,621 Income Before Taxes 24,169 27,948 22,555 22,024 24,237 25,042 24,686 17,515 Provision for income taxes 6,510 7,367 5,496 5,931 6,814 6,407 6,498 4,680 Net Income Available to Common Shareholders $ 17,659 $ 20,581 $ 17,059 $ 16,093 $ 17,423 $ 18,635 $ 18,188 $ 12,835 Per Share Data Common earnings per share—diluted $ 0.51 $ 0.59 $ 0.49 $ 0.46 $ 0.50 $ 0.54 $ 0.52 $ 0.41 Dividends declared per common share 0.20 0.19 0.19 0.19 0.19 0.18 0.18 0.18 Common book value 24.12 24.02 23.63 23.23 22.76 22.63 22.15 21.91

Summary of Significant Accoun59

Summary of Significant Accounting Policies - Additional Information (Details)	12 Months Ended
	Dec. 31, 2016USD ($)segmententitysubsidiary	Mar. 04, 2016USD ($)	Dec. 31, 2015USD ($)	Mar. 04, 2015USD ($)
Summary of Significant Accounting Policies [Line Items]
Number of subsidiary | subsidiary	3
Percentage of outstanding common stock of investees accounted for using equity method of accounting	100.00%
Prior period reclassification adjustment	$ 0
Number of entities non-banking activities | entity	5
Period for satisfactory payment of TDRs	6 months
Evaluation for impairment of substandard and nonaccrual commercial loans	$ 500,000
Number of reporting units | segment	3
Goodwill	$ 291,670,000		$ 291,764,000
Amortization period of intangible assets	10 years
Percentage of amount recognized of tax benefit	50.00%
Community Banking
Summary of Significant Accounting Policies [Line Items]
Goodwill	$ 287,400,000
Percentage of goodwill to reporting units	99.00%
Insurance
Summary of Significant Accounting Policies [Line Items]
Goodwill	$ 4,200,000
Percentage of goodwill to reporting units	1.00%
Interest Rate Lock Commitments
Summary of Significant Accounting Policies [Line Items]
Period for interest rate lock commitment	60 days
Integrity Bancshares, Inc.
Summary of Significant Accounting Policies [Line Items]
Goodwill		$ 115,850,000		$ 115,900,000
Common Wealth Trust Life Insurance Company
Summary of Significant Accounting Policies [Line Items]
Percentage of outstanding common stock of investees accounted for using equity method of accounting	50.00%
Minimum
Summary of Significant Accounting Policies [Line Items]
Percentage of outstanding common stock of investees accounted for using equity method of accounting	20.00%
Maximum
Summary of Significant Accounting Policies [Line Items]
Percentage of outstanding common stock of investees accounted for using equity method of accounting	50.00%
Core Deposits And Customers Lists | Minimum
Summary of Significant Accounting Policies [Line Items]
Acquired finite-lived intangibles, weighted average life	10 years
Core Deposits And Customers Lists | Maximum
Summary of Significant Accounting Policies [Line Items]
Acquired finite-lived intangibles, weighted average life	20 years
Corporate Joint Venture [Member]
Summary of Significant Accounting Policies [Line Items]
Percentage of outstanding common stock of investees accounted for using equity method of accounting	50.00%

Summary of Significant Accoun60

Summary of Significant Accounting Policies - Estimated Useful Lives for Various Asset (Details)	12 Months Ended
	Dec. 31, 2016
Land and Land Improvements
Property, Plant and Equipment [Line Items]
Estimated useful lives, description	Non-depreciating assets
Buildings
Property, Plant and Equipment [Line Items]
Estimated useful lives, years	25 years
Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Estimated useful lives, years	5 years
Computer Equipment and Software
Property, Plant and Equipment [Line Items]
Estimated useful lives, years	5 years
Other Equipment
Property, Plant and Equipment [Line Items]
Estimated useful lives, years	5 years
Vehicles
Property, Plant and Equipment [Line Items]
Estimated useful lives, years	5 years
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Estimated useful lives, years	15 years

Business Combinations Additiona

Business Combinations Additional Information (Details) - USD ($)	Mar. 04, 2015	Dec. 31, 2015	Dec. 31, 2016	Mar. 04, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill, adjustments during measurement period			$ (94,000)		$ 0
Goodwill		$ 291,764,000	291,670,000		291,764,000
Merger related expenses			0		3,167,000	$ 689,000
Data processing, contract termination and conversion cost expenses			0		1,300,000	0
Professional services and legal			4,212,000		3,365,000	$ 3,717,000
Integrity Bancshares, Inc.
Business Acquisition [Line Items]
Percentage of voting interests acquired	100.00%
Cash per share offered in exchange	$ 52.50
Shares of S&T offered for each share of Integrity (in shares)	2.0627
Fair value of consideration	$ 172,000,000			$ 171,979,000
Cash	$ 29,500,000			29,510,000
S&T common shares issued (in shares)	4,933,115
S&T common shares issued, fair value (in dollars per share)	$ 28.88
Goodwill, adjustments during measurement period		1,100,000	(100,000)
Purchase accounting adjustment, decrease to land		800,000
Purchase accounting adjustment, Decrease to deferred tax assets		$ 300,000
Goodwill	$ 115,900,000			115,850,000
Carryover of allowance for loan losses	0
Acquired loans	788,700,000			$ 788,687,000
Discount on Loans Acquired	14,800,000
Merger related expenses			$ 0		3,200,000
Data processing, contract termination and conversion cost expenses					1,300,000
Professional services and legal					1,200,000
Severance payments					400,000
Other expenses					$ 300,000
Integrity Bancshares, Inc. | Commercial Real Estate
Business Acquisition [Line Items]
Acquired loans	331,600,000
Integrity Bancshares, Inc. | Commercial and Industrial
Business Acquisition [Line Items]
Acquired loans	184,200,000
Integrity Bancshares, Inc. | Commercial Construction
Business Acquisition [Line Items]
Acquired loans	92,400,000
Integrity Bancshares, Inc. | Residential Mortgage
Business Acquisition [Line Items]
Acquired loans	116,900,000
Integrity Bancshares, Inc. | Home Equity
Business Acquisition [Line Items]
Acquired loans	25,600,000
Integrity Bancshares, Inc. | Installment and Other Consumer
Business Acquisition [Line Items]
Acquired loans	36,100,000
Integrity Bancshares, Inc. | Consumer Construction
Business Acquisition [Line Items]
Acquired loans	$ 1,900,000

Business Combinations Considera

Business Combinations Consideration, Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Mar. 04, 2015	Mar. 04, 2016	Dec. 31, 2016	Dec. 31, 2015
Fair Value of Liabilities Assumed
Goodwill			$ 291,670	$ 291,764
Integrity Bancshares, Inc.
Business Acquisition [Line Items]
Cash	$ 29,500	$ 29,510
Common stock		142,469
Fair Value of Total Consideration	172,000	171,979
Fair Value of Assets Acquired
Cash and cash equivalents		13,163
Securities and other investments		11,502
Loans	788,700	788,687
Bank owned life insurance		15,974
Premises and equipment		10,855
Core deposit intangible		5,713
Other assets		19,088
Total Assets Acquired		864,982
Fair Value of Liabilities Assumed
Deposits		722,308
Borrowings		82,286
Other liabilities		4,259
Total Liabilities Assumed		808,853
Total Fair Value of Identifiable Net Assets		56,129
Goodwill	$ 115,900	$ 115,850

Earnings Per Share - Reconcilia

Earnings Per Share - Reconciliation of Numerators and Denominators of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Numerator for Earnings per Common Share-Basic:
Net Income									$ 71,392	$ 67,081	$ 57,910
Less: Income allocated to participating shares									225	280	165
Net Income Available to Common Shareholders	$ 17,659	$ 20,581	$ 17,059	$ 16,093	$ 17,423	$ 18,635	$ 18,188	$ 12,835	71,167	66,801	57,745
Numerator for Earnings per Common Share-Diluted:
Net Income									$ 71,392	$ 67,081	$ 57,910
Denominators:
Weighted Average Common Shares Outstanding-Basic (in shares)									34,677,738	33,812,990	29,683,103
Add: Dilutive potential common shares (in shares)									95,432	35,092	25,621
Denominator for Treasury Stock Method-Diluted (in shares)									34,773,170	33,848,082	29,708,724
Weighted Average Common Shares Outstanding-Basic (in shares)									34,677,738	33,812,990	29,683,103
Add: Average participating shares outstanding (in shares)									109,755	141,558	84,918
Denominator for Two-Class Method-Diluted (in shares)									34,787,493	33,954,548	29,768,021
Earnings per common share—basic (in USD per share)									$ 2.06	$ 1.98	$ 1.95
Earnings per common share—diluted (in USD per share)	$ 0.51	$ 0.59	$ 0.49	$ 0.46	$ 0.50	$ 0.54	$ 0.52	$ 0.41	2.05	1.98	1.95
Exercise price of warrants (in USD per share)	$ 31.53				$ 31,530				$ 31.53	$ 31,530	$ 31,530
Warrants
Denominators:
Anti-dilutive excluded from dilutive potential common shares (in shares)									517,012	517,012	517,012
Stock Options
Denominators:
Anti-dilutive excluded from dilutive potential common shares (in shares)									0	0	419,538
Restricted Stock
Denominators:
Anti-dilutive excluded from dilutive potential common shares (in shares)									116,749	106,466	59,297

Fair Value Measurements - Asset

Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
ASSETS
Securities available-for-sale, at fair value	$ 693,487	$ 660,963
U.S. Treasury securities
ASSETS
Securities available-for-sale, at fair value	24,811	14,941
Obligations of U.S. government corporations and agencies
ASSETS
Securities available-for-sale, at fair value	232,179	263,303
Collateralized mortgage obligations of U.S. government corporations and agencies
ASSETS
Securities available-for-sale, at fair value	129,777	128,835
Residential mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Securities available-for-sale, at fair value	37,358	40,125
Commercial mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Securities available-for-sale, at fair value	125,604	69,204
Obligations of states and political subdivisions
ASSETS
Securities available-for-sale, at fair value	132,509	134,886
Marketable equity securities
ASSETS
Securities available-for-sale, at fair value	11,249	9,669
Fair Value Measurements, Recurring
ASSETS
Securities available-for-sale, at fair value	693,487	660,963
Trading securities held in a Rabbi Trust	4,410	4,021
Total securities	697,897	664,984
Total Assets	705,093	676,540
LIABILITIES
Total Liabilities	6,985	11,281
Fair Value Measurements, Recurring | U.S. Treasury securities
ASSETS
Securities available-for-sale, at fair value	24,811	14,941
Fair Value Measurements, Recurring | Obligations of U.S. government corporations and agencies
ASSETS
Securities available-for-sale, at fair value	232,179	263,303
Fair Value Measurements, Recurring | Collateralized mortgage obligations of U.S. government corporations and agencies
ASSETS
Securities available-for-sale, at fair value	129,777	128,835
Fair Value Measurements, Recurring | Residential mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Securities available-for-sale, at fair value	37,358	40,125
Fair Value Measurements, Recurring | Commercial mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Securities available-for-sale, at fair value	125,604	69,204
Fair Value Measurements, Recurring | Obligations of states and political subdivisions
ASSETS
Securities available-for-sale, at fair value	132,509	134,886
Fair Value Measurements, Recurring | Marketable equity securities
ASSETS
Securities available-for-sale, at fair value	11,249	9,669
Fair Value Measurements, Recurring | Interest Rate Swap
ASSETS
Derivative financial assets	6,960	11,295
LIABILITIES
Derivative financial liabilities	6,958	11,276
Fair Value Measurements, Recurring | Interest Rate Lock Commitments
ASSETS
Derivative financial assets	236	261
Fair Value Measurements, Recurring | Forward Sale Contracts
LIABILITIES
Derivative financial liabilities	27	5
Fair Value Measurements, Recurring | Level 1
ASSETS
Securities available-for-sale, at fair value
Trading securities held in a Rabbi Trust	4,410	4,021
Total securities	4,410	4,021
Total Assets	4,410	4,021
Fair Value Measurements, Recurring | Level 1 | U.S. Treasury securities
ASSETS
Securities available-for-sale, at fair value	0	0
Fair Value Measurements, Recurring | Level 1 | Obligations of U.S. government corporations and agencies
ASSETS
Securities available-for-sale, at fair value	0	0
Fair Value Measurements, Recurring | Level 1 | Collateralized mortgage obligations of U.S. government corporations and agencies
ASSETS
Securities available-for-sale, at fair value	0	0
Fair Value Measurements, Recurring | Level 1 | Residential mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Securities available-for-sale, at fair value	0	0
Fair Value Measurements, Recurring | Level 1 | Commercial mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Securities available-for-sale, at fair value	0	0
Fair Value Measurements, Recurring | Level 1 | Obligations of states and political subdivisions
ASSETS
Securities available-for-sale, at fair value	0	0
Fair Value Measurements, Recurring | Level 1 | Marketable equity securities
ASSETS
Securities available-for-sale, at fair value	0	0
Fair Value Measurements, Recurring | Level 1 | Interest Rate Swap
ASSETS
Derivative financial assets	0	0
LIABILITIES
Derivative financial liabilities	0	0
Fair Value Measurements, Recurring | Level 1 | Interest Rate Lock Commitments
ASSETS
Derivative financial assets	0	0
Fair Value Measurements, Recurring | Level 1 | Forward Sale Contracts
LIABILITIES
Derivative financial liabilities	0	0
Fair Value Measurements, Recurring | Level 2
ASSETS
Securities available-for-sale, at fair value	693,487	660,963
Trading securities held in a Rabbi Trust	0	0
Total securities	693,487	660,963
Total Assets	700,683	672,519
LIABILITIES
Total Liabilities	6,985	11,281
Fair Value Measurements, Recurring | Level 2 | U.S. Treasury securities
ASSETS
Securities available-for-sale, at fair value	24,811	14,941
Fair Value Measurements, Recurring | Level 2 | Obligations of U.S. government corporations and agencies
ASSETS
Securities available-for-sale, at fair value	232,179	263,303
Fair Value Measurements, Recurring | Level 2 | Collateralized mortgage obligations of U.S. government corporations and agencies
ASSETS
Securities available-for-sale, at fair value	129,777	128,835
Fair Value Measurements, Recurring | Level 2 | Residential mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Securities available-for-sale, at fair value	37,358	40,125
Fair Value Measurements, Recurring | Level 2 | Commercial mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Securities available-for-sale, at fair value	125,604	69,204
Fair Value Measurements, Recurring | Level 2 | Obligations of states and political subdivisions
ASSETS
Securities available-for-sale, at fair value	132,509	134,886
Fair Value Measurements, Recurring | Level 2 | Marketable equity securities
ASSETS
Securities available-for-sale, at fair value	11,249	9,669
Fair Value Measurements, Recurring | Level 2 | Interest Rate Swap
ASSETS
Derivative financial assets	6,960	11,295
LIABILITIES
Derivative financial liabilities	6,958	11,276
Fair Value Measurements, Recurring | Level 2 | Interest Rate Lock Commitments
ASSETS
Derivative financial assets	236	261
Fair Value Measurements, Recurring | Level 2 | Forward Sale Contracts
LIABILITIES
Derivative financial liabilities	27	5
Fair Value Measurements, Recurring | Level 3
ASSETS
Trading securities held in a Rabbi Trust	0	0
Fair Value Measurements, Recurring | Level 3 | U.S. Treasury securities
ASSETS
Securities available-for-sale, at fair value	0	0
Fair Value Measurements, Recurring | Level 3 | Obligations of U.S. government corporations and agencies
ASSETS
Securities available-for-sale, at fair value	0	0
Fair Value Measurements, Recurring | Level 3 | Collateralized mortgage obligations of U.S. government corporations and agencies
ASSETS
Securities available-for-sale, at fair value	0	0
Fair Value Measurements, Recurring | Level 3 | Residential mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Securities available-for-sale, at fair value	0	0
Fair Value Measurements, Recurring | Level 3 | Commercial mortgage-backed securities of U.S. government corporations and agencies
ASSETS
Securities available-for-sale, at fair value	0	0
Fair Value Measurements, Recurring | Level 3 | Obligations of states and political subdivisions
ASSETS
Securities available-for-sale, at fair value	0	0
Fair Value Measurements, Recurring | Level 3 | Marketable equity securities
ASSETS
Securities available-for-sale, at fair value	0	0
Fair Value Measurements, Recurring | Level 3 | Interest Rate Swap
ASSETS
Derivative financial assets	0	0
LIABILITIES
Derivative financial liabilities	0	0
Fair Value Measurements, Recurring | Level 3 | Interest Rate Lock Commitments
ASSETS
Derivative financial assets	0	0
Fair Value Measurements, Recurring | Level 3 | Forward Sale Contracts
LIABILITIES
Derivative financial liabilities	$ 0	$ 0

Fair Value Measurements - Ass65

Fair Value Measurements - Assets Measured at Estimated Fair Value on Nonrecurring Basis by Fair Value Hierarchy (Details) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities measured at fair value on nonrecurring basis	$ 0	$ 0
Fair Value, Measurements, Nonrecurring
ASSETS
Loans held for sale	1,802,000	0
Impaired loans	10,329,000	9,373,000
Other real estate owned	396,000	158,000
Mortgage servicing rights	4,098,000	3,396,000
Total Assets	16,625,000	12,927,000
Fair Value, Measurements, Nonrecurring | Level 1
ASSETS
Loans held for sale	0	0
Impaired loans	0	0
Other real estate owned	0	0
Mortgage servicing rights	0	0
Total Assets	0	0
Fair Value, Measurements, Nonrecurring | Level 2
ASSETS
Loans held for sale	0	0
Impaired loans	0	0
Other real estate owned	0	0
Mortgage servicing rights	0	0
Total Assets	0	0
Fair Value, Measurements, Nonrecurring | Level 3
ASSETS
Loans held for sale	1,802,000	0
Impaired loans	10,329,000	9,373,000
Other real estate owned	396,000	158,000
Mortgage servicing rights	4,098,000	3,396,000
Total Assets	$ 16,625,000	$ 12,927,000

Fair Value Measurements - Carry

Fair Value Measurements - Carrying Values and Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
ASSETS
Securities available-for-sale, at fair value	$ 693,487	$ 660,963
FHLB and other restricted stock	31,817	23,032
LIABILITIES
Junior subordinated debt securities	45,619	45,619	$ 45,619
Carrying Value
ASSETS
Cash and due from banks, including interest-bearing deposits	139,486	99,399
Securities available-for-sale, at fair value	693,487	660,963
Loans held for sale	3,793	35,321
Portfolio loans, net of unearned income	5,611,419	5,027,612
Bank owned life insurance	72,081	70,175
FHLB and other restricted stock	31,817	23,032
Trading securities held in a Rabbi Trust	4,410	4,021
Mortgage servicing rights	3,744	3,237
LIABILITIES
Deposits	5,272,377	4,876,611
Securities sold under repurchase agreements	50,832	62,086
Short-term borrowings	660,000	356,000
Long-term borrowings	14,713	117,043
Junior subordinated debt securities	45,619	45,619
Carrying Value | Interest Rate Swap
ASSETS
Derivative financial assets	6,960	11,295
LIABILITIES
Derivative financial liabilities	6,958	11,276
Carrying Value | Interest Rate Lock Commitments
ASSETS
Derivative financial assets	236	261
Carrying Value | Forward Sale Contracts
LIABILITIES
Derivative financial liabilities	27	5
Fair Value Measurements
ASSETS
Cash and due from banks, including interest-bearing deposits	139,486	99,399
Securities available-for-sale, at fair value	693,487	660,963
Loans held for sale	3,815	35,500
Portfolio loans, net of unearned income	5,551,266	5,001,004
Bank owned life insurance	72,081	70,175
FHLB and other restricted stock	31,817	23,032
Trading securities held in a Rabbi Trust	4,410	4,021
Mortgage servicing rights	4,098	3,396
LIABILITIES
Deposits	5,276,499	4,881,718
Securities sold under repurchase agreements	50,832	62,086
Short-term borrowings	660,000	356,000
Long-term borrowings	15,267	117,859
Junior subordinated debt securities	45,619	45,619
Fair Value Measurements | Interest Rate Swap
ASSETS
Derivative financial assets	6,960	11,295
LIABILITIES
Derivative financial liabilities	6,958	11,276
Fair Value Measurements | Interest Rate Lock Commitments
ASSETS
Derivative financial assets	236	261
Fair Value Measurements | Forward Sale Contracts
LIABILITIES
Derivative financial liabilities	27	5
Fair Value Measurements | Level 1
ASSETS
Cash and due from banks, including interest-bearing deposits	139,486	99,399
Trading securities held in a Rabbi Trust	4,410	4,021
Fair Value Measurements | Level 2
ASSETS
Securities available-for-sale, at fair value	693,487	660,963
Bank owned life insurance	72,081	70,175
Fair Value Measurements | Level 2 | Interest Rate Swap
ASSETS
Derivative financial assets	6,960	11,295
LIABILITIES
Derivative financial liabilities	6,958	11,276
Fair Value Measurements | Level 2 | Interest Rate Lock Commitments
ASSETS
Derivative financial assets	236	261
Fair Value Measurements | Level 2 | Forward Sale Contracts
LIABILITIES
Derivative financial liabilities	27	5
Fair Value Measurements | Level 3
ASSETS
Loans held for sale	3,815	35,500
Portfolio loans, net of unearned income	5,551,266	5,001,004
FHLB and other restricted stock	31,817	23,032
Mortgage servicing rights	4,098	3,396
LIABILITIES
Deposits	5,276,499	4,881,718
Securities sold under repurchase agreements	50,832	62,086
Short-term borrowings	660,000	356,000
Long-term borrowings	15,267	117,859
Junior subordinated debt securities	$ 45,619	$ 45,619

Restrictions on Cash and Due 67

Restrictions on Cash and Due from Bank Accounts - Additional Information (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash and Cash Equivalents [Abstract]
Restricted Cash and Cash Equivalents	$ 36.8	$ 44.1	$ 41.8

Dividend and Loan Restrictions

Dividend and Loan Restrictions - Additional Information (Details)	12 Months Ended
	Dec. 31, 2016
Equity [Abstract]
Percentage of collateralized loans	10.00%

Securities Available-for-Sale -

Securities Available-for-Sale - Composition of Securities Available-for-Sale (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 686,205	$ 650,782
Gross Unrealized Gains	10,754	11,897
Gross Unrealized Losses	(3,472)	(1,716)
Fair Value	693,487	660,963
U.S. Treasury securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	24,891	14,914
Gross Unrealized Gains	47	27
Gross Unrealized Losses	(127)	0
Fair Value	24,811	14,941
Obligations of U.S. government corporations and agencies
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	230,989	262,045
Gross Unrealized Gains	1,573	1,825
Gross Unrealized Losses	(383)	(567)
Fair Value	232,179	263,303
Collateralized mortgage obligations of U.S. government corporations and agencies
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	130,046	128,458
Gross Unrealized Gains	465	693
Gross Unrealized Losses	(734)	(316)
Fair Value	129,777	128,835
Residential mortgage-backed securities of U.S. government corporations and agencies
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	36,606	39,185
Gross Unrealized Gains	984	1,091
Gross Unrealized Losses	(232)	(151)
Fair Value	37,358	40,125
Commercial mortgage-backed securities of U.S. government corporations and agencies
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	127,311	69,697
Gross Unrealized Gains	243	183
Gross Unrealized Losses	(1,950)	(676)
Fair Value	125,604	69,204
Obligations of states and political subdivisions
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	128,783	128,904
Gross Unrealized Gains	3,772	5,988
Gross Unrealized Losses	(46)	(6)
Fair Value	132,509	134,886
Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	678,626	643,203
Gross Unrealized Gains	7,084	9,807
Gross Unrealized Losses	(3,472)	(1,716)
Fair Value	682,238	651,294
Marketable equity securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	7,579	7,579
Gross Unrealized Gains	3,670	2,090
Gross Unrealized Losses	0	0
Fair Value	$ 11,249	$ 9,669

Securities Available-for-Sale70

Securities Available-for-Sale - Schedule of Gross and Net Realized Gains and Losses on Sale of Securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Investments, Debt and Equity Securities [Abstract]
Gross realized gains	$ 0	$ 0	$ 41
Gross realized losses	0	(34)	0
Net Realized Gains	$ 0	$ (34)	$ 41

Securities Available-for-Sale71

Securities Available-for-Sale - Fair Value and Age of Gross Unrealized Losses by Investment Category (Details)	Dec. 31, 2016USD ($)security	Dec. 31, 2015USD ($)security
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Number of Positions | security	31	23
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 267,500,000	$ 213,997,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Unrealized Losses	$ (3,472,000)	$ (1,302,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Number of Positions | security	0	3
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	$ 0	$ 24,014,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Unrealized Losses	$ 0	$ (414,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Number of Positions | security	31	26
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	$ 267,500,000	$ 238,011,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Unrealized Losses, Total	$ (3,472,000)	$ (1,716,000)
U.S. Treasury securities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Number of Positions | security	1	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 9,811,000	$ 0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Unrealized Losses	$ (127,000)	$ 0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Number of Positions | security	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	$ 0	$ 0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Unrealized Losses	$ 0	$ 0
Available-for-sale Securities, Continuous Unrealized Loss Position, Number of Positions | security	1	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	$ 9,811,000	$ 0
Available-for-sale Securities, Continuous Unrealized Loss Position, Unrealized Losses, Total	$ (127,000)	$ 0
Obligations of U.S. government corporations and agencies
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Number of Positions | security	7	10
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 62,483,000	$ 88,584,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Unrealized Losses	$ (383,000)	$ (379,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Number of Positions | security	0	2
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	$ 0	$ 14,542,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Unrealized Losses	$ 0	$ (188,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Number of Positions | security	7	12
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	$ 62,483,000	$ 103,126,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Unrealized Losses, Total	$ (383,000)	$ (567,000)
Collateralized mortgage obligations of U.S. government corporations and agencies
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Number of Positions | security	10	6
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 83,031,000	$ 61,211,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Unrealized Losses	$ (734,000)	$ (316,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Number of Positions | security	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	$ 0	$ 0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Unrealized Losses	$ 0	$ 0
Available-for-sale Securities, Continuous Unrealized Loss Position, Number of Positions | security	10	6
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	$ 83,031,000	$ 61,211,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Unrealized Losses, Total	$ (734,000)	$ (316,000)
Residential mortgage-backed securities of U.S. government corporations and agencies
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Number of Positions | security	2	1
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 10,022,000	$ 7,993,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Unrealized Losses	$ (232,000)	$ (151,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Number of Positions | security	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	$ 0	$ 0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Unrealized Losses	$ 0	$ 0
Available-for-sale Securities, Continuous Unrealized Loss Position, Number of Positions | security	2	1
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	$ 10,022,000	$ 7,993,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Unrealized Losses, Total	$ (232,000)	$ (151,000)
Commercial mortgage-backed securities of U.S. government corporations and agencies
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Number of Positions | security	10	5
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 96,576,000	$ 50,839,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Unrealized Losses	$ (1,950,000)	$ (450,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Number of Positions | security	0	1
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	$ 0	$ 9,472,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Unrealized Losses	$ 0	$ (226,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Number of Positions | security	10	6
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	$ 96,576,000	$ 60,311,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Unrealized Losses, Total	$ (1,950,000)	$ (676,000)
Obligations of states and political subdivisions
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Number of Positions | security	1	1
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 5,577,000	$ 5,370,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Unrealized Losses	$ (46,000)	$ (6,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Number of Positions | security	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	$ 0	$ 0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Unrealized Losses	$ 0	$ 0
Available-for-sale Securities, Continuous Unrealized Loss Position, Number of Positions | security	1	1
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	$ 5,577,000	$ 5,370,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Unrealized Losses, Total	$ (46,000)	$ (6,000)
Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Number of Positions | security	31	23
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 267,500,000	$ 213,997,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Unrealized Losses	$ (3,472,000)	$ (1,302,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Number of Positions | security	0	3
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	$ 0	$ 24,014,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Unrealized Losses	$ 0	$ (414,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Number of Positions | security	31	26
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	$ 267,500,000	$ 238,011,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Unrealized Losses, Total	$ (3,472,000)	$ (1,716,000)
Marketable equity securities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Number of Positions | security	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 0	$ 0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Unrealized Losses	$ 0	$ 0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Number of Positions | security	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	$ 0	$ 0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Unrealized Losses	$ 0	$ 0
Available-for-sale Securities, Continuous Unrealized Loss Position, Number of Positions | security	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	$ 0	$ 0
Available-for-sale Securities, Continuous Unrealized Loss Position, Unrealized Losses, Total	$ 0	$ 0

Securities Available-for-Sale72

Securities Available-for-Sale - Additional Information (Details)	Dec. 31, 2016USD ($)security	Dec. 31, 2015USD ($)
Schedule of Available-for-sale Securities [Line Items]
Number of debt securities on which unrealized losses were primarily attributable to changes in interest | security	31
Unrealized losses on marketable securities	$ 3,472,000	$ 1,716,000
Carrying values of securities	342,000,000	278,400,000
Marketable equity securities
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses on marketable securities	$ 0	$ 0

Securities Available-for-Sale73

Securities Available-for-Sale - Unrealized Gains (Losses) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Total unrealized gains/(losses) on securities available for sale, Gross Unrealized Gains	$ 10,754	$ 11,897
Total unrealized gains/(losses) on securities available for sale, Gross Unrealized Losses	(3,472)	(1,716)
Total unrealized gains/(losses) on securities available for sale, Net Unrealized Gains	7,282	10,181
Income tax expense/(benefit), Gross Unrealized Gains	(3,776)	(4,164)
Income tax expense/(benefit), Gross Unrealized Losses	1,219	601
Income tax expense/(benefit), Net Unrealized Gains	(2,557)	(3,563)
Net unrealized gains/(losses), net of tax included in accumulated other comprehensive income/(loss)	6,978	7,733
Net unrealized gains/(losses), net of tax included in accumulated other comprehensive income/(loss)	(2,253)	(1,115)
Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	$ 4,725	$ 6,618

Securities Available-for-Sale74

Securities Available-for-Sale - Amortized Cost and Fair Value of Available-for-Sale Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 686,205	$ 650,782
Fair Value	693,487	660,963
Obligations of U.S. government corporations and agencies
Schedule of Available-for-sale Securities [Line Items]
Due in one year or less, Amortized Cost	52,594
Due after one year through five years, Amortized Cost	201,450
Due after five years through ten years, Amortized Cost	64,569
Due after ten years, Amortized Cost	66,050
Available-for-sale Securities, Debt Maturities, Amortized Cost	384,663
Due in one year or less, Fair Value	52,696
Due after one year through five years, Fair Value	203,513
Due after five years through ten years, Fair Value	64,975
Due after ten years, Fair Value	68,315
Fair Value, Debt securities	389,499
Collateralized mortgage obligations of U.S. government corporations and agencies
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	130,046	128,458
Fair Value	129,777	128,835
Residential mortgage-backed securities of U.S. government corporations and agencies
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	36,606	39,185
Fair Value	37,358	40,125
Commercial mortgage-backed securities of U.S. government corporations and agencies
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	127,311	69,697
Fair Value	125,604	69,204
Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	678,626	643,203
Fair Value	682,238	651,294
Marketable equity securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	7,579	7,579
Fair Value	$ 11,249	$ 9,669

Loans and Loans Held for Sale -

Loans and Loans Held for Sale - Additional Information (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2015USD ($)	Dec. 31, 2016USD ($)loan	Dec. 31, 2015USD ($)loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, net of deferred income		$ 5,200	$ 3,200
Unamortized discount related to purchase accounting fair value adjustments		7,100	10,900
Loans		5,615,212	5,062,933
Portfolio loans, net of unearned income		5,611,419	$ 5,027,612
Decrease in loans held-for-sale during period		$ 31,500
Number of loan modified | loan		18
Number of commitments to lend additional funds on TDRs | loan		1
Commitment to lend additional funds on TDRs		$ 800
Number of TDRs returned back to accruing status | loan		5	8
Financial receivable trouble debt restructuring reclassified to accruing trouble debt restructuring status		$ 900	$ 400
Minimum period of loan payment defaults following restructure for TDRs to be in default		90 days
Number of defaulted TDRs that were restructured withing twelve months prior to defaulting | loan		0	0
Increase in nonperforming assets		$ 7,600
Nonperforming assets		$ 43,314	$ 35,736
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of commercial loans in total portfolio loans		78.00%	76.00%
Loans and leases receivable, gross		$ 4,355,395	$ 3,836,877
Portfolio loans, net of unearned income		4,355,395	3,836,877
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans		2,498,476	2,166,603
Portfolio loans, net of unearned income		$ 2,498,476	2,166,603
Number of loan modified | loan		3
Loans modified not considered to be troubled debt restructuring		$ 3,100
Commercial Real Estate | Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, gross		2,498,476	2,166,603
Portfolio loans, net of unearned income		2,498,476	2,166,603
Commercial and Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans		1,401,035	1,256,830
Portfolio loans, net of unearned income		$ 1,401,035	1,256,830
Number of loan modified | loan		15
Loans modified not considered to be troubled debt restructuring		$ 25,600
Commercial and Industrial | Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, gross		1,401,035	1,256,830
Portfolio loans, net of unearned income		1,401,035	1,256,830
Commercial Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans		455,884	413,444
Portfolio loans, net of unearned income		455,884	413,444
Commercial Construction | Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, gross		455,884	413,444
Portfolio loans, net of unearned income		455,884	413,444
Residential Mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans		701,982	639,372
Portfolio loans, net of unearned income		1,190,172	1,116,796
Home Equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans		482,284	470,845
Installment and Other Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Decrease in loans held-for-sale during period	$ (25,000)
Gain on sale of credit card portfolio			2,100
Consumer Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans		$ 5,906	$ 6,579
CRE and Commercial Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Out-of-state exposure of combined portfolio		5.20%	5.80%
Percentage of total loans out-of-state		2.70%	3.00%
CRE and Commercial Construction | Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, gross		$ 3,000,000
Combined percentage of commercial real estate and commercial construction in total commercial loans		68.00%	67.00%
Combined percentage of commercial real estate and commercial construction in total portfolio loans		53.00%	51.00%
Portfolio loans, net of unearned income			$ 2,600,000
Concentration risk percentage		0.00%	0.00%
Maximum concentration of commercial real estate and commercial construction portfolio in loans		7.00%	7.00%
Integrity Bancshares, Inc.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans		$ 543,300	$ 673,300
Nonperforming assets, assumed in business acquisitions		16,900
Integrity Bancshares, Inc. | Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans		273,000	293,200
Integrity Bancshares, Inc. | Commercial and Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans		140,800	167,700
Integrity Bancshares, Inc. | Commercial Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans		33,500	69,200
Integrity Bancshares, Inc. | Residential Mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans		74,000	115,600
Integrity Bancshares, Inc. | Home Equity, Installment and Other Consumer Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans		$ 22,000	$ 27,500

Loans and Loans Held for Sale76

Loans and Loans Held for Sale - Composition of Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Composition of Loans
Portfolio loans, net of unearned income	$ 5,611,419	$ 5,027,612
Loans held for sale	3,793	35,321
Total Loans	5,615,212	5,062,933
Commercial Real Estate
Composition of Loans
Portfolio loans, net of unearned income	2,498,476	2,166,603
Total Loans	2,498,476	2,166,603
Commercial and Industrial
Composition of Loans
Portfolio loans, net of unearned income	1,401,035	1,256,830
Total Loans	1,401,035	1,256,830
Commercial Construction
Composition of Loans
Portfolio loans, net of unearned income	455,884	413,444
Total Loans	455,884	413,444
Residential Mortgage
Composition of Loans
Portfolio loans, net of unearned income	1,190,172	1,116,796
Total Loans	701,982	639,372
Home Equity
Composition of Loans
Total Loans	482,284	470,845
Installment and Other Consumer
Composition of Loans
Total Loans	65,852	73,939
Consumer Construction
Composition of Loans
Total Loans	5,906	6,579
Commercial
Composition of Loans
Portfolio loans, net of unearned income	4,355,395	3,836,877
Commercial | Commercial Real Estate
Composition of Loans
Portfolio loans, net of unearned income	2,498,476	2,166,603
Commercial | Commercial and Industrial
Composition of Loans
Portfolio loans, net of unearned income	1,401,035	1,256,830
Commercial | Commercial Construction
Composition of Loans
Portfolio loans, net of unearned income	455,884	413,444
Consumer
Composition of Loans
Portfolio loans, net of unearned income	1,256,024	1,190,735
Consumer | Residential Mortgage
Composition of Loans
Portfolio loans, net of unearned income	701,982	639,372
Consumer | Home Equity
Composition of Loans
Portfolio loans, net of unearned income	482,284	470,845
Consumer | Installment and Other Consumer
Composition of Loans
Portfolio loans, net of unearned income	65,852	73,939
Consumer | Consumer Construction
Composition of Loans
Portfolio loans, net of unearned income	$ 5,906	$ 6,579

Loans and Loans Held for Sale77

Loans and Loans Held for Sale - Restructured Loans for Periods Presented (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Modifications [Line Items]
Restructured loans	$ 12,192	$ 6,338
Performing TDRs
Financing Receivable, Modifications [Line Items]
Restructured loans	13,423	23,955
Performing TDRs | Commercial Real Estate
Financing Receivable, Modifications [Line Items]
Restructured loans	2,994	6,822
Performing TDRs | Commercial and Industrial
Financing Receivable, Modifications [Line Items]
Restructured loans	1,387	6,321
Performing TDRs | Commercial Construction
Financing Receivable, Modifications [Line Items]
Restructured loans	2,966	5,013
Performing TDRs | Residential Mortgage
Financing Receivable, Modifications [Line Items]
Restructured loans	2,375	2,590
Performing TDRs | Home Equity
Financing Receivable, Modifications [Line Items]
Restructured loans	3,683	3,184
Performing TDRs | Installment and Other Consumer
Financing Receivable, Modifications [Line Items]
Restructured loans	18	25
Nonperforming TDRs
Financing Receivable, Modifications [Line Items]
Restructured loans	11,598	7,659
Nonperforming TDRs | Commercial Real Estate
Financing Receivable, Modifications [Line Items]
Restructured loans	646	3,548
Nonperforming TDRs | Commercial and Industrial
Financing Receivable, Modifications [Line Items]
Restructured loans	4,493	1,570
Nonperforming TDRs | Commercial Construction
Financing Receivable, Modifications [Line Items]
Restructured loans	430	1,265
Nonperforming TDRs | Residential Mortgage
Financing Receivable, Modifications [Line Items]
Restructured loans	5,068	665
Nonperforming TDRs | Home Equity
Financing Receivable, Modifications [Line Items]
Restructured loans	954	523
Nonperforming TDRs | Installment and Other Consumer
Financing Receivable, Modifications [Line Items]
Restructured loans	7	88
Total TDRs
Financing Receivable, Modifications [Line Items]
Restructured loans	25,021	31,614
Total TDRs | Commercial Real Estate
Financing Receivable, Modifications [Line Items]
Restructured loans	3,640	10,370
Total TDRs | Commercial and Industrial
Financing Receivable, Modifications [Line Items]
Restructured loans	5,880	7,891
Total TDRs | Commercial Construction
Financing Receivable, Modifications [Line Items]
Restructured loans	3,396	6,278
Total TDRs | Residential Mortgage
Financing Receivable, Modifications [Line Items]
Restructured loans	7,443	3,255
Total TDRs | Home Equity
Financing Receivable, Modifications [Line Items]
Restructured loans	4,637	3,707
Total TDRs | Installment and Other Consumer
Financing Receivable, Modifications [Line Items]
Restructured loans	$ 25	$ 113

Loans and Loans Held for Sale78

Loans and Loans Held for Sale - Restructured Loans for Periods Stated (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)loan	Dec. 31, 2015USD ($)loan
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	53	60
Pre-Modification Outstanding Recorded Investment	$ 14,074	$ 8,290
Post-Modification Outstanding Recorded Investment	12,192	6,338
Total Difference in Recorded Investment	$ (1,882)	$ (1,952)
Principal Deferral
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	7	8
Pre-Modification Outstanding Recorded Investment	$ 4,305	$ 3,512
Post-Modification Outstanding Recorded Investment	4,164	2,204
Total Difference in Recorded Investment	$ (141)	$ (1,308)
Interest Rate Reduction
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	1
Pre-Modification Outstanding Recorded Investment	$ 250
Post-Modification Outstanding Recorded Investment	242
Total Difference in Recorded Investment	$ (8)
Maturity Date Extension and Interest Rate Reduction
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	3	4
Pre-Modification Outstanding Recorded Investment	$ 884	$ 410
Post-Modification Outstanding Recorded Investment	877	406
Total Difference in Recorded Investment	$ (7)	$ (4)
Maturity Date Extension
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	13	17
Pre-Modification Outstanding Recorded Investment	$ 6,795	$ 3,312
Post-Modification Outstanding Recorded Investment	5,197	2,922
Total Difference in Recorded Investment	$ (1,598)	$ (390)
Chapter 7 Bankruptcy
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	29	31
Pre-Modification Outstanding Recorded Investment	$ 1,840	$ 1,056
Post-Modification Outstanding Recorded Investment	1,712	806
Total Difference in Recorded Investment	$ (128)	$ (250)
Commercial Real Estate | Principal Deferral
Financing Receivable, Modifications [Line Items]
Number of Loans | loan		2
Pre-Modification Outstanding Recorded Investment		$ 2,851
Post-Modification Outstanding Recorded Investment		1,841
Total Difference in Recorded Investment		$ (1,010)
Commercial Real Estate | Interest Rate Reduction
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	1
Pre-Modification Outstanding Recorded Investment	$ 250
Post-Modification Outstanding Recorded Investment	242
Total Difference in Recorded Investment	$ (8)
Commercial Real Estate | Maturity Date Extension
Financing Receivable, Modifications [Line Items]
Number of Loans | loan		3
Pre-Modification Outstanding Recorded Investment		$ 438
Post-Modification Outstanding Recorded Investment		427
Total Difference in Recorded Investment		$ (11)
Commercial Real Estate | Chapter 7 Bankruptcy
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	1
Pre-Modification Outstanding Recorded Investment	$ 709
Post-Modification Outstanding Recorded Investment	646
Total Difference in Recorded Investment	$ (63)
Commercial and Industrial | Principal Deferral
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	5	6
Pre-Modification Outstanding Recorded Investment	$ 985	$ 661
Post-Modification Outstanding Recorded Investment	986	363
Total Difference in Recorded Investment	$ 1	$ (298)
Commercial and Industrial | Maturity Date Extension
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	4	2
Pre-Modification Outstanding Recorded Investment	$ 4,756	$ 824
Post-Modification Outstanding Recorded Investment	3,334	728
Total Difference in Recorded Investment	$ (1,422)	$ (96)
Commercial Construction | Maturity Date Extension
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	3	3
Pre-Modification Outstanding Recorded Investment	$ 1,251	$ 1,434
Post-Modification Outstanding Recorded Investment	1,151	1,432
Total Difference in Recorded Investment	$ (100)	$ (2)
Residential Mortgage | Principal Deferral
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	1
Pre-Modification Outstanding Recorded Investment	$ 3,273
Post-Modification Outstanding Recorded Investment	3,133
Total Difference in Recorded Investment	$ (140)
Residential Mortgage | Maturity Date Extension and Interest Rate Reduction
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	1	1
Pre-Modification Outstanding Recorded Investment	$ 280	$ 207
Post-Modification Outstanding Recorded Investment	279	205
Total Difference in Recorded Investment	$ (1)	$ (2)
Residential Mortgage | Maturity Date Extension
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	1	8
Pre-Modification Outstanding Recorded Investment	$ 483	$ 545
Post-Modification Outstanding Recorded Investment	414	265
Total Difference in Recorded Investment	$ (69)	$ (280)
Residential Mortgage | Chapter 7 Bankruptcy
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	7	7
Pre-Modification Outstanding Recorded Investment	$ 439	$ 428
Post-Modification Outstanding Recorded Investment	413	226
Total Difference in Recorded Investment	$ (26)	$ (202)
Home Equity | Principal Deferral
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	1
Pre-Modification Outstanding Recorded Investment	$ 47
Post-Modification Outstanding Recorded Investment	45
Total Difference in Recorded Investment	$ (2)
Home Equity | Maturity Date Extension and Interest Rate Reduction
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	2	3
Pre-Modification Outstanding Recorded Investment	$ 604	$ 203
Post-Modification Outstanding Recorded Investment	598	201
Total Difference in Recorded Investment	$ (6)	$ (2)
Home Equity | Maturity Date Extension
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	5	1
Pre-Modification Outstanding Recorded Investment	$ 305	$ 71
Post-Modification Outstanding Recorded Investment	298	70
Total Difference in Recorded Investment	$ (7)	$ (1)
Home Equity | Chapter 7 Bankruptcy
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	19	23
Pre-Modification Outstanding Recorded Investment	$ 676	$ 619
Post-Modification Outstanding Recorded Investment	643	576
Total Difference in Recorded Investment	$ (33)	$ (43)
Installment and Other Consumer | Chapter 7 Bankruptcy
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	2	1
Pre-Modification Outstanding Recorded Investment	$ 16	$ 9
Post-Modification Outstanding Recorded Investment	10	4
Total Difference in Recorded Investment	$ (6)	$ (5)

Loans and Loans Held for Sale79

Loans and Loans Held for Sale - Summary of Nonperforming Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Nonperforming Assets
Nonaccrual loans	$ 31,037	$ 27,723
Nonaccrual TDRs	11,598	7,659
Total nonaccrual loans	42,635	35,382
OREO	679	354
Total Nonperforming Assets	$ 43,314	$ 35,736

Loans and Loans Held for Sale80

Loans and Loans Held for Sale - Summary of Aggregate Amount of Loans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Loans Receivable from Officers and Directors [Roll Forward]
Balance at beginning of year	$ 24,517	$ 27,368
New loans	22,740	24,743
Repayments	(22,090)	(27,594)
Balance at End of Year	$ 25,167	$ 24,517

Allowance for Loan Losses - Age

Allowance for Loan Losses - Age Analysis of Past Due Loans Segregated by Class of Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Current	$ 5,563,123	$ 5,002,925
Loans, Past Due	52,089	60,008
Non-performing loans	42,635	35,382
Total Loans	5,615,212	5,062,933
Commercial Real Estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Current	2,479,513	2,145,655
Loans, Past Due	18,963	20,948
Non-performing loans	16,172	8,719
Total Loans	2,498,476	2,166,603
Commercial and Industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Current	1,391,475	1,244,802
Loans, Past Due	9,560	12,028
Non-performing loans	8,071	9,279
Total Loans	1,401,035	1,256,830
Commercial Construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Current	450,410	401,084
Loans, Past Due	5,474	12,360
Non-performing loans	4,927	8,753
Total Loans	455,884	413,444
Residential Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Current	689,635	631,085
Loans, Past Due	12,347	8,287
Non-performing loans	9,918	5,629
Total Loans	701,982	639,372
Home Equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Current	476,866	465,055
Loans, Past Due	5,418	5,790
Non-performing loans	3,439	2,902
Total Loans	482,284	470,845
Installment and Other Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Current	65,525	73,486
Loans, Past Due	327	453
Non-performing loans	108	100
Total Loans	65,852	73,939
Consumer Construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Current	5,906	6,579
Loans, Past Due	0	0
Non-performing loans	0	0
Total Loans	5,906	6,579
Loans Held for Sale
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Current	3,793	35,179
Loans, Past Due	0	142
Non-performing loans	0	0
Total Loans	3,793	35,321
30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Past Due	6,598	22,001
30-59 Days Past Due | Commercial Real Estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Past Due	2,032	11,602
30-59 Days Past Due | Commercial and Industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Past Due	1,061	2,453
30-59 Days Past Due | Commercial Construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Past Due	547	3,517
30-59 Days Past Due | Residential Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Past Due	1,312	1,728
30-59 Days Past Due | Home Equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Past Due	1,470	2,365
30-59 Days Past Due | Installment and Other Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Past Due	176	242
30-59 Days Past Due | Consumer Construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Past Due	0	0
30-59 Days Past Due | Loans Held for Sale
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Past Due	0	94
60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Past Due	2,856	2,625
60-89 Days Past Due | Commercial Real Estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Past Due	759	627
60-89 Days Past Due | Commercial and Industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Past Due	428	296
60-89 Days Past Due | Commercial Construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Past Due	0	90
60-89 Days Past Due | Residential Mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Past Due	1,117	930
60-89 Days Past Due | Home Equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Past Due	509	523
60-89 Days Past Due | Installment and Other Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Past Due	43	111
60-89 Days Past Due | Consumer Construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Past Due	0	0
60-89 Days Past Due | Loans Held for Sale
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, Past Due	$ 0	$ 48

Allowance for Loan Losses - Rec

Allowance for Loan Losses - Recorded Investment in Commercial Loan Classes by Internally Assigned Risk Ratings (Details) - Commercial - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Total recorded investment in commercial loan	$ 4,355,395	$ 3,836,877
Total percentage of recorded investment in commercial loan	100.00%	100.00%
Pass
Financing Receivable, Recorded Investment [Line Items]
Total recorded investment in commercial loan	$ 4,169,721	$ 3,653,344
Total percentage of recorded investment in commercial loan	95.70%	95.20%
Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total recorded investment in commercial loan	$ 88,198	$ 83,680
Total percentage of recorded investment in commercial loan	2.00%	2.20%
Substandard
Financing Receivable, Recorded Investment [Line Items]
Total recorded investment in commercial loan	$ 97,476	$ 99,853
Total percentage of recorded investment in commercial loan	2.30%	2.60%
Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total recorded investment in commercial loan	$ 2,498,476	$ 2,166,603
Total percentage of recorded investment in commercial loan	100.00%	100.00%
Commercial Real Estate | Pass
Financing Receivable, Recorded Investment [Line Items]
Total recorded investment in commercial loan	$ 2,423,742	$ 2,094,851
Total percentage of recorded investment in commercial loan	97.00%	96.70%
Commercial Real Estate | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total recorded investment in commercial loan	$ 33,098	$ 19,938
Total percentage of recorded investment in commercial loan	1.30%	0.90%
Commercial Real Estate | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total recorded investment in commercial loan	$ 41,636	$ 51,814
Total percentage of recorded investment in commercial loan	1.70%	2.40%
Commercial and Industrial
Financing Receivable, Recorded Investment [Line Items]
Total recorded investment in commercial loan	$ 1,401,035	$ 1,256,830
Total percentage of recorded investment in commercial loan	100.00%	100.00%
Commercial and Industrial | Pass
Financing Receivable, Recorded Investment [Line Items]
Total recorded investment in commercial loan	$ 1,315,507	$ 1,182,685
Total percentage of recorded investment in commercial loan	93.90%	94.10%
Commercial and Industrial | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total recorded investment in commercial loan	$ 40,409	$ 43,896
Total percentage of recorded investment in commercial loan	2.90%	3.50%
Commercial and Industrial | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total recorded investment in commercial loan	$ 45,119	$ 30,249
Total percentage of recorded investment in commercial loan	3.20%	2.40%
Commercial Construction
Financing Receivable, Recorded Investment [Line Items]
Total recorded investment in commercial loan	$ 455,884	$ 413,444
Total percentage of recorded investment in commercial loan	100.00%	100.00%
Commercial Construction | Pass
Financing Receivable, Recorded Investment [Line Items]
Total recorded investment in commercial loan	$ 430,472	$ 375,808
Total percentage of recorded investment in commercial loan	94.40%	90.90%
Commercial Construction | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total recorded investment in commercial loan	$ 14,691	$ 19,846
Total percentage of recorded investment in commercial loan	3.20%	4.80%
Commercial Construction | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total recorded investment in commercial loan	$ 10,721	$ 17,790
Total percentage of recorded investment in commercial loan	2.40%	4.30%

Allowance for Loan Losses - R83

Allowance for Loan Losses - Recorded Investment in Consumer Loan Classes by Performing and Nonperforming Status (Details) - Consumer - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	$ 1,256,024	$ 1,190,735
% of Total	100.00%	100.00%
Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	$ 1,242,559	$ 1,182,104
% of Total	98.90%	99.30%
Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	$ 13,465	$ 8,631
% of Total	1.10%	0.70%
Residential Mortgage
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	$ 701,982	$ 639,372
% of Total	100.00%	100.00%
Residential Mortgage | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	$ 692,064	$ 633,743
% of Total	98.60%	99.10%
Residential Mortgage | Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	$ 9,918	$ 5,629
% of Total	1.40%	0.90%
Home Equity
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	$ 482,284	$ 470,845
% of Total	100.00%	100.00%
Home Equity | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	$ 478,845	$ 467,943
% of Total	99.30%	99.40%
Home Equity | Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	$ 3,439	$ 2,902
% of Total	0.70%	0.60%
Installment and Other Consumer
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	$ 65,852	$ 73,939
% of Total	100.00%	100.00%
Installment and Other Consumer | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	$ 65,744	$ 73,839
% of Total	99.80%	99.80%
Installment and Other Consumer | Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	$ 108	$ 100
% of Total	0.20%	0.20%
Consumer Construction
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	$ 5,906	$ 6,579
% of Total	100.00%	100.00%
Consumer Construction | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	$ 5,906	$ 6,579
% of Total	100.00%	100.00%
Consumer Construction | Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	$ 0	$ 0
% of Total	0.00%	0.00%

Allowance for Loan Losses - Add

Allowance for Loan Losses - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Receivables [Abstract]
Minimum period interest and principal of loans past due considered nonperforming (in days)	90 days
Evaluation for impairment of substandard and nonaccrual commercial loans	$ 500,000
Impaired financing receivables	41,935,000	$ 45,650,000
Acquired loans that experienced credit deterioration since acquisition	18,400,000
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans Receivable, Net	5,615,212,000	5,062,933,000
Integrity Bancshares, Inc.
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses of acquired loans		0
Loans Receivable, Net	$ 543,300,000	$ 673,300,000

Allowance for Loan Losses - Inv

Allowance for Loan Losses - Investments in Loans Considered to be Impaired and Related Information on Impaired Loans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Impaired [Line Items]
With a related allowance recorded, Recorded Investment	$ 991	$ 618
With a related allowance recorded, Unpaid Principal Balance	2,460	1,468
With a related allowance recorded, Related Allowance	798	37
Without a related allowance recorded, Recorded Investment	40,944	45,032
Without a related allowance, Unpaid Principal Balance	48,539	50,286
Without a related allowance recorded, Related Allowance	0	0
Impaired financing receivables	41,935	45,650
Impaired Financing Receivable, Unpaid Principal Balance, Total	50,999	51,754
Impaired Financing Receivable, Related Allowance, Total	798	37
Without a related allowance recorded, Average Recorded Investment	43,334	46,638
Without a related allowance recorded, Interest Income Recognized	990	1,741
With a related allowance recorded, Average Recorded Investment	2,468	956
With a related allowance recorded, Interest Income Recognized	2	7
Impaired Financing Receivable, Average Recorded Investment, Total	45,802	47,594
Impaired Financing Receivable, Interest Income Recognized, Total	992	1,748
Commercial Real Estate
Financing Receivable, Impaired [Line Items]
With a related allowance recorded, Recorded Investment	0	0
With a related allowance recorded, Unpaid Principal Balance	0	0
With a related allowance recorded, Related Allowance	0	0
Without a related allowance recorded, Recorded Investment	16,352	12,661
Without a related allowance, Unpaid Principal Balance	17,654	13,157
Without a related allowance recorded, Related Allowance	0	0
Impaired financing receivables	16,352	12,661
Impaired Financing Receivable, Unpaid Principal Balance, Total	17,654	13,157
Impaired Financing Receivable, Related Allowance, Total	0	0
Without a related allowance recorded, Average Recorded Investment	17,496	14,622
Without a related allowance recorded, Interest Income Recognized	144	597
With a related allowance recorded, Average Recorded Investment	0	0
With a related allowance recorded, Interest Income Recognized	0	0
Impaired Financing Receivable, Average Recorded Investment, Total	17,496	14,622
Impaired Financing Receivable, Interest Income Recognized, Total	144	597
Commercial and Industrial
Financing Receivable, Impaired [Line Items]
With a related allowance recorded, Recorded Investment	964	0
With a related allowance recorded, Unpaid Principal Balance	2,433	0
With a related allowance recorded, Related Allowance	771	0
Without a related allowance recorded, Recorded Investment	5,902	14,417
Without a related allowance, Unpaid Principal Balance	7,699	15,220
Without a related allowance recorded, Related Allowance	0	0
Impaired financing receivables	6,866	14,417
Impaired Financing Receivable, Unpaid Principal Balance, Total	10,132	15,220
Impaired Financing Receivable, Related Allowance, Total	771	0
Without a related allowance recorded, Average Recorded Investment	6,141	14,416
Without a related allowance recorded, Interest Income Recognized	160	450
With a related allowance recorded, Average Recorded Investment	2,438	0
With a related allowance recorded, Interest Income Recognized	0	0
Impaired Financing Receivable, Average Recorded Investment, Total	8,579	14,416
Impaired Financing Receivable, Interest Income Recognized, Total	160	450
Commercial Construction
Financing Receivable, Impaired [Line Items]
With a related allowance recorded, Recorded Investment	0	500
With a related allowance recorded, Unpaid Principal Balance	0	1,350
With a related allowance recorded, Related Allowance	0	3
Without a related allowance recorded, Recorded Investment	6,613	10,998
Without a related allowance, Unpaid Principal Balance	10,306	14,200
Without a related allowance recorded, Related Allowance	0	0
Impaired financing receivables	6,613	11,498
Impaired Financing Receivable, Unpaid Principal Balance, Total	10,306	15,550
Impaired Financing Receivable, Related Allowance, Total	0	3
Without a related allowance recorded, Average Recorded Investment	7,723	10,581
Without a related allowance recorded, Interest Income Recognized	162	329
With a related allowance recorded, Average Recorded Investment	0	834
With a related allowance recorded, Interest Income Recognized	0	0
Impaired Financing Receivable, Average Recorded Investment, Total	7,723	11,415
Impaired Financing Receivable, Interest Income Recognized, Total	162	329
Consumer Real Estate
Financing Receivable, Impaired [Line Items]
With a related allowance recorded, Recorded Investment	26	116
With a related allowance recorded, Unpaid Principal Balance	26	116
With a related allowance recorded, Related Allowance	26	32
Without a related allowance recorded, Recorded Investment	12,053	6,845
Without a related allowance, Unpaid Principal Balance	12,849	7,521
Without a related allowance recorded, Related Allowance	0	0
Impaired financing receivables	12,079	6,961
Impaired Financing Receivable, Unpaid Principal Balance, Total	12,875	7,637
Impaired Financing Receivable, Related Allowance, Total	26	32
Without a related allowance recorded, Average Recorded Investment	11,939	6,902
Without a related allowance recorded, Interest Income Recognized	523	364
With a related allowance recorded, Average Recorded Investment	28	120
With a related allowance recorded, Interest Income Recognized	2	7
Impaired Financing Receivable, Average Recorded Investment, Total	11,967	7,022
Impaired Financing Receivable, Interest Income Recognized, Total	525	371
Other Consumer
Financing Receivable, Impaired [Line Items]
With a related allowance recorded, Recorded Investment	1	2
With a related allowance recorded, Unpaid Principal Balance	1	2
With a related allowance recorded, Related Allowance	1	2
Without a related allowance recorded, Recorded Investment	24	111
Without a related allowance, Unpaid Principal Balance	31	188
Without a related allowance recorded, Related Allowance	0	0
Impaired financing receivables	25	113
Impaired Financing Receivable, Unpaid Principal Balance, Total	32	190
Impaired Financing Receivable, Related Allowance, Total	1	2
Without a related allowance recorded, Average Recorded Investment	35	117
Without a related allowance recorded, Interest Income Recognized	1	1
With a related allowance recorded, Average Recorded Investment	2	2
With a related allowance recorded, Interest Income Recognized	0	0
Impaired Financing Receivable, Average Recorded Investment, Total	37	119
Impaired Financing Receivable, Interest Income Recognized, Total	$ 1	$ 1

Allowance for Loan Losses - Sum

Allowance for Loan Losses - Summary of Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of year				$ 48,147				$ 47,911	$ 48,147	$ 47,911
Charge-offs									(15,561)	(15,266)
Recoveries									2,224	5,114
Net (Charge-offs) Recoveries									(13,337)	(10,152)
Provision for loan losses	$ 5,586	$ 2,516	$ 4,848	5,014	$ 3,915	$ 3,206	$ 2,059	1,207	17,965	10,388	$ 1,715
Balance at End of Year	52,775				48,147				52,775	48,147	47,911
Commercial Real Estate
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of year				15,043				20,164	15,043	20,164
Charge-offs									(3,114)	(2,787)
Recoveries									692	3,545
Net (Charge-offs) Recoveries									(2,422)	758
Provision for loan losses									7,355	(5,879)
Balance at End of Year	19,976				15,043				19,976	15,043	20,164
Commercial and Industrial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of year				10,853				13,668	10,853	13,668
Charge-offs									(6,810)	(5,463)
Recoveries									722	605
Net (Charge-offs) Recoveries									(6,088)	(4,858)
Provision for loan losses									6,045	2,043
Balance at End of Year	10,810				10,853				10,810	10,853	13,668
Commercial Construction
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of year				12,625				6,093	12,625	6,093
Charge-offs									(1,877)	(3,321)
Recoveries									21	143
Net (Charge-offs) Recoveries									(1,856)	(3,178)
Provision for loan losses									3,230	9,710
Balance at End of Year	13,999				12,625				13,999	12,625	6,093
Consumer Real Estate
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of year				8,400				6,333	8,400	6,333
Charge-offs									(1,657)	(2,167)
Recoveries									433	495
Net (Charge-offs) Recoveries									(1,224)	(1,672)
Provision for loan losses									(1,081)	3,739
Balance at End of Year	6,095				8,400				6,095	8,400	6,333
Other Consumer
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of year				$ 1,226				$ 1,653	1,226	1,653
Charge-offs									(2,103)	(1,528)
Recoveries									356	326
Net (Charge-offs) Recoveries									(1,747)	(1,202)
Provision for loan losses									2,416	775
Balance at End of Year	$ 1,895				$ 1,226				$ 1,895	$ 1,226	$ 1,653

Allowance for Loan Losses - S87

Allowance for Loan Losses - Summary of Allowance for Loan Losses and Recorded Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	$ 798	$ 37
Allowance for Loan Losses, Collectively Evaluated for Impairment	51,977	48,110
Total Allowance for Loan Losses	52,775	48,147	$ 47,911
Portfolio Loans, Individually Evaluated for Impairment	41,935	45,650
Portfolio Loans, Collectively Evaluated for Impairment	5,569,484	4,981,962
Total Portfolio Loans	5,611,419	5,027,612
Commercial Real Estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	0	0
Allowance for Loan Losses, Collectively Evaluated for Impairment	19,976	15,043
Total Allowance for Loan Losses	19,976	15,043	20,164
Portfolio Loans, Individually Evaluated for Impairment	16,352	12,661
Portfolio Loans, Collectively Evaluated for Impairment	2,482,124	2,153,942
Total Portfolio Loans	2,498,476	2,166,603
Commercial and Industrial
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	771	0
Allowance for Loan Losses, Collectively Evaluated for Impairment	10,039	10,853
Total Allowance for Loan Losses	10,810	10,853	13,668
Portfolio Loans, Individually Evaluated for Impairment	6,866	14,417
Portfolio Loans, Collectively Evaluated for Impairment	1,394,169	1,242,413
Total Portfolio Loans	1,401,035	1,256,830
Commercial Construction
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	0	3
Allowance for Loan Losses, Collectively Evaluated for Impairment	13,999	12,622
Total Allowance for Loan Losses	13,999	12,625	6,093
Portfolio Loans, Individually Evaluated for Impairment	6,613	11,498
Portfolio Loans, Collectively Evaluated for Impairment	449,271	401,946
Total Portfolio Loans	455,884	413,444
Consumer Real Estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	26	32
Allowance for Loan Losses, Collectively Evaluated for Impairment	6,069	8,368
Total Allowance for Loan Losses	6,095	8,400	6,333
Portfolio Loans, Individually Evaluated for Impairment	12,079	6,961
Portfolio Loans, Collectively Evaluated for Impairment	1,178,093	1,109,835
Total Portfolio Loans	1,190,172	1,116,796
Other Consumer
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	1	2
Allowance for Loan Losses, Collectively Evaluated for Impairment	1,894	1,224
Total Allowance for Loan Losses	1,895	1,226	$ 1,653
Portfolio Loans, Individually Evaluated for Impairment	25	113
Portfolio Loans, Collectively Evaluated for Impairment	65,827	73,826
Total Portfolio Loans	$ 65,852	$ 73,939

Premises and Equipment - Summar

Premises and Equipment - Summary of Premises and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 98,714	$ 98,396
Accumulated depreciation	(53,715)	(49,269)
Premises and equipment, net	44,999	49,127
Land
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	6,397	8,699
Premises
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	52,696	52,968
Furniture and Equipment
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	32,328	29,543
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 7,293	$ 7,186

Premises and Equipment - Additi

Premises and Equipment - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 4,966	$ 4,739	$ 3,465
Lease expiration year	Jan. 1, 2054
Rental expense	$ 4,100	$ 3,900	$ 2,700
Two Directors
Property, Plant and Equipment [Line Items]
Rental expense for premises leases with two directors	$ 300

Premises and Equipment - Minimu

Premises and Equipment - Minimum Annual Rental and Renewal Option Payments (Details) $ in Thousands	Dec. 31, 2016USD ($)
Property, Plant and Equipment [Abstract]
Operating, 2017	$ 3,388
Operating, 2018	3,394
Operating, 2019	3,430
Operating, 2020	3,380
Operating, 2021	3,401
Operating, Thereafter	57,864
Operating, Total	74,857
Capital, 2017	76
Capital, 2018	76
Capital, 2019	76
Capital, 2020	77
Capital, 2021	77
Capital, Thereafter	534
Capital, Total	916
2,017	3,464
2,018	3,470
2,019	3,506
2,020	3,457
2,021	3,478
Thereafter	58,398
Total	$ 75,773

Goodwill and Other Intangible91

Goodwill and Other Intangible Assets - Roll Forward of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Goodwill [Roll Forward]
Balance at beginning of year	$ 291,764	$ 175,820
Additions	0	115,944
Other adjustments	(94)	0
Balance at End of Year	$ 291,670	$ 291,764

Goodwill and Other Intangible92

Goodwill and Other Intangible Assets - Additional Information (Details) - USD ($) $ in Thousands	10 Months Ended	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill [Line Items]
Goodwill, adjustments during measurement period		$ 94	$ 0
Goodwill acquired		0	115,944
Acquisition of core deposits	$ 4,500		4,500
Acquisition of wealth management relationships	100		100
Acquisition of insurance contract relationships	300		300
Finite-lived Intangible Assets Acquired		0	5,713
Amortization expense on finite-lived intangible assets		1,615	1,818	$ 1,129
Integrity Bancshares, Inc.
Goodwill [Line Items]
Goodwill, adjustments during measurement period	$ (1,100)	$ 100
Goodwill acquired			115,900
Finite-lived Intangible Assets Acquired			$ 5,700

Goodwill and Other Intangible93

Goodwill and Other Intangible Assets - Summary of Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Gross carrying amount at beginning of year	$ 22,114	$ 16,401
Additions	0	5,713
Accumulated amortization	(17,204)	(15,589)
Gross carrying amount at end of year	$ 4,910	$ 6,525

Goodwill and Other Intangible94

Goodwill and Other Intangible Assets - Summary of Expected Amortization Expense for Finite-Lived Intangibles Assets (Details) $ in Thousands	Dec. 31, 2016USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
2,017	$ 1,311
2,018	812
2,019	689
2,020	588
2,021	512
Total	$ 3,912

Derivative Instruments and He95

Derivative Instruments and Hedging Activities - Value of Derivative Assets and Derivative Liabilities (Details) - Not Designated as Hedging Instruments - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Derivatives not Designated as Hedging Instruments
Fair value, Derivatives (included in Other Assets)	$ 6,960	$ 11,295
Fair value, Derivatives (included in Other Liabilities)	6,958	11,276
Collateral posted, Derivatives (included in Other Liabilities)	14,340	12,573
Other Assets | Interest Rate Swap Contracts-Commercial Loans
Derivatives not Designated as Hedging Instruments
Fair value, Derivatives (included in Other Assets)	6,960	11,295
Notional amount, Derivatives (included in Other Assets)	232,396	245,595
Other Assets | Interest Rate Lock Commitments-Mortgage Loans
Derivatives not Designated as Hedging Instruments
Fair value, Derivatives (included in Other Assets)	236	261
Notional amount, Derivatives (included in Other Assets)	8,490	9,894
Other Assets | Forward Sale Contracts-Mortgage Loans
Derivatives not Designated as Hedging Instruments
Fair value, Derivatives (included in Other Assets)	0	0
Notional amount, Derivatives (included in Other Assets)	0	0
Other Liabilities | Interest Rate Swap Contracts-Commercial Loans
Derivatives not Designated as Hedging Instruments
Fair value, Derivatives (included in Other Liabilities)	6,958	11,276
Notional amount, Derivatives (included in Other Liabilities)	232,396	245,595
Collateral posted, Derivatives (included in Other Liabilities)	14,340	12,753
Other Liabilities | Forward Sale Contracts-Mortgage Loans
Derivatives not Designated as Hedging Instruments
Fair value, Derivatives (included in Other Liabilities)	27	5
Notional amount, Derivatives (included in Other Liabilities)	$ 8,216	$ 9,800

Derivative Instruments and He96

Derivative Instruments and Hedging Activities - Schedule of Gross Amounts of Derivative Assets and Derivative Liabilities (Details) - Not Designated as Hedging Instruments - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Derivatives not Designated as Hedging Instruments
Gross amounts recognized	$ 8,590	$ 11,295
Gross amounts offset	(1,630)	0
Net amounts presented in the Consolidated Balance Sheets	6,960	11,295
Net Amount	6,960	11,295
Gross amounts recognized	8,588	11,276
Gross amounts offset	(1,630)	0
Net amounts presented in the Consolidated Balance Sheets	6,958	11,276
Collateral Already Posted, Aggregate Fair Value	(14,340)	(12,573)
Net Amount	$ (7,382)	$ (1,297)

Derivative Instruments and He97

Derivative Instruments and Hedging Activities - Amount of Gain or Loss Recognized in Income on Derivatives (Details) - Not Designated as Hedging Instruments - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Total Derivative(Loss) Gain	$ (63)	$ 70	$ 36
Interest Rate Swap Contracts-Commercial Loans
Derivative Instruments, Gain (Loss) [Line Items]
Total Derivative(Loss) Gain	(16)	(8)	(24)
Interest Rate Lock Commitments-Mortgage Loans
Derivative Instruments, Gain (Loss) [Line Items]
Total Derivative(Loss) Gain	(25)	26	150
Forward Sale Contracts-Mortgage Loans
Derivative Instruments, Gain (Loss) [Line Items]
Total Derivative(Loss) Gain	$ (22)	$ 52	$ (90)

Mortgage Servicing Rights - Add

Mortgage Servicing Rights - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Mortgage Loan Activity [Line Items]
Sale of 1-4 family mortgage loans	$ 108,209	$ 99,458	$ 42,361
Total servicing portfolio	407,300	361,200	325,800
Fannie Mae
Mortgage Loan Activity [Line Items]
Sale of 1-4 family mortgage loans	$ 93,900	$ 76,800	$ 40,100

Mortgage Servicing Rights - Sch

Mortgage Servicing Rights - Schedule of Mortgage Servicing Rights and Net Carrying Values (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Servicing Rights
Beginning Balance	$ 3,426	$ 3,108
Additions	1,047	856
Amortization	(615)	(538)
Ending Balance	3,858	3,426
Valuation Allowance
Beginning Balance	(189)	(291)
Temporary (impairment) recapture	75	102
Ending Balance	(114)	(189)
Net Carrying Value
Beginning balance	3,237	2,817
Additions	1,047	856
Amortization	(615)	(538)
Temporary (impairment) recapture	75	102
Ending balance	$ 3,744	$ 3,237

Qualified Affordable Housing (D

Qualified Affordable Housing (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Equity Method Investments [Line Items]
Investments in qualified affordable housing projects	$ 11,700,000	$ 15,000,000
Open commitments to fund future investments qualifiedd affordable housing projects	0	0
Tax credits to offset amortization expense of investments in affordable housing projects	3,700,000	4,000,000	$ 4,300,000
Noninterest Expense
Schedule of Equity Method Investments [Line Items]
Amortization expense of investments in qualified affordable housing projects	$ 3,300,000	$ 3,600,000	$ 4,100,000

Deposits - Composition of Depos

Deposits - Composition of Deposits and Interest Expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule Of Deposits And Borrowings Maturities [Line Items]
Balance	$ 5,272,377	$ 4,876,611	$ 3,908,842
Interest Expense	19,692	12,944	10,128
Noninterest-bearing demand
Schedule Of Deposits And Borrowings Maturities [Line Items]
Balance	1,263,833	1,227,766	1,083,919
Interest-bearing demand
Schedule Of Deposits And Borrowings Maturities [Line Items]
Balance	638,300	616,188	335,099
Interest Expense	111	818	19
Money market
Schedule Of Deposits And Borrowings Maturities [Line Items]
Balance	936,461	605,184	376,612
Interest Expense	4,199	1,299	572
Savings
Schedule Of Deposits And Borrowings Maturities [Line Items]
Balance	1,050,131	1,061,265	1,027,095
Interest Expense	2,002	1,712	1,607
Certificates of deposit
Schedule Of Deposits And Borrowings Maturities [Line Items]
Balance	1,383,652	1,366,208	1,086,117
Interest Expense	$ 13,380	$ 9,115	$ 7,930

Deposits - Additional Informati

Deposits - Additional Information (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Banking and Thrift [Abstract]
Aggregate value of certificate of deposit over $100,000	$ 671.5	$ 555.4

Deposits - Scheduled Maturities

Deposits - Scheduled Maturities of Certificates of Deposit (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Banking and Thrift [Abstract]
2,017	$ 1,017,744
2,018	221,829
2,019	48,890
2,020	38,629
2,021	48,438
Thereafter	8,122
Total	$ 1,383,652	$ 1,366,208

- Composition of Short-Term Bor

- Composition of Short-Term Borrowings, Interest Expense and Weighted Average Interest Rate (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Short-term Debt [Line Items]
Securities available-for-sale, amortized cost	$ 686,205	$ 650,782
Securities available-for-sale, at fair value	693,487	660,963
Balance	$ 710,832	$ 418,086	$ 320,605
Weighted Average Interest Rate	0.70%	0.44%	0.27%
Interest Expense	$ 2,718	$ 936	$ 514
REPOs
Short-term Debt [Line Items]
Balance	$ 50,832	$ 62,086	$ 30,605
Weighted Average Interest Rate	0.01%	0.01%	0.01%
Interest Expense	$ 5	$ 4	$ 3
FHLB advances
Short-term Debt [Line Items]
Balance	$ 660,000	$ 356,000	$ 290,000
Weighted Average Interest Rate	0.76%	0.52%	0.31%
Interest Expense	$ 2,713	$ 932	$ 511
Securities Pledged as Collateral
Short-term Debt [Line Items]
Securities available-for-sale, amortized cost	53,100	67,000
Securities available-for-sale, at fair value	$ 52,900	$ 66,900

Long-Term Borrowings and Sub105

Long-Term Borrowings and Subordinated Debt - Additional Information (Details) - USD ($)	Jun. 18, 2015	Mar. 05, 2015	Dec. 31, 2016	Dec. 31, 2015	Mar. 04, 2015
Debt Instrument [Line Items]
Long-term borrowings			$ 14,700,000	$ 117,000,000
Total loans pledged as collateral			3,200,000,000
Maximum eligible borrowing based on qualifying collateral			1,400,000,000
Maximum borrowing capacity			2,300,000,000
Capital lease			$ 100,000
Percentage of equity owned			100.00%
2006 Junior Subordinated Debt | Integrity Bancshares, Inc.
Debt Instrument [Line Items]
Junior subordinated debt assumed on acquisition					$ 13,500,000
Junior subordinated debt paid off	$ 5,000,000	$ 8,500,000

Long-Term Borrowings and Sub106

Long-Term Borrowings and Subordinated Debt - Schedule of Long-Term Borrowings, Interest Expense and Weighted Average Interest Rate (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Debt Disclosure [Abstract]
Long-term borrowings	$ 14,713	$ 117,043	$ 19,442
Weighted average interest rate	2.91%	0.81%	3.00%
Interest expense	$ 670	$ 790	$ 617

Long-Term Borrowings and Sub107

Long-Term Borrowings and Subordinated Debt - Schedule of Annual Maturities and Average Interest Rate of Long-Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Debt Disclosure [Abstract]
2017 Balance	$ 2,412
2018 Balance	2,496
2019 Balance	2,514
2020 Balance	2,004
2021 Balance	1,057
Thereafter Balance	4,230
Total Long-term Balance	$ 14,713	$ 117,043	$ 19,442
2017 Average Rate	3.52%
2018 Average Rate	3.60%
2019 Average Rate	3.13%
2020 Average Rate	3.22%
2021 Average Rate	3.44%
Thereafter Average Rate	1.84%
Total Average Rate	2.94%

Long-Term Borrowings and Sub108

Long-Term Borrowings and Subordinated Debt - Schedule of Junior Subordinated Debt Securities and Interest Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Junior Subordinated Debentures [Line Items]
Balance	$ 45,619	$ 45,619	$ 45,619
Interest Expense	1,434	1,327	1,222
2006 Junior Subordinated Debt
Junior Subordinated Debentures [Line Items]
Balance	25,000	25,000	25,000
Interest Expense	580	554	463
2008 Junior subordinated debt—trust preferred securities
Junior Subordinated Debentures [Line Items]
Balance	20,619	20,619	20,619
Interest Expense	$ 854	$ 773	$ 759

Long-Term Borrowings and Sub109

Long-Term Borrowings and Subordinated Debt - Schedule of Junior Subordinated Debt Securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Junior Subordinated Debentures [Line Items]
Junior subordinated debt securities	$ 45,619	$ 45,619	$ 45,619
Interest Rate at December 31, 2016	2.91%	0.81%	3.00%
2006 Junior Subordinated Debt
Junior Subordinated Debentures [Line Items]
Junior subordinated debt securities	$ 25,000	$ 25,000	$ 25,000
Stated Maturity Date	Dec. 15, 2036
Optional redemption date at par	Any time after 9/15/2011
Regulatory Capital	Tier 2
Interest Rate at December 31, 2016	2.56%
2006 Junior Subordinated Debt | 3-Month LIBOR
Junior Subordinated Debentures [Line Items]
Basis spread on base interest rate	160.00%
2008 Trust Preferred Securities
Junior Subordinated Debentures [Line Items]
Junior subordinated debt securities	$ 20,619	$ 20,619	$ 20,619
Trust Preferred Securities	$ 20,619
Stated Maturity Date	Mar. 15, 2038
Optional redemption date at par	Any time after 3/15/2013
Regulatory Capital	Tier 1
Interest Rate at December 31, 2016	4.46%
2008 Trust Preferred Securities | 3-Month LIBOR
Junior Subordinated Debentures [Line Items]
Basis spread on base interest rate	350.00%

Commitments and Contingencies -

Commitments and Contingencies - Commitments and Letters of Credit (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Commitment And Contingencies [Line Items]
Commitments and letters of credit	$ 1,594,230	$ 1,717,530
Standby Letters of Credit
Commitment And Contingencies [Line Items]
Commitments and letters of credit	84,534	97,676
Commitments to Extend Credit
Commitment And Contingencies [Line Items]
Commitments and letters of credit	$ 1,509,696	$ 1,619,854

Commitments and Contingencie111

Commitments and Contingencies - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Allowance for unfunded commitments	$ 2,600,000	$ 2,500,000
Data processing and communication charges	10,400,000	11,700,000	$ 9,800,000
Data processing, contract termination and conversion cost expenses	$ 0	$ 1,300,000	$ 0

- Future Estimated Payments Rel

- Future Estimated Payments Related to Data Processing and Communication Charges (Details) $ in Thousands	Dec. 31, 2016USD ($)
Commitments and Contingencies Disclosure [Abstract]
2,017	$ 11,671
2,018	12,046
2,019	12,451
2,020	12,875
2,021	13,315
Total	$ 62,358

Income Taxes - Schedule of Inco

Income Taxes - Schedule of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Federal
Current									$ 24,521	$ 24,825	$ 15,979
Deferred									665	(427)	1,536
Total Federal									25,186	24,398	17,515
State
Current									248	0	0
Deferred									(129)	0	0
Total Federal and State									119	0	0
Total State	$ 6,510	$ 7,367	$ 5,496	$ 5,931	$ 6,814	$ 6,407	$ 6,498	$ 4,680	$ 25,305	$ 24,398	$ 17,515

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule Of Income Taxes [Line Items]
Statutory tax rate	35.00%	35.00%	35.00%
Valuation allowance related to gross deferred tax assets	$ 3,114	$ 2,670
Deferred tax assets operating loss carry forwards, total	31,200
Unrecognized tax benefits, accrued interest	$ 100	$ 100	$ 100
Minimum
Schedule Of Income Taxes [Line Items]
Deferred tax assets operating loss carry forwards, expiration date	2,020
Maximum
Schedule Of Income Taxes [Line Items]
Deferred tax assets operating loss carry forwards, expiration date	2,036
PENNSYLVANIA
Schedule Of Income Taxes [Line Items]
Valuation allowance related to gross deferred tax assets	$ 3,100

Income Taxes - Schedule of Stat

Income Taxes - Schedule of Statutory to Effective Tax Rate Reconciliation (Details)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Statutory tax rate	35.00%	35.00%	35.00%
Low income housing tax credits	(3.80%)	(4.40%)	(5.80%)
Tax-exempt interest	(4.40%)	(4.10%)	(4.60%)
Bank owned life insurance	(0.80%)	(0.80%)	(0.80%)
Other	0.20%	1.00%	(0.60%)
Effective Tax Rate	26.20%	26.70%	23.20%

Income Taxes - Significant Comp

Income Taxes - Significant Components of Temporary Differences with Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred Tax Liabilities:
Net unrealized holding gains on securities available-for-sale	$ (2,557)	$ (3,563)
Prepaid pension	(2,770)	(2,865)
Deferred loan income	(3,815)	(2,847)
Depreciation on premises and equipment	(1,239)	(1,226)
Other	(1,766)	(809)
Total Deferred Tax liabilities	(12,147)	(11,310)
Deferred Tax Assets:
Allowance for loan losses	19,446	17,740
Purchase accounting adjustments	365	1,298
Other employee benefits	3,983	2,556
Low income housing partnerships	4,845	4,531
Net adjustment to funded status of pension	10,018	12,425
Impairment of securities	1,318	1,354
State net operating loss carryforwards	3,114	2,670
Other	4,984	6,155
Gross Deferred Tax Assets	48,073	48,729
Less: Valuation allowance	(3,114)	(2,670)
Total Deferred Tax Assets	44,959	46,059
Net Deferred Tax Asset	$ 32,812	$ 34,749

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Change in Federal and State Gross Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at beginning of year	$ 1,102	$ 284	$ 1,902
Increase	0	818	55
Decrease	(449)	0	(1,673)
Current period tax positions	151	0	0
Reductions for statute of limitations expirations	0	0	0
Balance at End of Year	804	1,102	284
Amount That Would Affect the Effective Tax Rate if Recognized	$ 610	$ 542	$ 184

Tax Effects on Other Compreh118

Tax Effects on Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accumulated Net Investment Gain (Loss) Attributable to Parent
Pre-Tax Amount
Net change in unrealized gains on securities available-for-sale	$ (2,899)	$ (663)	$ 11,825
Net available-for-sale securities losses (gains) reclassified into earnings	0	(34)	41
Tax (Expense) Benefit
Net change in unrealized gains on securities available-for-sale	1,006	232	(4,139)
Net available-for-sale securities losses (gains) reclassified into earnings	0	(12)	15
Net of Tax Amount
Net change in unrealized gains on securities available-for-sale	(1,893)	(431)	7,686
Net available-for-sale securities losses (gains) reclassified into earnings	0	22	(26)
Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent
Pre-Tax Amount
Other Comprehensive Income (Loss), before Tax	6,974	(3,551)	(13,394)
Tax (Expense) Benefit
Other Comprehensive Income (Loss), Tax	(2,408)	1,336	4,595
Net of Tax Amount
Other Comprehensive Income (Loss), Net of Tax	4,566	(2,215)	(8,799)
Accumulated Other Comprehensive Income (Loss)
Pre-Tax Amount
Other Comprehensive Income (Loss), before Tax	(4,075)	4,180	1,610
Tax (Expense) Benefit
Other Comprehensive Income (Loss), Tax	1,402	(1,556)	(471)
Net of Tax Amount
Other Comprehensive Income (Loss), Net of Tax	$ (2,673)	$ 2,624	$ 1,139

Employee Benefits - Additional

Employee Benefits - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Number of consecutive years of employee's compensation	5 years
Number of total years of employee's compensation	10 years
Accumulated benefit obligation	$ 105,800,000	$ 101,600,000
Pension contributions	0
Projected benefit obligation	105,834,000	109,747,000	$ 113,124,000
Net periodic benefit cost	296,000	1,736,000	736,000
Level 1 to Level 2 transfers	0
Purchases, transfers or sales of level 3 plan assets	0
Scenario, Forecast
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss included in accumulated other comprehensive losses expected to be recognized				$ (1,900,000)
Supplemental Executive Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	4,700,000	4,000,000
Net periodic benefit cost	500,000	600,000	400,000
Defined benefit plan in accumulated other comprehensive gain/loss before tax	$ 2,500,000	2,100,000
Thrift Plan
Defined Benefit Plan Disclosure [Line Items]
Contributions to the Thrift Plan	3.50%
Compensation expense	$ 1,700,000	$ 1,500,000	$ 1,300,000
Marketable equity securities
Defined Benefit Plan Disclosure [Line Items]
Targeted asset allocation minimum	50.00%
Targeted asset allocation maximum	70.00%
Fixed Income
Defined Benefit Plan Disclosure [Line Items]
Targeted asset allocation minimum	30.00%
Targeted asset allocation maximum	50.00%

Employee Benefits - Benefit Obl

Employee Benefits - Benefit Obligation and Plan Assets Deriving Funded Status, in Other Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Change in Projected Benefit Obligation
Projected benefit obligation at beginning of year	$ 109,747	$ 113,124
Service cost	463	2,601	$ 2,369
Interest cost	4,296	4,425	4,470
Actuarial loss (gain)	3,575	(4,257)
Curtailments	(6,997)	0
Benefits paid	(5,250)	(6,146)
Projected Benefit Obligation at End of Year	105,834	109,747	113,124
Change in Plan Assets
Fair value of plan assets at beginning of year	84,585	93,486
Actual return on plan assets	8,376	(2,755)
Benefits paid	(5,250)	(6,146)
Fair Value of Plan Assets at End of Year	87,711	84,585	$ 93,486
Funded Status	$ (18,123)	$ (25,162)

Employee Benefits - Accumulated

Employee Benefits - Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Compensation and Retirement Disclosure [Abstract]
Prior service credit	$ 0	$ (1,029)
Net actuarial loss	26,013	34,376
Total (Before Tax Effects)	$ 26,013	$ 33,347

Employee Benefits - Actuarial W

Employee Benefits - Actuarial Weighted Average Assumptions Used in Determining Benefit Obligation (Details)	Dec. 31, 2016	Dec. 31, 2015
Compensation and Retirement Disclosure [Abstract]
Discount rate	4.00%	4.25%
Rate of compensation increase	0.00%	3.00%

Employee Benefits - Components

Employee Benefits - Components of Net Periodic Pension Cost and Other Changes in Plan Assets and Benefit Obligation Recognized in Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Components of Net Periodic Pension Cost
Service cost—benefits earned during the period	$ 463	$ 2,601	$ 2,369
Interest cost on projected benefit obligation	4,296	4,425	4,470
Expected return on plan assets	(5,780)	(7,180)	(6,907)
Amortization of prior service credit	(11)	(138)	(137)
Recognized net actuarial loss	2,345	2,028	941
Curtailment (gain)	(1,017)	0	0
Net Periodic Pension Expense	296	1,736	736
Other Changes in Plan Assets and Benefit Obligation Recognized in Other Comprehensive Income (Loss)
Net actuarial (gain) loss	(6,018)	5,678	13,294
Recognized net actuarial loss	(2,345)	(2,028)	(941)
Recognized prior service credit	1,029	138	137
Total (Before Tax Effects)	(7,334)	3,788	12,490
Total Recognized in Net Benefit Cost and Other Comprehensive (Loss)/Income (Before Tax Effects)	$ (7,038)	$ 5,524	$ 13,226

- Actuarial Weighted Average As

- Actuarial Weighted Average Assumptions Used in Determining Net Periodic Pension Cost (Details)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Compensation and Retirement Disclosure [Abstract]
Discount rate	4.25%	4.00%	4.75%
Rate of compensation increase	3.00%	3.00%	3.00%
Expected return on assets	7.50%	8.00%	8.00%

Employee Benefits - Estimated F

Employee Benefits - Estimated Future Benefit Payments (Details) $ in Thousands	Dec. 31, 2016USD ($)
Compensation and Retirement Disclosure [Abstract]
2,017	$ 6,788
2,018	6,855
2,019	6,833
2,020	6,748
2,021	6,847
2022-2026	$ 32,361

Employee Benefits - Pension Pla

Employee Benefits - Pension Plan Assets Measured at Fair Value on Recurring Basis (Details) - Fair Value Measurements, Recurring - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets measured at fair value	$ 87,613	$ 84,585
Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets measured at fair value	3,336	3,371
Fixed Income
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets measured at fair value	27,279	27,054
Equity Index Mutual Funds-International
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets measured at fair value	3,362	3,421
Domestic Individual Equities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets measured at fair value	53,636	50,739
Level 1
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets measured at fair value	84,277	81,214
Level 1 | Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets measured at fair value	0	0
Level 1 | Fixed Income
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets measured at fair value	27,279	27,054
Level 1 | Equity Index Mutual Funds-International
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets measured at fair value	3,362	3,421
Level 1 | Domestic Individual Equities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets measured at fair value	53,636	50,739
Level 2
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets measured at fair value	3,336	3,371
Level 2 | Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets measured at fair value	3,336	3,371
Level 2 | Fixed Income
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets measured at fair value	0	0
Level 2 | Equity Index Mutual Funds-International
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets measured at fair value	0	0
Level 2 | Domestic Individual Equities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets measured at fair value	0	0
Level 3
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets measured at fair value	0	0
Level 3 | Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets measured at fair value	0	0
Level 3 | Fixed Income
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets measured at fair value	0	0
Level 3 | Equity Index Mutual Funds-International
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets measured at fair value	0	0
Level 3 | Domestic Individual Equities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets measured at fair value	$ 0	$ 0

Incentive and Restricted Sto127

Incentive and Restricted Stock Plan and Dividend Reinvestment Plan - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of awards outstanding (in shares)	0	0	155,500	428,900
Nonstatutory stock options granted since 2006 (in shares)	0	0	0
Aggregate intrinsic value of options outstanding			$ 0
Aggregate intrinsic value of options exercisable			0
Unrecognized compensation expense to be recognized	$ 2,500,000
Weighted average compensation expense recognize period	1 year 6 months 30 days
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 2,500,000	$ 1,700,000	900,000
Tax benefit realized on compensation expense	$ 900,000	$ 600,000	$ 300,000
2014 Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of common stock authorized (in shares)	750,000
Stock plan expiration period	10 years
Number of awards outstanding (in shares)	0
2014 Stock Plan | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares granted	110,643	87,841
2014 Stock Plan | Restricted Stock | Employees and Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares granted	278,939
2014 Stock Plan | Restricted Stock | Outside Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year
Restricted shares granted	15,613	16,142	13,824
LTIP | Time-based and Performance-based Restricted Stocks | Senior Management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares granted	95,030	71,699	66,631
LTIP | Time-based Restricted Shares | Senior Management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock Award vesting after year two, percent	50.00%
Restricted Stock Award vesting after year three, percent	50.00%
LTIP | Performance-based Restricted Shares | Senior Management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years

Incentive and Restricted Sto128

Incentive and Restricted Stock Plan and Dividend Reinvestment Plan - Nonstatutory Stock Options Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Nonstatutory Stock Option Activity (shares) [Roll Forward]
Outstanding, beginning of year (in shares)	0	155,500	428,900
Granted (in shares)	0	0	0
Exercised (in shares)	0	0	0
Forfeited (in shares)	0	0	(273,400)
Expired (in shares)	0	(155,500)	0
Outstanding, End of year (in shares)	0	0	155,500
Exercisable at End of Year (in shares)	0	0	155,500
Nonstatutory Stock Options, Outstanding, Weighted Average Exercise Price (dollars per share) [Abstract]
Outstanding at beginning of year (in dollars per share)	$ 0	$ 37.86	$ 37.36
Granted (in dollars per share)	0	0	0
Exercised (in dollars per share)	0	0	0
Forfeited (in dollars per share)	0	0	37.08
Expired (in dollars per share)	0	37.86	0
Outstanding and End of Year (in dollars per share)	0	0	37.86
Exercisable at End of Year (in dollars per share)	$ 0	$ 0	$ 37.86
Outstanding at End of Year (in years)	0 years	0 years	1 year
Exercisable at End of Year (in years)	0 years	0 years	1 year

Incentive and Restricted Sto129

Incentive and Restricted Stock Plan and Dividend Reinvestment Plan - Non-vested Restricted Stock Granted (Details) - 2014 Stock Plan - Restricted Stock - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Restricted Stock
Non-vested at the beginning of the year (in shares)	150,356	79,824
Granted (in shares)	110,643	87,841
Vested (in shares)	32,164	14,126
Forfeited (in shares)	3,335	3,183
Non-vested at the end of the year (in shares)	225,500	150,356	79,824
Weighted Average Grant Date Fair Value
Non-vested at the beginning of the year (in dollars per share)	$ 26.16	$ 26.34	$ 23.24
Granted (in dollars per share)	25.58	28.71
Vested (in dollars per share)	25.03	23.57
Forfeited (in dollars per share)	26.04	26.15
Non-vested at the end of the year (in dollars per share)	$ 26.16	$ 26.34	$ 23.24

Parent Company Condensed Fin130

Parent Company Condensed Financial Information - Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Condensed Financial Information [Line Items]
Cash	$ 139,486	$ 99,399	$ 109,580	$ 108,356
Other assets	102,166	102,583
Total Assets	6,943,053	6,318,354
Other liabilities	57,556	68,758
Total Liabilities	6,101,097	5,526,117
Total Shareholders' Equity	841,956	792,237	608,389	571,306
Total Liabilities and Shareholders’ Equity	6,943,053	6,318,354
Parent Company
Condensed Financial Information [Line Items]
Cash	17,057	12,595	$ 38,028	$ 14,852
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	819,531	777,795
Nonbank subsidiaries	21,980	20,624
Other assets	4,694	2,530
Total Assets	863,262	813,544
Long-term debt	20,619	20,619
Other liabilities	687	688
Total Liabilities	21,306	21,307
Total Shareholders' Equity	841,956	792,237
Total Liabilities and Shareholders’ Equity	$ 863,262	$ 813,544

Parent Company Condensed Fin131

Parent Company Condensed Financial Information - Statements of Net Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Condensed Financial Information [Line Items]
Interest expense on long-term debt	$ 670	$ 790	$ 617
Net Income	71,392	67,081	57,910
Parent Company
Condensed Financial Information [Line Items]
Dividends from subsidiaries	34,134	75,413	46,414
Investment income	17	19	19
Interest expense on long-term debt	854	773	759
Other expenses	2,315	2,138	2,014
Income before Equity in Undistributed Net Income of Subsidiaries	30,982	72,521	43,660
Bank subsidiary	40,051	(5,064)	13,351
Nonbank subsidiaries	359	(376)	899
Net Income	$ 71,392	$ 67,081	$ 57,910

Parent Company Condensed Fin132

Parent Company Condensed Financial Information - Statements of Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Condensed Financial Information [Line Items]
Net Income	$ 71,392	$ 67,081	$ 57,910
Tax benefit from stock-based compensation	(9)	(53)	(16)
Net Cash Provided by Operating Activities	96,796	60,584	78,103
Net Cash Used in Investing Activities	(616,653)	(405,737)	(437,048)
(Purchase) Sale of treasury shares, net	(115)	(182)	(163)
Cash dividends paid to common shareholders	(26,784)	(24,487)	(20,203)
Tax benefit from stock-based compensation	9	53	16
Net Cash Provided by (Used in) Financing Activities	559,944	334,972	360,169
Net increase (decrease) in cash	40,087	(10,181)	1,224
Cash and cash equivalents at beginning of year	99,399	109,580	108,356
Cash and Cash Equivalents at End of Year	139,486	99,399	109,580
Parent Company
Condensed Financial Information [Line Items]
Net Income	71,392	67,081	57,910
Equity in undistributed (earnings) losses of subsidiaries	(40,410)	5,440	(14,250)
Tax benefit from stock-based compensation	(9)	(53)	(16)
Other	379	3,059	(106)
Net Cash Provided by Operating Activities	31,352	75,527	43,538
Net investments in subsidiaries	0	(38,404)	0
Acquisitions	0	(29,510)	0
Net Cash Used in Investing Activities	0	(67,914)	0
Repayment of junior subordinated debt	0	(8,500)	0
(Purchase) Sale of treasury shares, net	(115)	(112)	(163)
Cash dividends paid to common shareholders	(26,784)	(24,487)	(20,215)
Tax benefit from stock-based compensation	9	53	16
Net Cash Provided by (Used in) Financing Activities	(26,890)	(33,046)	(20,362)
Net increase (decrease) in cash	4,462	(25,433)	23,176
Cash and cash equivalents at beginning of year	12,595	38,028	14,852
Cash and Cash Equivalents at End of Year	$ 17,057	$ 12,595	$ 38,028

Regulatory Matters - Additional

Regulatory Matters - Additional Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)
Banking and Thrift [Abstract]
Total trust preferred securities	$ 20
Junior subordinated debt, included in Tier 2 capital	$ 25

Regulatory Matters - Summary of

Regulatory Matters - Summary of Risk-Based Capital Amounts and Ratios for S&T and S&T Bank (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
S&T
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Leverage Ratio, Actual Amount	$ 582,155	$ 535,234
Leverage Ratio, Actual Ratio	8.98%	8.96%
Leverage Ratio, Minimum Regulatory Capital Requirements Amount	$ 259,170	$ 238,841
Leverage Ratio, Minimum Regulatory Capital Requirements Ratio	4.00%	4.00%
Leverage Ratio, To be Well Capitalized Amount	$ 323,963	$ 298,551
Leverage Ratio, To be Well Capitalized Ratio	5.00%	5.00%
Tier One Common Equity Capital	$ 562,155	$ 515,234
Tier One Common Equity Capital to Risk Weighted Assets	10.04%	9.77%
Tier One Common Equity Capital Required for Capital Adequacy	$ 252,079	$ 237,315
Tier One Common Equity Capital Required for Capital Adequacy to Risk Weighted Assets	4.50%	4.50%
Tier One Common Equity Capital Required to be Well Capitalized	$ 364,114	$ 342,788
Tier One Common Equity Capital Required to be Well Capitalized to Risk Weighted Assets	6.50%	6.50%
Tier 1 Capital (to Risk-Weighted Assets), Actual Amount	$ 582,155	$ 535,234
Tier 1 Capital (to Risk-Weighted Assets), Actual Ratio	10.39%	10.15%
Tier 1 Capital (to Risk-Weighted Assets), Minimum Regulatory Capital Requirements Amount	$ 336,105	$ 316,419
Tier 1 Capital (to Risk-Weighted Assets), Minimum Regulatory Capital Requirements Ratio	6.00%	6.00%
Tier 1 Capital (to Risk-Weighted Assets), To be Well Capitalized Amount	$ 448,140	$ 421,892
Tier 1 Capital (to Risk-Weighted Assets), To be Well Capitalized Ratio	8.00%	8.00%
Total Capital (to Risk-Weighted Assets), Actual Amount	$ 664,184	$ 611,859
Total Capital (to Risk-Weighted Assets), Actual Ratio	11.86%	11.60%
Total Capital (to Risk-Weighted Assets), Minimum Regulatory Capital Requirements Amount	$ 448,140	$ 421,892
Total Capital (to Risk-Weighted Assets), Minimum Regulatory Capital Requirements Ratio	8.00%	8.00%
Total Capital (to Risk-Weighted Assets), To be Well Capitalized Amount	$ 560,175	$ 527,366
Total Capital (to Risk-Weighted Assets), To be Well Capitalized Ratio	10.00%	10.00%
S&T Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Leverage Ratio, Actual Amount	$ 542,048	$ 502,114
Leverage Ratio, Actual Ratio	8.39%	8.43%
Leverage Ratio, Minimum Regulatory Capital Requirements Amount	$ 258,460	$ 238,121
Leverage Ratio, Minimum Regulatory Capital Requirements Ratio	4.00%	4.00%
Leverage Ratio, To be Well Capitalized Amount	$ 323,075	$ 297,651
Leverage Ratio, To be Well Capitalized Ratio	5.00%	5.00%
Tier One Common Equity Capital	$ 542,048	$ 502,114
Tier One Common Equity Capital to Risk Weighted Assets	9.71%	9.55%
Tier One Common Equity Capital Required for Capital Adequacy	$ 251,213	$ 236,482
Tier One Common Equity Capital Required for Capital Adequacy to Risk Weighted Assets	4.50%	4.50%
Tier One Common Equity Capital Required to be Well Capitalized	$ 362,864	$ 341,584
Tier One Common Equity Capital Required to be Well Capitalized to Risk Weighted Assets	6.50%	6.50%
Tier 1 Capital (to Risk-Weighted Assets), Actual Amount	$ 542,048	$ 502,114
Tier 1 Capital (to Risk-Weighted Assets), Actual Ratio	9.71%	9.55%
Tier 1 Capital (to Risk-Weighted Assets), Minimum Regulatory Capital Requirements Amount	$ 334,951	$ 315,309
Tier 1 Capital (to Risk-Weighted Assets), Minimum Regulatory Capital Requirements Ratio	6.00%	6.00%
Tier 1 Capital (to Risk-Weighted Assets), To be Well Capitalized Amount	$ 446,601	$ 420,412
Tier 1 Capital (to Risk-Weighted Assets), To be Well Capitalized Ratio	8.00%	8.00%
Total Capital (to Risk-Weighted Assets), Actual Amount	$ 622,469	$ 577,824
Total Capital (to Risk-Weighted Assets), Actual Ratio	11.15%	11.00%
Total Capital (to Risk-Weighted Assets), Minimum Regulatory Capital Requirements Amount	$ 446,602	$ 420,412
Total Capital (to Risk-Weighted Assets), Minimum Regulatory Capital Requirements Ratio	8.00%	8.00%
Total Capital (to Risk-Weighted Assets), To be Well Capitalized Amount	$ 558,252	$ 525,515
Total Capital (to Risk-Weighted Assets), To be Well Capitalized Ratio	10.00%	10.00%

Segments - Additional Informati

Segments - Additional Information (Details)	12 Months Ended
	Dec. 31, 2016segment
Segment Reporting [Abstract]
Number of reportable segments	3

Segments - Total Assets by Repo

Segments - Total Assets by Reportable Operating Segment (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	$ 6,943,053	$ 6,318,354
Community Banking
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	6,930,712	6,305,046
Insurance
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	9,226	9,619
Wealth Management
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	$ 3,115	$ 3,689

Segments - Financial Informatio

Segments - Financial Information of Segments (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting, Asset Reconciling Item [Line Items]
Interest income	$ 59,096	$ 57,808	$ 55,850	$ 55,019	$ 53,353	$ 53,669	$ 52,611	$ 43,916	$ 227,774	$ 203,548	$ 160,523
Interest expense	6,638	6,353	6,142	5,382	4,468	4,073	3,800	3,657	24,515	15,997	12,481
NET INTEREST INCOME									203,259	187,551	148,042
Provision for loan losses	5,586	2,516	4,848	5,014	3,915	3,206	2,059	1,207	17,965	10,388	1,715
Noninterest income	12,922	13,448	12,448	15,817	13,084	12,481	13,417	12,084	54,635	51,033	46,338
Noninterest expense									136,651	130,160	112,646
Depreciation expense									4,966	4,739	3,465
Amortization of intangible assets									1,615	1,818	1,129
Provision (benefit) for income taxes	$ 6,510	$ 7,367	$ 5,496	$ 5,931	$ 6,814	$ 6,407	$ 6,498	$ 4,680	25,305	24,398	17,515
Net Income									71,392	67,081	57,910
Operating Segments | Community Banking
Segment Reporting, Asset Reconciling Item [Line Items]
Interest income									227,756	203,439	160,403
Interest expense									24,851	16,678	13,989
NET INTEREST INCOME									202,905	186,761	146,414
Provision for loan losses									17,965	10,388	1,715
Noninterest income									37,717	34,106	29,443
Noninterest expense									120,744	115,998	97,733
Depreciation expense									4,905	4,664	3,387
Amortization of intangible assets									1,543	1,738	1,039
Provision (benefit) for income taxes									24,872	23,209	16,311
Net Income									70,593	64,870	55,672
Operating Segments | Insurance
Segment Reporting, Asset Reconciling Item [Line Items]
Interest income									2	2	2
Interest expense									0	0	0
NET INTEREST INCOME									2	2	2
Provision for loan losses									0	0	0
Noninterest income									4,794	5,035	5,279
Noninterest expense									4,582	4,365	4,313
Depreciation expense									45	50	51
Amortization of intangible assets									50	50	51
Provision (benefit) for income taxes									42	200	303
Net Income									77	372	563
Operating Segments | Wealth Management
Segment Reporting, Asset Reconciling Item [Line Items]
Interest income									459	508	518
Interest expense									0	0	0
NET INTEREST INCOME									459	508	518
Provision for loan losses									0	0	0
Noninterest income									10,443	11,412	11,297
Noninterest expense									9,751	9,037	9,173
Depreciation expense									16	25	27
Amortization of intangible assets									22	30	39
Provision (benefit) for income taxes									391	989	901
Net Income									722	1,839	1,675
Eliminations
Segment Reporting, Asset Reconciling Item [Line Items]
Interest income									(443)	(401)	(400)
Interest expense									(336)	(681)	(1,508)
NET INTEREST INCOME									(107)	280	1,108
Provision for loan losses									0	0	0
Noninterest income									1,681	480	319
Noninterest expense									1,574	760	1,427
Depreciation expense									0	0	0
Amortization of intangible assets									0	0	0
Provision (benefit) for income taxes									0	0	0
Net Income									$ 0	$ 0	$ 0

Selected Financial Data - Summa

Selected Financial Data - Summary of Selected Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Interest income	$ 59,096	$ 57,808	$ 55,850	$ 55,019	$ 53,353	$ 53,669	$ 52,611	$ 43,916	$ 227,774	$ 203,548	$ 160,523
Interest expense	6,638	6,353	6,142	5,382	4,468	4,073	3,800	3,657	24,515	15,997	12,481
Provision for loan losses	5,586	2,516	4,848	5,014	3,915	3,206	2,059	1,207	17,965	10,388	1,715
Net Interest Income After Provision for Loan Losses	46,872	48,939	44,860	44,623	44,970	46,390	46,752	39,052	185,294	177,163	146,327
Security gains, net	0	0	0	0	0	0	(34)	0
Noninterest income	12,922	13,448	12,448	15,817	13,084	12,481	13,417	12,084	54,635	51,033	46,338
Noninterest expense	35,625	34,439	34,753	38,416	33,817	33,829	35,449	33,621	143,232	136,717	117,240
Income before taxes	24,169	27,948	22,555	22,024	24,237	25,042	24,686	17,515
Provision for income taxes	6,510	7,367	5,496	5,931	6,814	6,407	6,498	4,680	25,305	24,398	17,515
Net Income Available to Common Shareholders	$ 17,659	$ 20,581	$ 17,059	$ 16,093	$ 17,423	$ 18,635	$ 18,188	$ 12,835	$ 71,167	$ 66,801	$ 57,745
Common earnings per share-diluted (in USD per share)	$ 0.51	$ 0.59	$ 0.49	$ 0.46	$ 0.50	$ 0.54	$ 0.52	$ 0.41	$ 2.05	$ 1.98	$ 1.95
Dividends declared per common share (in USD per share)	0.20	0.19	0.19	0.19	0.19	0.18	0.18	0.18	$ 0.77	$ 0.73	$ 0.68
Common book value (in USD per share)	$ 24.12	$ 24.02	$ 23.63	$ 23.23	$ 22.76	$ 22.63	$ 22.15	$ 21.91