Century Bancorp (CNBKA) 10-Q 8 Aug 16 2016 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2016	Jul. 31, 2016
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q2
Trading Symbol	CNBKA
Entity Registrant Name	CENTURY BANCORP INC
Entity Central Index Key	812,348
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Class A Common Stock [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		3,600,729
Class B Common Stock [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		1,967,180

Consolidated Balance Sheets (un

Consolidated Balance Sheets (unaudited) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Assets
Cash and due from banks	$ 66,913	$ 52,877
Federal funds sold and interest-bearing deposits in other banks	20,093	167,847
Total cash and cash equivalents	87,006	220,724
Short-term investments	3,241	3,233
Securities available-for-sale, amortized cost $563,386 and $404,977, respectively	562,933	404,623
Securities held-to-maturity, fair value $1,606,758 and $1,438,960, respectively	1,573,829	1,438,903
Federal Home Loan Bank of Boston stock, at cost	26,086	28,807
Loans held-for-sale	12,403
Loans, net:
Commercial and industrial	493,033	452,235
Municipal	134,386	85,685
Construction and land development	31,178	27,421
Commercial real estate	728,658	721,506
Residential real estate	219,494	255,346
Home equity	183,816	178,020
Consumer and other	11,339	11,323
Total loans, net	1,801,904	1,731,536
Less: allowance for loan losses	23,863	23,075
Net loans	1,778,041	1,708,461
Bank premises and equipment	23,525	24,106
Accrued interest receivable	8,714	8,002
Goodwill	2,714	2,714
Other assets	111,820	107,868
Total assets	4,190,312	3,947,441
Deposits:
Demand deposits	610,756	541,955
Savings and NOW deposits	1,272,221	1,070,585
Money market accounts	875,428	989,094
Time deposits	460,527	473,426
Total deposits	3,218,932	3,075,060
Securities sold under agreements to repurchase	217,765	197,850
Other borrowed funds	431,000	368,000
Subordinated debentures	36,083	36,083
Due to broker	3,585	405
Other liabilities	55,761	55,499
Total liabilities	3,963,126	3,732,897
Stockholders' Equity
Preferred stock-$1.00 par value; 100,000 shares authorized; no shares issued and outstanding
Additional paid-in capital	12,292	12,292
Retained earnings	231,680	221,232
Stockholders' equity before adjustment of accumulated other comprehensive income (loss)	249,540	239,092
Unrealized losses on securities available-for-sale, net of taxes	(284)	(246)
Unrealized losses on securities transferred to held-to-maturity, net of taxes	(5,149)	(6,896)
Pension liability, net of taxes	(16,921)	(17,406)
Total accumulated other comprehensive loss, net of taxes	(22,354)	(24,548)
Total stockholders' equity	227,186	214,544
Total liabilities and stockholders' equity	4,190,312	3,947,441
Class A Common Stock [Member]
Stockholders' Equity
Common stock value	3,601	3,601
Total stockholders' equity	3,601	3,601
Class B Common Stock [Member]
Stockholders' Equity
Common stock value	1,967	1,967
Total stockholders' equity	$ 1,967	$ 1,967

Consolidated Balance Sheets (u3

Consolidated Balance Sheets (unaudited) (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Amortized cost	$ 563,386	$ 404,977
Held-to-maturity securities, fair value	$ 1,606,758	$ 1,438,960
Preferred stock, par value	$ 1	$ 1
Preferred stock, shares authorized	100,000	100,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Class A Common Stock [Member]
Common stock, par value	$ 1	$ 1
Common stock, shares authorized	10,000,000	10,000,000
Common stock, shares issued	3,600,729	3,600,729
Class B Common Stock [Member]
Common stock, par value	$ 1	$ 1
Common stock, shares authorized	5,000,000	5,000,000
Common stock, shares issued	1,967,180	1,967,180

Consolidated Statements of Inco

Consolidated Statements of Income (unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Interest income
Loans	$ 14,163	$ 12,470	$ 28,335	$ 24,546
Securities held-to-maturity	8,128	9,371	15,940	17,539
Securities available-for-sale	1,143	737	2,107	1,469
Federal funds sold and interest-bearing deposits in other banks	308	97	623	293
Total interest income	23,742	22,675	47,005	43,847
Interest expense
Savings and NOW deposits	938	692	1,776	1,320
Money market accounts	781	734	1,576	1,516
Time deposits	1,394	1,207	2,752	2,363
Securities sold under agreements to repurchase	126	128	241	242
Other borrowed funds and subordinated debentures	2,247	2,200	4,554	4,285
Total interest expense	5,486	4,961	10,899	9,726
Net interest income	18,256	17,714	36,106	34,121
Provision for loan losses	350		800	200
Net interest income after provision for loan losses	17,906	17,714	35,306	33,921
Other operating income
Service charges on deposit accounts	1,962	1,934	3,899	3,847
Lockbox fees	883	888	1,672	1,676
Net gains on sales of securities	45	118	45	118
Gains on sales of mortgage loans	798	418	798	517
Other income	955	852	1,883	1,557
Total other operating income	4,643	4,210	8,297	7,715
Operating expenses
Salaries and employee benefits	10,040	9,480	19,816	18,614
Occupancy	1,551	1,517	3,130	3,122
Equipment	679	659	1,315	1,252
FDIC assessments	592	545	1,160	1,048
Other	3,426	3,565	6,549	6,268
Total operating expenses	16,288	15,766	31,970	30,304
Income before income taxes	6,261	6,158	11,633	11,332
Provision for income taxes	20	233	84	448
Net income	6,241	5,925	11,549	10,884
Class A Common Stock [Member]
Operating expenses
Net income	$ 4,902	$ 4,654	$ 9,071	$ 8,549
Share data:
Weighted average number of shares outstanding, basic	3,600,729	3,600,729	3,600,729	3,600,729
Weighted average number of shares outstanding, diluted	5,567,909	5,567,909	5,567,909	5,567,909
Basic earnings per share	$ 1.36	$ 1.29	$ 2.52	$ 2.37
Diluted earnings per share	$ 1.12	$ 1.06	$ 2.07	$ 1.95
Class B Common Stock [Member]
Operating expenses
Net income	$ 1,339	$ 1,271	$ 2,478	$ 2,335
Share data:
Weighted average number of shares outstanding, basic	1,967,180	1,967,180	1,967,180	1,967,180
Weighted average number of shares outstanding, diluted	1,967,180	1,967,180	1,967,180	1,967,180
Basic earnings per share	$ 0.68	$ 0.65	$ 1.26	$ 1.19
Diluted earnings per share	$ 0.68	$ 0.65	$ 1.26	$ 1.19

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 6,241	$ 5,925	$ 11,549	$ 10,884
Unrealized gains (losses) on securities:
Unrealized (losses) gains arising during period	(325)	1	(11)	(29)
Less: reclassification adjustment for gains included in net income	(27)	(71)	(27)	(71)
Total unrealized (losses) gains on securities	(352)	(70)	(38)	(100)
Accretion of net unrealized losses transferred	762	1,027	1,747	1,762
Defined benefit pension plans:
Amortization of prior service cost and loss included in net periodic benefit cost	243	213	485	426
Other comprehensive income	653	1,170	2,194	2,088
Comprehensive income	$ 6,894	$ 7,095	$ 13,743	$ 12,972

Consolidated Statements of Chan

Consolidated Statements of Changes in Stockholders' Equity (unaudited) - USD ($) $ in Thousands	Total	Class A Common Stock [Member]	Class B Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Retained Earnings [Member]Class A Common Stock [Member]	Retained Earnings [Member]Class B Common Stock [Member]	Accumulated Other Comprehensive Loss [Member]
Beginning balance at Dec. 31, 2014	$ 192,500	$ 3,601	$ 1,967	$ 12,292	$ 200,411			$ (25,771)
Net income	10,884	8,549	2,335		10,884
Other comprehensive income, net of tax:
Unrealized holding (losses) gains arising during period, net of taxes	(100)							(100)
Accretion of unrealized losses on securities transferred to held-to-maturity net of taxes	1,762							1,762
Pension liability adjustment, net of taxes	426							426
Cash dividends	(865)					$ (865)	$ (234)
Ending balance at Jun. 30, 2015	204,373	3,601	1,967	12,292	210,196			(23,683)
Beginning balance at Dec. 31, 2015	214,544	3,601	1,967	12,292	221,232			(24,548)
Net income	11,549	9,071	2,478		11,549
Other comprehensive income, net of tax:
Unrealized holding (losses) gains arising during period, net of taxes	(38)							(38)
Accretion of unrealized losses on securities transferred to held-to-maturity net of taxes	1,747							1,747
Pension liability adjustment, net of taxes	485							485
Cash dividends	(866)					$ (866)	$ (235)
Ending balance at Jun. 30, 2016	$ 227,186	$ 3,601	$ 1,967	$ 12,292	$ 231,680			$ (22,354)

Consolidated Statements of Cha7

Consolidated Statements of Changes in Stockholders' Equity (unaudited) (Parenthetical) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Unrealized holding (losses) gains arising during period, taxes	$ 61	$ 64
Realized net gains	45	118
Accretion of net unrealized losses transferred during the period, taxes	935	943
Pension liability adjustment, taxes	$ 322	$ 284
Class A Common Stock [Member]
Cash dividends, per share	$ 0.24	$ 0.24
Class B Common Stock [Member]
Cash dividends, per share	$ 0.12	$ 0.12

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (unaudited) - USD ($)	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 11,549,000	$ 10,884,000
Adjustments to reconcile net income to net cash (used in) provided by operating activities:
Gain on sales of mortgage loans	(798,000)	(517,000)
Net gains on sales of securities	(45,000)	(118,000)
Provision for loan losses	800,000	200,000
Deferred income taxes	(1,792,000)	(819,000)
Net depreciation and amortization	1,575,000	1,639,000
Increase in accrued interest receivable	(712,000)	(1,040,000)
Increase in other assets	(3,428,000)	(13,357,000)
Increase in other liabilities	1,069,000	632,000
Net cash provided by (used in) operating activities	8,218,000	(2,496,000)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of short-term investments	(8,000)	(8,000)
Proceeds from redemptions of Federal Home Loan Bank of Boston stock	4,898,000
Purchase of Federal Home Loan Bank of Boston stock	(2,177,000)
Proceeds from calls/maturities of securities available-for-sale	130,513,000	91,052,000
Proceeds from sales of securities available-for-sale	1,946,000	21,215,000
Purchase of securities available-for-sale	(287,834,000)	(115,690,000)
Proceeds from calls/maturities of securities held-to-maturity	213,337,000	169,457,000
Proceeds from sales of securities held-to-maturity	192,000	0
Purchase of securities held-to-maturity	(345,692,000)	(443,705,000)
Net increase in loans	(132,182,000)	(249,003,000)
Proceeds from sales of portfolio loans	50,220,000	35,941,000
Capital expenditures	(835,000)	(1,520,000)
Net cash used in investing activities	(367,622,000)	(492,261,000)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net decrease in time deposits	(12,899,000)	139,000
Net increase in demand, savings, money market and NOW deposits	156,771,000	113,959,000
Cash dividends	(1,101,000)	(1,099,000)
Net increase in securities sold under agreements to repurchase	19,915,000	71,470,000
Net decrease in other borrowed funds	63,000,000	90,000,000
Net cash provided by financing activities	225,686,000	274,469,000
Net decrease in cash and cash equivalents	(133,718,000)	(220,288,000)
Cash and cash equivalents at beginning of period	220,724,000	305,357,000
Cash and cash equivalents at end of period	87,006,000	85,069,000
Cash paid during the period for:
Interest	10,893,000	9,646,000
Income taxes	2,110,000	2,730,000
Change in unrealized gains (losses) on securities available-for-sale, net of taxes	(38,000)	(100,000)
Change in unrealized losses on securities transferred to held-to-maturity, net of taxes	1,747,000	1,762,000
Pension liability adjustment, net of taxes	485,000	426,000
Change in due to (from) to broker	3,180,000	(8,764,000)
Loans transferred to other real estate owned		$ 1,916,000
Transfer of loans to loans held-for-sale	$ 12,403,000

Basis of Financial Statement Pr

Basis of Financial Statement Presentation	6 Months Ended
	Jun. 30, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Financial Statement Presentation	Note 1. Basis of Financial Statement Presentation The consolidated financial statements include the accounts of Century Bancorp, Inc. (the “Company”) and its wholly owned subsidiary, Century Bank and Trust Company (the “Bank”). The consolidated financial statements also include the accounts of the Bank’s wholly owned subsidiaries, Century Subsidiary Investments, Inc. (“CSII”), Century Subsidiary Investments, Inc. II (“CSII II”), Century Subsidiary Investments, Inc. III (“CSII III”) and Century Financial Services Inc. (“CFSI”). CSII, CSII II, and CSII III are engaged in buying, selling and holding investment securities. CFSI has the power to engage in financial agency, securities brokerage, and investment and financial advisory services and related securities credit. The Company also owns 100% of Century Bancorp Capital Trust II (“CBCT II”). The entity is an unconsolidated subsidiary of the Company. All significant intercompany accounts and transactions have been eliminated in consolidation. The Company provides a full range of banking services to individual, business and municipal customers in Massachusetts. As a bank holding company, the Company is subject to the regulation and supervision of the Federal Reserve Board. The Bank, a state chartered financial institution, is subject to supervision and regulation by applicable state and federal banking agencies, including the Federal Reserve Board, the Federal Deposit Insurance Corporation (the “FDIC”) and the Commonwealth of Massachusetts Commissioner of Banks. The Bank is also subject to various requirements and restrictions under federal and state law, including requirements to maintain reserves against deposits, restrictions on the types and amounts of loans that may be granted and the interest that may be charged thereon, and limitations on the types of investments that may be made and the types of services that may be offered. Various consumer laws and regulations also affect the operations of the Bank. In addition to the impact of regulation, commercial banks are affected significantly by the actions of the Federal Reserve Board as it attempts to control the money supply and credit availability in order to influence the economy. All aspects of the Company’s business are highly competitive. The Company faces aggressive competition from other lending institutions and from numerous other providers of financial services. The Company has one reportable operating segment. The financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America and general practices within the banking industry. In preparing the financial statements, management is required to make estimates and assumptions that affect the reported amounts of assets and liabilities as of the date of the balance sheet and revenues and expenses for the period. Actual results could differ from those estimates. The Company’s quarterly report on Form 10-Q should be read in conjunction with the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2015, as filed with the Securities and Exchange Commission. Material estimates that are susceptible to change in the near term relate to the allowance for loan losses. Management believes that the allowance for loan losses is adequate based on independent appraisals and review of other factors, including historical charge-off rates with additional allocations based on risk factors for each category and general economic factors. While management uses available information to recognize loan losses, future additions to the allowance for loan losses may be necessary based on changes in economic conditions. In addition, regulatory agencies periodically review the Company’s allowance for loan losses. Such agencies may require the Company to recognize additions to the allowance for loan losses based on their judgments about information available to them at the time of their examination. Certain reclassifications are made to prior-year amounts whenever necessary to conform with the current-year presentation.

Securities Available-for-Sale

Securities Available-for-Sale	6 Months Ended
	Jun. 30, 2016
Text Block [Abstract]
Securities Available-for-Sale	Note 2. Securities Available-for-Sale June 30, 2016 December 31, 2015 Amortized Gross Gross Fair Amortized Gross Gross Fair (in thousands) U.S. Treasury $ 1,999 $ 1 $ — $ 2,000 $ 1,999 $ — $ 10 $ 1,989 U.S. Government Sponsored Enterprises 15,000 24 — 15,024 — — — — SBA Backed Securities 45,698 31 24 45,705 5,983 8 2 5,989 U.S. Government Agency and Sponsored Enterprise Mortgage-Backed Securities 280,931 434 488 280,877 232,967 859 300 233,526 Privately Issued Residential Mortgage-Backed Securities 1,301 2 17 1,286 1,437 10 13 1,434 Obligations Issued by States and Political Subdivisions 213,241 — 403 212,838 157,838 — 878 156,960 Other Debt Securities 5,100 — 158 4,942 4,600 3 130 4,473 Equity Securities 116 145 — 261 153 99 — 252 Total $ 563,386 $ 637 $ 1,090 $ 562,933 $ 404,977 $ 979 $ 1,333 $ 404,623 Included in U.S. Government Sponsored Enterprise Securities and U.S. Government Agency and Sponsored Enterprise Mortgage-Backed Securities are securities at fair value pledged to secure public deposits and repurchase agreements amounting to $220,489,000 and $220,482,000 at June 30, 2016 and December 31, 2015, respectively. Also included in securities available-for-sale are securities pledged for borrowing at the Federal Home Loan Bank of Boston amounting to $66,454,000 and $20,056,000 at June 30, 2016 and December 31, 2015, respectively. The Company realized gross gains of $33,000 from the proceeds of $1,946,000 from the sales of available-for-sale securities for the six months ended June 30, 2016. The Company realized gross gains of $118,000 from the proceeds of $21,215,000 from the sales of available-for-sale securities for the six months ended June 30, 2015. Debt securities of Government Sponsored Enterprises primarily refer to debt securities of Fannie Mae and Freddie Mac. The following table shows the maturity distribution of the Company’s securities available-for-sale at June 30, 2016. Amortized Fair (in thousands) Within one year $ 217,903 $ 217,912 After one but within five years 232,419 232,311 After five but within ten years 105,748 105,767 More than 10 years 5,700 5,292 Non-maturing 1,616 1,651 Total $ 563,386 $ 562,933 The weighted average remaining life of investment securities available-for-sale at June 30, 2016 was 3.5 years. Included in the weighted average remaining life calculation at June 30, 2016 were $15,000,000 of U.S. Government Sponsored Enterprises obligations that are callable at the discretion of the issuer. The contractual maturities, which were used in the table above, of mortgage-backed securities, will differ from the actual maturities, due to the ability of the issuers to prepay underlying obligations. As of June 30, 2016 and December 31, 2015, management concluded that the unrealized losses of its investment securities are temporary in nature since they are not related to the underlying credit quality of the issuers, and the Company does not intend to sell these debt securities and it is not more likely than not that it will be required to sell these debt securities before the anticipated recovery of its remaining amortized cost. In making its other-than-temporary impairment evaluation, the Company considered that the principal and interest on these securities are from issuers that are investment grade. The change in the unrealized losses on the state and municipal securities and the nonagency mortgage-backed securities was primarily caused by changes in credit spreads and liquidity issues in the marketplace. The unrealized loss on U.S. Treasury, SBA Backed Securities, and U.S. Government Agency and Sponsored Enterprise Mortgage Backed Securities, related primarily to interest rates and not credit quality, and because the Company has the ability and intent to hold these investments until recovery of fair value, which may be maturity, the Company does not consider these investments to be other-than-temporarily impaired. In evaluating the underlying credit quality of a security, management considers several factors such as the credit rating of the obligor and the issuer, if applicable. Internal reviews of issuer financial statements are performed as deemed necessary. In the case of privately issued mortgage-backed securities, the performance of the underlying loans is analyzed as deemed necessary to determine the estimated future cash flows of the securities. Factors considered include the level of subordination, current and estimated future default rates, current and estimated prepayment rates, estimated loss severity rates, geographic concentrations and origination dates of underlying loans. In the case of marketable equity securities, the severity of the unrealized loss, the length of time the unrealized loss has existed, and the issuer’s financial performance are considered. The following table shows the temporarily impaired securities of the Company’s available-for-sale portfolio at June 30, 2016. This table shows the unrealized market loss of securities that have been in a continuous unrealized loss position for less than 12 months and a continuous loss position for 12 months or longer. There are 37 and 10 securities that are temporarily impaired for less than 12 months and for 12 months or longer, respectively, out of a total of 327 holdings at June 30, 2016. June 30, 2016 Less than 12 months 12 months or longer Total Temporarily Impaired Investments Fair Unrealized Fair Unrealized Fair Unrealized (in thousands) U.S. Treasury $ — $ — $ — $ — $ — $ — SBA Backed Securities 10,959 24 — — 10,959 24 U.S. Government Agency and Sponsored Enterprise Mortgage-Backed Securities 127,281 372 27,894 116 155,175 488 Privately Issued Residential Mortgage-Backed Securities 415 2 467 15 882 17 Obligations Issued by States and Political Subdivisions — — 4,298 403 4,298 403 Other Debt Securities 1,553 47 1,789 111 3,342 158 Total temporarily impaired securities $ 140,208 $ 445 $ 34,448 $ 645 $ 174,656 $ 1,090 The following table shows the temporarily impaired securities of the Company’s available-for-sale portfolio at December 31, 2015. This table shows the unrealized market loss of securities that have been in a continuous unrealized loss position for less than 12 months and a continuous loss position for 12 months or longer. There are 14 and 11 securities that are temporarily impaired for less than 12 months and for 12 months or longer, respectively, out of a total of 290 holdings at December 31, 2015. December 31, 2015 Less than 12 months 12 months or longer Total Temporarily Impaired Investments Fair Unrealized Fair Unrealized Fair Unrealized (in thousands) U.S. Treasury $ 1,989 $ 10 $ — $ — $ 1,989 $ 10 SBA Backed Securities 1,031 2 — — 1,031 2 U.S. Government Agency and Sponsored Enterprise Mortgage-Backed Securities 26,519 52 49,341 248 75,860 300 Privately Issued Residential Mortgage-Backed Securities — — 490 13 490 13 Obligations Issued by States and Political Subdivisions — — 3,820 878 3,820 878 Other Debt Securities 497 3 1,373 127 1,870 130 Total temporarily impaired securities $ 30,036 $ 67 $ 55,024 $ 1,266 $ 85,060 $ 1,333

Investment Securities Held-to-M

Investment Securities Held-to-Maturity	6 Months Ended
	Jun. 30, 2016
Text Block [Abstract]
Investment Securities Held-to-Maturity	Note 3. Investment Securities Held-to-Maturity June 30, 2016 December 31, 2015 Amortized Gross Gross Estimated Amortized Gross Gross Estimated (in thousands) U.S. Government Sponsored Enterprises $ 190,026 $ 3,240 $ 1 $ 193,265 $ 186,734 $ 2,234 $ 141 $ 188,827 SBA Backed Securities 20,987 155 — 21,142 — — — — U.S. Government Agency and Sponsored Enterprises Mortgage-Backed Securities 1,362,816 30,164 629 1,392,351 1,252,169 7,547 9,583 1,250,133 Total $ 1,573,829 $ 33,559 $ 630 $ 1,606,758 $ 1,438,903 $ 9,781 $ 9,724 $ 1,438,960 Included in U.S. Government and Agency Securities are securities pledged to secure public deposits and repurchase agreements at fair value amounting to $1,185,127,000 and $1,004,743,000 at June 30, 2016 and December 31, 2015, respectively. Also included are securities pledged for borrowing at the Federal Home Loan Bank of Boston at fair value amounting to $356,261,000 and $432,965,000 at June 30, 2016 and December 31, 2015, respectively. The Company realized gross gains of $12,000 from the proceeds of $192,000 from the sales of securities held-to-maturity for the six months ended June 30, 2016. The sales of securities held-to-maturity relate to certain mortgage-backed securities for which the Company had previously collected a substantial portion of its principal investment. There were no sales of held-to-maturity securities for the six months ended June 30, 2015. At June 30, 2016 and December 31, 2015, all mortgage-backed securities are obligations of U.S. Government Agencies and Government Sponsored Enterprises. U.S. Government Sponsored Enterprises primarily refer to debt securities of Fannie Mae and Freddie Mac. The following table shows the maturity distribution of the Company’s securities held-to-maturity at June 30, 2016. Amortized Fair (in thousands) Within one year $ 10,047 $ 10,137 After one but within five years 1,400,716 1,427,594 After five but within ten years 159,917 165,817 More than ten years 3,149 3,210 Total $ 1,573,829 $ 1,606,758 The weighted average remaining life of investment securities held-to-maturity at June 30, 2016 was 3.8 years. Included in the weighted average remaining life calculation at June 30, 2016 were $101,745,000 of U.S. Government Sponsored Enterprises obligations that are callable at the discretion of the issuer. The actual maturities, which were used in the table above, of mortgage-backed securities, will differ from the contractual maturities, due to the ability of the issuers to prepay underlying obligations. As of June 30, 2016 and December 31, 2015, management concluded that the unrealized losses of its investment securities are temporary in nature since they are not related to the underlying credit quality of the issuers, and the Company does not intend to sell these debt securities and it is not likely that it will be required to sell these debt securities before the anticipated recovery of their remaining amortized costs. In making its other-than-temporary impairment evaluation, the Company considered the fact that the principal and interest on these securities are from issuers that are investment grade. The unrealized loss on U.S. Government Sponsored Enterprises and U.S. Government Agency and Sponsored Enterprise Mortgage-Backed Securities related primarily to interest rates and not credit quality, and because the Company does not intend to sell any of these securities and it is not likely that it will be required to sell these securities before the anticipated recovery of the remaining amortized cost, the Company does not consider these investments to be other-than-temporarily impaired June 30, 2016 and December 31, 2015. In evaluating the underlying credit quality of a security, management considers several factors such as the credit rating of the obligor and the issuer, if applicable. Internal reviews of issuer financial statements are performed as deemed necessary. The following table shows the temporarily impaired securities of the Company’s held-to-maturity portfolio at June 30, 2016. This table shows the unrealized market loss of securities that have been in a continuous unrealized loss position for 12 months or less and a continuous loss position for 12 months or longer. There are 6 and 16 securities that are temporarily impaired for less than 12 months and for 12 months or longer, respectively, out of a total of 352 holdings at June 30, 2016. June 30, 2016 Less Than 12 Months 12 Months or Longer Total Temporarily Impaired Investments Fair Unrealized Fair Unrealized Fair Unrealized (in thousands) U.S. Government Sponsored Enterprises $ 14,999 $ 1 $ — $ — $ 14,999 $ 1 U.S. Government Agency and Sponsored Enterprise Mortgage-Backed Securities 23,087 93 70,461 536 93,548 629 Total temporarily impaired securities $ 38,086 $ 94 $ 70,461 $ 536 $ 108,547 $ 630 The following table shows the temporarily impaired securities of the Company’s held-to-maturity portfolio at December 31, 2015. This table shows the unrealized market loss of securities that have been in a continuous unrealized loss position for less than 12 months and a continuous loss position for 12 months or longer. There are 101 and 26 securities that are temporarily impaired for less than 12 months and for 12 months or longer, respectively, out of a total of 322 holdings at December 31, 2015. December 31, 2015 Less Than 12 Months 12 Months or Longer Total Temporarily Impaired Investments Fair Unrealized Fair Unrealized Fair Unrealized (in thousands) U.S. Government Sponsored Enterprises $ 9,859 $ 141 $ — $ — $ 9,859 $ 141 U.S. Government Agency and Sponsored Enterprise Mortgage-Backed Securities 626,218 6,657 123,864 2,926 750,082 9,583 Total temporarily impaired securities $ 636,077 $ 6,798 $ 123,864 $ 2,926 $ 759,941 $ 9,724

Allowance for Loan Losses

Allowance for Loan Losses	6 Months Ended
	Jun. 30, 2016
Receivables [Abstract]
Allowance for Loan Losses	Note 4. Allowance for Loan Losses The Company maintains an allowance for loan losses in an amount determined by management on the basis of the character of the loans, loan performance, financial condition of borrowers, the value of collateral securing loans and other relevant factors. The following table summarizes the changes in the Company’s allowance for loan losses for the periods indicated. Three months ended Six months ended 2016 2015 2016 2015 (in thousands) Allowance for loan losses, beginning of period $ 23,544 $ 22,529 $ 23,075 $ 22,318 Loans charged off (111 ) (403 ) (180 ) (484 ) Recoveries on loans previously charged-off 164 119 252 211 Net recoveries (charge-offs) 53 (284 ) 72 (273 ) Provision charged to expense 350 — 800 200 Reclassification to other liabilities* (84 ) — (84 ) — Allowance for loan losses, end of period $ 23,863 $ 22,245 $ 23,863 $ 22,245 * The reclassification relates to allowance for loan losses allocations on unused commitments that have been reclassified to other liabilities. Further information pertaining to the allowance for loan losses for the three months ending June 30, 2016 follows: Construction Commercial Municipal Commercial Residential Consumer Home Unallocated Total (in thousands) Allowance for loan losses: Balance at March 31, 2016 $ 1,973 $ 6,693 $ 990 $ 10,533 $ 1,249 $ 693 $ 1,185 $ 228 $ 23,544 Charge-offs — — — — — (111 ) — — (111 ) Recoveries — 56 — — 2 106 — — 164 Provision 264 (878 ) 811 128 53 (77 ) 9 40 350 Reclassification to other liabilities (3 ) (29 ) — (11 ) (2 ) (3 ) (36 ) — (84 ) Ending balance at June 30, 2016 $ 2,234 $ 5,842 $ 1,801 $ 10,650 $ 1,302 $ 608 $ 1,158 $ 268 $ 23,863 Amount of allowance for loan losses for loans deemed to be impaired $ 6 $ 10 $ — $ 151 $ 7 $ — $ — $ — $ 174 Amount of allowance for loan losses for loans not deemed to be impaired $ 2,228 $ 5,832 $ 1,801 $ 10,499 $ 1,295 $ 608 $ 1,158 $ 268 $ 23,689 Loans: Ending balance $ 31,178 $ 493,033 $ 134,386 $ 728,658 $ 219,494 $ 11,339 $ 183,816 $ — $ 1,801,904 Loans deemed to be impaired $ 96 $ 410 $ — $ 3,736 $ 215 $ — $ — $ — $ 4,457 Loans not deemed to be impaired $ 31,082 $ 492,623 $ 134,386 $ 724,922 $ 219,279 $ 11,339 $ 183,816 $ — $ 1,797,447 Further information pertaining to the allowance for loan losses for the six months ending June 30, 2016 follows: Construction and Land Commercial and Municipal Commercial Residential Consumer Home Unallocated Total (in thousands) Allowance for loan losses: Balance at December 31, 2015 $ 2,041 $ 5,899 $ 994 $ 10,589 $ 1,320 $ 644 $ 1,077 $ 511 $ 23,075 Charge-offs — — — — — (180 ) — — (180 ) Recoveries — 91 — — 3 158 — — 252 Provision 196 (119 ) 807 72 (19 ) (11 ) 117 (243 ) 800 Reclassification to other liabilities (3 ) (29 ) — (11 ) (2 ) (3 ) (36 ) — (84 ) Ending balance at June 30, 2016 $ 2,234 $ 5,842 $ 1,801 $ 10,650 $ 1,302 $ 608 $ 1,158 $ 268 $ 23,863 Amount of allowance for loan losses for loans deemed to be impaired $ 6 $ 10 $ — $ 151 $ 7 $ — $ — $ — $ 174 Amount of allowance for loan losses for loans not deemed to be impaired $ 2,228 $ 5,832 $ 1,801 $ 10,499 $ 1,295 $ 608 $ 1,158 $ 268 $ 23,689 Loans: Ending balance $ 31,178 $ 493,033 $ 134,386 $ 728,658 $ 219,494 $ 11,339 $ 183,816 $ — $ 1,801,904 Loans deemed to be impaired $ 96 $ 410 $ — $ 3,736 $ 215 $ — $ — $ — $ 4,457 Loans not deemed to be impaired $ 31,082 $ 492,623 $ 134,386 $ 724,922 $ 219,279 $ 11,339 $ 183,816 $ — $ 1,797,447 During the six months ending June 30, 2016, the Company’s provision was primarily attributable to an increase in municipal balances. During the three months ending June 30, 2016 the Company’s provision was primarily attributable to an increase in construction loan balances. There was also an increase in municipal originations, which increased the municipal allocation and commercial and industrial loan payoffs, which decreased the commercial and industrial allocations. Further information pertaining to the allowance for loan losses for the three months ending June 30, 2015 follows: Construction and Land Commercial and Municipal Commercial Residential Consumer Home Unallocated Total (in thousands) Allowance for loan losses: Balance at March 31, 2015 $ 1,884 $ 4,645 $ 1,373 $ 11,127 $ 799 $ 714 $ 614 $ 1,373 $ 22,529 Charge-offs — (52 ) — (298 ) — (53 ) — — (403 ) Recoveries — 56 — 2 2 59 — — 119 Provision (151 ) (221 ) (373 ) 892 (79 ) (11 ) 36 (93 ) — Ending balance at June 30, 2015 $ 1,733 $ 4,428 $ 1,000 $ 11,723 $ 722 $ 709 $ 650 $ 1,280 $ 22,245 Amount of allowance for loan losses for loans deemed to be impaired $ 12 $ 43 $ — $ 108 $ 41 $ — $ 91 $ — $ 295 Amount of allowance for loan losses for loans not deemed to be impaired $ 1,721 $ 4,385 $ 1,000 $ 11,615 $ 681 $ 709 $ 559 $ 1,280 $ 21,950 Loans: Ending balance $ 26,521 $ 291,142 $ 87,241 $ 713,770 $ 248,103 $ 10,646 $ 167,271 $ — $ 1,544,694 Loans deemed to be impaired $ 101 $ 595 $ — $ 1,705 $ 941 $ — $ 91 $ — $ 3,433 Loans not deemed to be impaired $ 26,420 $ 290,547 $ 87,241 $ 712,065 $ 247,162 $ 10,646 $ 167,180 $ — $ 1,541,261 Further information pertaining to the allowance for loan losses for the six months ending June 30, 2015 follows: Construction and Land Commercial and Municipal Commercial Residential Consumer Home Unallocated Total (in thousands) Allowance for loan losses: Balance at December 31, 2104 $ 1,592 $ 4,758 $ 1,488 $ 11,199 $ 775 $ 810 $ 599 $ 1,097 $ 22,318 Charge-offs — (52 ) — (298 ) — (134 ) — — (484 ) Recoveries — 71 — 4 4 132 — — 211 Provision 141 (349 ) (488 ) 818 (57 ) (99 ) 51 183 200 Ending balance at June 30, 2015 $ 1,733 $ 4,428 $ 1,000 $ 11,723 $ 722 $ 709 $ 650 $ 1,280 $ 22,245 Amount of allowance for loan losses for loans deemed to be impaired $ 12 $ 43 $ — $ 108 $ 41 $ — $ 91 $ — $ 295 Amount of allowance for loan losses for loans not deemed to be impaired $ 1,721 $ 4,385 $ 1,000 $ 11,615 $ 681 $ 709 $ 559 $ 1,280 $ 21,950 Loans: Ending balance $ 26,521 $ 291,142 $ 87,241 $ 713,770 $ 248,103 $ 10,646 $ 167,271 $ — $ 1,544,694 Loans deemed to be impaired $ 101 $ 595 $ — $ 1,705 $ 941 $ — $ 91 $ — $ 3,433 Loans not deemed to be impaired $ 26,420 $ 290,547 $ 87,241 $ 712,065 $ 247,162 $ 10,646 $ 167,180 $ — $ 1,541,261 The Company utilizes a six grade internal loan rating system for commercial real estate, construction and commercial loans as follows: Loans rated 1-3 (Pass): Loans in this category are considered “pass” rated loans with low to average risk. Loans rated 4 (Monitor): These loans represent classified loans that management is closely monitoring for credit quality. These loans have had or may have minor credit quality deterioration as of June 30, 2016 and December 31, 2015. Loans rated 5 (Substandard): Substandard loans represent classified loans that management is closely monitoring for credit quality. These loans have had more significant credit quality deterioration as of June 30, 2016 and December 31, 2015. Loans rated 6 (Doubtful): Doubtful loans represent classified loans that management is closely monitoring for credit quality. These loans had more significant credit quality deterioration as of June 30, 2016 and December 31, 2015 and are doubtful for full collection. Impaired: Impaired loans represent classified loans that management is closely monitoring for credit quality. A loan is classified as impaired when it is probable that the Company will be unable to collect all amounts due. The following table presents the Company’s loans by risk rating at June 30, 2016. Construction Commercial Municipal Commercial (in thousands) Grade: 1-3 (Pass) $ 24,048 $ 492,623 $ 134,386 $ 724,735 4 (Monitor) 7,034 — — 187 5 (Substandard) — — — — 6 (Doubtful) — — — — Impaired 96 410 — 3,736 Total $ 31,178 $ 493,033 $ 134,386 $ 728,658 The following table presents the Company’s loans by risk rating at December 31, 2015. Construction Commercial Municipal Commercial (in thousands) Grade: 1-3 (Pass) $ 20,281 $ 451,774 $ 85,685 $ 718,911 4 (Monitor) 7,042 18 — 917 5 (Substandard) — — — — 6 (Doubtful) — — — — Impaired 98 443 — 1,678 Total $ 27,421 $ 452,235 $ 85,685 $ 721,506 The Company has increased its exposure to larger loans to large institutions with publically available credit ratings beginning in 2015. These ratings are tracked as a credit quality indicator for these loans. Credit ratings issued by national organizations were utilized as credit quality indicators as presented in the following table at June 30, 2016. Commercial Municipal Commercial Total (in thousands) Credit Rating: Aaa – Aa3 $ 282,048 $ 68,806 $ 7,074 $ 357,928 A1 – A3 140,324 7,400 130,152 277,876 Baa1 – Baa3 — 53,520 166,105 219,625 Ba2 — 3,610 — 3,610 Total $ 422,372 $ 133,336 $ 303,331 $ 859,039 Credit ratings issued by national organizations were utilized as credit quality indicators as presented in the following table at December 31, 2015. Commercial Municipal Commercial Total (in thousands) Credit Rating: Aaa – Aa3 $ 234,733 $ 63,865 $ 7,547 $ 306,145 A1 – A3 140,419 7,400 130,872 278,691 Baa1 – Baa3 — 8,890 167,489 176,379 Ba2 — 4,480 — 4,480 Total $ 375,152 $ 84,635 $ 305,908 $ 765,695 The Company utilized payment performance as credit quality indicators for the loan types listed below. The indicators are depicted in the table “aging of past due loans,” below. Further information pertaining to the allowance for loan losses at June 30, 2016 follows: Accruing 30-89 Days Non Accruing Total Current Total (in thousands) Construction and land development $ — $ 96 $ — $ 96 $ 31,082 $ 31,178 Commercial and industrial 470 52 — 522 492,511 493,033 Municipal — — — — 134,386 134,386 Commercial real estate 1,080 162 — 1,242 727,416 728,658 Residential real estate 736 844 — 1,580 217,914 219,494 Consumer and overdrafts 1 3 — 4 11,335 11,339 Home equity 359 329 — 688 183,128 183,816 Total $ 2,646 $ 1,486 $ — $ 4,132 $ 1,797,772 $ 1,801,904 Further information pertaining to the allowance for loan losses at December 31, 2015 follows: Accruing 30-89 Days Non Accruing Total Current Total (in thousands) Construction and land development $ — $ 99 $ — $ 99 $ 27,322 $ 27,421 Commercial and industrial — 60 — 60 452,175 452,235 Municipal — — — — 85,685 85,685 Commercial real estate 1,462 174 — 1,636 719,870 721,506 Residential real estate 596 1,559 — 2,155 253,191 255,346 Consumer and overdrafts 6 — — 6 11,317 11,323 Home equity 628 444 — 1,072 176,948 178,020 Total $ 2,692 $ 2,336 $ — $ 5,028 $ 1,726,508 $ 1,731,536 A loan is impaired when, based on current information and events, it is probable that a creditor will be unable to collect all amounts due according to the contractual terms of the loan agreement. When a loan is impaired, the Company measures impairment based on the present value of expected future cash flows discounted at the loan’s effective interest rate, except that as a practical expedient, the Company measures impairment based on a loan’s observable market price or the fair value of the collateral if the loan is collateral dependent. Loans are charged-off when management believes that the collectability of the loan’s principal is not probable. The specific factors that management considers in making the determination that the collectability of the loan’s principal is not probable include: the delinquency status of the loan, the fair value of the collateral, if secured, and the financial strength of the borrower and/or guarantors. For collateral dependent loans, the amount of the recorded investment in a loan that exceeds the fair value of the collateral is charged-off against the allowance for loan losses in lieu of an allocation of a specific allowance amount when such an amount has been identified definitively as uncollectible. The Company’s policy for recognizing interest income on impaired loans is contained within Note 1 of the consolidated financial statements contained in the Company’s Annual Report for the fiscal year ended December 31, 2015. The following is information pertaining to impaired loans for June 30, 2016: Carrying Unpaid Required Average Interest Average Interest (in thousands) With no required reserve recorded: Construction and land development $ — $ — $ — $ — $ — $ — $ — Commercial and industrial 52 239 — 54 — 56 — Municipal — — — — — — — Commercial real estate 596 596 — 329 16 188 22 Residential real estate 103 190 — 106 2 108 4 Consumer — — — — — — — Home equity — — — — — — — Total $ 751 $ 1,025 $ — $ 489 $ 18 $ 352 $ 26 With required reserve recorded: Construction and land development $ 96 $ 108 $ 6 $ 97 $ — $ 97 $ — Commercial and industrial 358 373 10 370 5 374 9 Municipal — — — — — — — Commercial real estate 3,140 3,239 151 2,030 20 1,878 33 Residential real estate 112 112 7 283 1 505 3 Consumer — — — — — — — Home equity — — — 22 — 51 — Total $ 3,706 $ 3,832 $ 174 $ 2,802 $ 26 $ 2,905 $ 45 Total: Construction and land development $ 96 $ 108 $ 6 $ 97 $ — $ 97 $ — Commercial and industrial 410 612 10 424 5 430 9 Municipal — — — — — — — Commercial real estate 3,736 3,835 151 2,359 36 2,066 55 Residential real estate 215 302 7 389 3 613 7 Consumer — — — — — — — Home equity — — — 22 — 51 — Total $ 4,457 $ 4,857 $ 174 $ 3,291 $ 44 $ 3,257 $ 71 The following is information pertaining to impaired loans for June 30, 2015: Carrying Unpaid Required Average Interest Average Interest (in thousands) With no required reserve recorded: Construction and land development $ — $ — $ — $ — $ — $ — $ — Commercial and industrial 32 32 — 47 — 40 — Municipal — — — — — — — Commercial real estate — — — 196 — 280 — Residential real estate 126 210 — 129 2 131 4 Consumer — — — — — — — Home equity — — — — — — — Total $ 158 $ 242 $ — $ 372 $ 2 $ 451 $ 4 With required reserve recorded: Construction and land development $ 101 $ 108 $ 12 $ 102 $ — $ 102 $ — Commercial and industrial 563 765 43 644 5 722 11 Municipal — — — — — — — Commercial real estate 1,705 1,801 108 2,809 17 3,286 33 Residential real estate 815 815 41 817 1 820 7 Consumer — — — — — — — Home equity 91 91 91 91 — 92 — Total $ 3,275 $ 3,580 $ 295 $ 4,463 $ 23 $ 5,022 $ 51 Total: Construction and land development $ 101 $ 108 $ 12 $ 102 $ — $ 102 $ — Commercial and industrial 595 797 43 691 5 762 11 Municipal — — — — — — — Commercial real estate 1,705 1,801 108 3,005 17 3,566 33 Residential real estate 941 1,025 41 946 3 951 11 Consumer — — — — — — — Home equity 91 91 91 91 — 92 — Total $ 3,433 $ 3,822 $ 295 $ 4,835 $ 25 $ 5,473 $ 55 There was one commercial real estate troubled debt restructuring during the six month period ending June 30, 2016. The pre-modification and post-modification outstanding recorded investment was $2,091,000. The loan was modified for 2016, by reducing the interest rate as well as extending the term on the loan. The financial impact for the modification was $3,000 reduction in principal payments and $1,000 reduction in interest payments. There was no troubled debt restructuring during the six month period ended June 30, 2015.

Reclassifications Out of Accumu

Reclassifications Out of Accumulated Other Comprehensive Income	6 Months Ended
	Jun. 30, 2016
Text Block [Abstract]
Reclassifications Out of Accumulated Other Comprehensive Income	Note 5. Reclassifications Out of Accumulated Other Comprehensive Income Amount Reclassified from Accumulated Other Comprehensive Income Details about Accumulated Other Comprehensive Income Components Three Three Affected Line Item in the Statement where Net Income is Presented (in thousands) Unrealized gains and losses on available-for-sale securities $ 45 $ 118 Net gains on sales of investments Tax (expense) or benefit (18 ) (47 ) Provision for income taxes Net of tax $ 27 $ 71 Net income Accretion of unrealized losses transferred $ (1,170 ) $ (1,576 ) Interest on securities held-to-maturity Tax (expense) or benefit 408 549 Provision for income taxes Net of tax $ (762 ) $ (1,027 ) Net income Amortization of defined benefit pension items Prior-service costs $ (3 )(b) $ (3 )(b) Salaries and employee benefits Actuarial gains (losses) (401 )(b) (352 )(b) Salaries and employee benefits Total before tax (404 ) (355 ) Income before taxes Tax (expense) or benefit 161 142 Provision for income taxes Net of tax $ (243 ) $ (213 ) Net income Total reclassifications for the period $ (978 ) $ (1,169 ) Net income Details about Accumulated Other Comprehensive Income Components Six Six Affected Line Item in the Statement where Net Income is Presented (in thousands) Unrealized gains and losses on available-for-sale securities $ 45 $ 118 Net gains on sales of investments Tax (expense) or benefit (18 ) (47 ) Provision for income taxes Net of tax $ 27 $ 71 Net income Accretion of unrealized losses transferred $ (2,682 ) $ (2,705 ) Interest on securities held-to-maturity Tax (expense) or benefit 935 943 Provision for income taxes Net of tax $ (1,747 ) $ (1,762 ) Net income Amortization of defined benefit pension items Prior-service costs $ (5 )(b) $ (6 )(b) Salaries and employee benefits Actuarial gains (losses) (802 )(b) (704 )(b) Salaries and employee benefits Total before tax (807 ) (710 ) Income before taxes Tax (expense) or benefit 322 284 Provision for income taxes Net of tax $ (485 ) $ (426 ) Net income Total reclassifications for the period $ (2,205 ) $ (2,117 ) Net income, net of tax (a) Amount in parentheses indicates reductions to net income. (b) These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see Employee Benefits footnote (Note 7) for additional details).

Earnings per Share ("EPS")

Earnings per Share ("EPS")	6 Months Ended
	Jun. 30, 2016
Earnings Per Share [Abstract]
Earnings per Share ("EPS")	Note 6. Earnings per Share (“EPS”) Class A and Class B shares participate equally in undistributed earnings. Under the Company’s Articles of Organization, the holders of Class A Common Stock are entitled to receive dividends per share equal to at least 200% of dividends paid, if any, from time to time, on each share of Class B Common Stock. Diluted EPS includes the dilutive effect of common stock equivalents; basic EPS excludes all common stock equivalents. The Company had no common stock equivalents outstanding for the periods ended June 30, 2015 and 2016. The following table is a reconciliation of basic EPS and diluted EPS. Three Months Ended Six Months Ended (in thousands except share and per share data) 2016 2015 2016 2015 Basic EPS Computation: Numerator: Net income, Class A $ 4,902 $ 4,654 $ 9,071 $ 8,549 Net income, Class B 1,339 1,271 2,478 2,335 Denominator: Weighted average shares outstanding, Class A 3,600,729 3,600,729 3,600,729 3,600,729 Weighted average shares outstanding, Class B 1,967,180 1,967,180 1,967,180 1,967,180 Basic EPS, Class A $ 1.36 $ 1.29 $ 2.52 $ 2.37 Basic EPS, Class B 0.68 0.65 1.26 1.19 Diluted EPS Computation: Numerator: Net income, Class A $ 4,902 $ 4,654 $ 9,071 $ 8,549 Net income, Class B 1,339 1,271 2,478 2,335 Total net income, for diluted EPS, Class A computation 6,241 5,925 11,549 10,884 Denominator: Weighted average shares outstanding, basic, Class A 3,600,729 3,600,729 3,600,729 3,600,729 Weighted average shares outstanding, Class B 1,967,180 1,967,180 1,967,180 1,967,180 Weighted average shares outstanding diluted, Class A 5,567,909 5,567,909 5,567,909 5,567,909 Weighted average shares outstanding, Class B 1,967,180 1,967,180 1,967,180 1,967,180 Diluted EPS, Class A $ 1.12 $ 1.06 $ 2.07 $ 1.95 Diluted EPS, Class B 0.68 0.65 1.26 1.19

Employee Benefits

Employee Benefits	6 Months Ended
	Jun. 30, 2016
Compensation and Retirement Disclosure [Abstract]
Employee Benefits	Note 7. Employee Benefits The Company provides pension benefits to its employees under a noncontributory, defined benefit plan which is funded on a current basis in compliance with the requirements of the Employee Retirement Income Security Act of 1974 (“ERISA”) and recognizes costs over the estimated employee service period. The Company also has a Supplemental Executive Insurance/Retirement Plan (the “Supplemental Plan”) which is limited to certain officers and employees of the Company. The Supplemental Plan is accrued on a current basis and recognizes costs over the estimated employee service period. Executive officers of the Company and its subsidiaries who have at least one year of service may participate in the Supplemental Plan. The Supplemental Plan is voluntary and participants are required to contribute to its cost. Life insurance policies, which are owned by the Company, are purchased covering the lives of each participant. Effective January 1, 2016, the Company changed its estimate of the service and interest components of the net periodic benefit cost. Previously, the Company estimated the service and interest cost components utilizing a single weighted-average discount rate derived from the yield curve used to measure the benefit obligation. The new estimate utilizes a full yield curve approach in the estimation of these components by applying the specific spot rates along the yield curve used in the determination of the benefit obligation to their underlying projected cash flows. The new estimate provided a more precise measurement of service and interests costs by improving the correlation between projected benefit cash flows and their corresponding spot rates. The change does not affect the measurement of the Company’s benefit obligations and it is accounted for as a change in accounting estimate, which is applied prospectively. Components of Net Periodic Benefit Cost (Credit) for the Three Months Ended June 30, Pension Benefits Supplemental Insurance/ 2016 2015 2016 2015 (in thousands) Service cost $ 318 $ 336 $ 455 $ 397 Interest 340 394 334 341 Expected return on plan assets (694 ) (688 ) — — Recognized prior service cost (benefit) (26 ) (26 ) 29 29 Recognized net actuarial losses 200 204 200 149 Net periodic benefit (credit) cost $ 138 $ 220 $ 1,018 $ 916 Components of Net Periodic Benefit Cost (Credit) for the Six Months Ended June 30, Pension Benefits Supplemental Insurance/ 2016 2015 2016 2015 (in thousands) Service cost $ 636 $ 672 $ 910 $ 794 Interest 680 788 668 682 Expected return on plan assets (1,388 ) (1,376 ) — — Recognized prior service cost (benefit) (52 ) (52 ) 58 58 Recognized net actuarial losses 400 407 400 299 Net periodic benefit (credit) cost $ 276 $ 439 $ 2,036 $ 1,833 Contributions The company intends to contribute $2,075,000 to the Pension Plan in 2016. As of June 30, 2016, $1,575,000 has been contributed.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	Note 8. Fair Value Measurements The Company follows FASB ASC 820-10, Fair Value Measurements and Disclosures Level I – Quoted prices are available in active markets for identical assets or liabilities as of the reported date. The type of financial instruments included in Level I are highly liquid cash instruments with quoted prices such as G-7 government, agency securities, listed equities and money market securities, as well as listed derivative instruments. Level II – Pricing inputs are other than quoted prices in active markets, which are either directly or indirectly observable as of the reported date. The nature of these financial instruments include cash instruments for which quoted prices are available but traded less frequently, derivative instruments whose fair value have been derived using a model where inputs to the model are directly observable in the market, or can be derived principally from or corroborated by observable market data, and instruments that are fair valued using other financial instruments, the parameters of which can be directly observed. Instruments which are generally included in this category are corporate bonds and loans, mortgage whole loans and municipal bonds. Level III – Instruments that have little to no pricing observability as of the reported date. These financial instruments do not have two-way markets and are measured using management’s best estimate of fair value, where the inputs into the determination of fair value require significant management judgment or estimation. Instruments that are included in this category generally include certain commercial mortgage loans, certain private equity investments, and distressed debt and non-investment grade residual interests in securitizations. The results of the fair value hierarchy as of June 30, 2016, are as follows: Financial Instruments Measured at Fair Value on a Recurring Basis: Securities AFS Fair Value Measurements Using Carrying Quoted Prices Significant Significant (in thousands) U.S. Treasury $ 2,000 $ — $ 2,000 $ — U.S. Government Sponsored Enterprises 15,024 — 15,024 — SBA Backed Securities 45,705 — 45,705 — U.S. Government Agency and Sponsored Mortgage Backed Securities 280,877 — 280,877 — Privately Issued Residential Mortgage Backed Securities 1,286 — 1,286 — Obligations Issued by States and Political Subdivisions 212,838 — — 212,838 Other Debt Securities 4,942 — 4,942 — Equity Securities 261 261 — — Total $ 562,933 $ 261 $ 349,834 $ 212,838 Financial Instruments Measured at Fair Value on a Non-recurring Basis: Impaired Loans 259 — — 259 Impaired loan balances represent those collateral dependent loans where management has estimated the credit loss by comparing the loan’s carrying value against the expected realizable fair value of the collateral. Fair value is generally determined through a review process that includes independent appraisals, discounted cash flows, or other external assessments of the underlying collateral, which generally include various Level 3 inputs which are not identifiable. The Company discounts the fair values, as appropriate, based on management’s observations of the local real estate market for loans in this category. Appraisals, discounted cash flows and real estate tax assessments are reviewed quarterly. There is no specific policy regarding how frequently appraisals will be updated. Adjustments are made to appraisals and real estate tax assessments based on management’s estimate of changes in real estate values. Within the past twelve months there have been no updated appraisals, however, all impaired loans have been reviewed during the past quarter using either a discounted cash flow analysis, appraisal of collateral or other type of real estate tax assessment. The types of adjustments that are made to specific provisions (credits) relate to impaired loans recognized for the three and six month periods ended June 30, 2016 amounted to ($122,000) and ($136,000), respectively. There were no transfers between level 1, 2 and 3 for the six months ended June 30, 2016. There were no liabilities measured at fair value on a recurring or nonrecurring basis during the six month period ended June 30, 2016. The following table presents additional information about assets measured at fair value on a recurring and nonrecurring basis for which the Company has utilized Level 3 inputs to determine fair value (dollars in thousands). Management continues to monitor the assumptions used to value the assets listed below. Asset Fair Value Valuation Technique Unobservable Input Unobservable Input Securities AFS (4) $ 212,838 Discounted cash flow Discount rate 0%-1% (3) Impaired Loans $ 259 Appraisal of collateral (1) Appraisal adjustments (2) 0%-30% discount (1) Fair value is generally determined through independent appraisals of the underlying collateral, which generally include various Level 3 inputs which are not identifiable. (2) Appraisals may be adjusted by management for qualitative factors such as economic conditions and estimated expenses. (3) Weighted averages. (4) Municipal securities generally have maturities of one year or less and, therefore, the amortized cost equates to the fair value. The changes in Level 3 securities for the three month period ended June 30, 2016 are shown in the table below: Auction Rate Obligations Equity Total (in thousands) Balance at December 31, 2015 $ 3,820 $ 153,140 $ 37 $ 156,997 Purchases — 155,742 — 155,742 Maturities and calls — (100,245 ) (37 ) (100,282 ) Amortization — (97 ) — (97 ) Changes in fair value 478 — — 478 Balance at June 30, 2016 $ 4,298 $ 208,540 $ — $ 212,838 The amortized cost of Level 3 securities was $213,241,000 at June 30, 2016 with an unrealized loss of $403,000. The securities in this category are generally equity investments, municipal securities with no readily determinable fair value or failed auction rate securities. Management evaluated the fair value of these securities based on an evaluation of the underlying issuer, prevailing rates and market liquidity. The changes in Level 3 securities for the six month period ended June 30, 2015, are shown in the table below: Auction Rate Obligations Equity Total (in thousands) Balance at December 31, 2014 $ 3,820 $ 92,964 $ 102 $ 96,886 Purchases — 113,179 — 113,179 Maturities and calls — (57,411 ) (65 ) (57,476 ) Amortization — (11 ) — (11 ) Changes in fair value — — — — Balance at June 30, 2015 $ 3,820 $ 148,721 $ 37 $ 152,578 The amortized cost of Level 3 securities was $153,454,000 at June 30, 2015 with an unrealized loss of $876,000. The securities in this category are generally equity investments, municipal securities with no readily determinable fair value or failed auction rate securities. Management evaluated the fair value of these securities based on an evaluation of the underlying issuer, prevailing rates and market liquidity. The results of the fair value hierarchy as of December 31, 2015, are as follows: Financial Instruments Measured at Fair Value on a Recurring Basis: Securities AFS Fair Value Measurements Using Carrying Quoted Prices Significant Significant (in thousands) U.S. Treasury $ 1,989 $ — $ 1,989 $ — U.S. Government Sponsored Enterprises — — — — SBA Backed Securities 5,989 — 5,989 — U.S. Government Agency and Sponsored Mortgage Backed Securities 233,526 — 233,526 — Privately Issued Residential Mortgage Backed Securities 1,434 — 1,434 — Obligations Issued by States and Political Subdivisions 156,960 — — 156,960 Other Debt Securities 4,473 — 4,473 — Equity Securities 252 215 — 37 Total $ 404,623 $ 215 $ 247,411 $ 156,997 Financial Instruments Measured at Fair Value on a Non-recurring Basis: Impaired Loans $ 1,056 $ — $ — $ 1,056 Impaired loan balances represent those collateral dependent loans where management has estimated the credit loss by comparing the loan’s carrying value against the expected realizable fair value of the collateral. Fair value is generally determined through a review process that includes independent appraisals, discounted cash flows, or other external assessments of the underlying collateral, which generally include various Level 3 inputs which are not identifiable. The Company discounts the fair values, as appropriate, based on management’s observations of the local real estate market for loans in this category. Appraisals, discounted cash flows and real estate tax assessments are reviewed quarterly. There is no specific policy regarding how frequently appraisals will be updated. Adjustments are made to appraisals and real estate tax assessments based on management’s estimate of changes in real estate values. Within the past twelve months there have been no updated appraisals, however, all impaired loans have been reviewed during the past quarter using either a discounted cash flow analysis, appraisal of collateral or other type of real estate tax assessment. The types of adjustments that are made to specific provisions (credits) relate to impaired loans recognized for 2015 for the estimated credit loss amounted to a credit of $165,000. There were no transfers between level 1, 2 and 3 for the year ended December 31, 2015. There were no liabilities measured at fair value on a recurring or nonrecurring basis during the year ended December 31, 2015. The following table presents additional information about assets measured at fair value on a recurring and nonrecurring basis for which the Company has utilized Level 3 inputs to determine fair value (dollars in thousands). Management continues to monitor the assumptions used to value the assets listed below. Asset Fair Value Valuation Technique Unobservable Input Unobservable Input Securities AFS (4) $ 156,997 Discounted cash flow Discount rate 0%-1% (3) Impaired Loans $ 1,056 Appraisal of collateral (1) Appraisal adjustments (2) 0%-30% discount (1) Fair value is generally determined through independent appraisals of the underlying collateral, which generally include various Level 3 inputs which are not identifiable. (2) Appraisals may be adjusted by management for qualitative factors such as economic conditions and estimated expenses. (3) Weighted averages (4) Municipal securities generally have maturities of one year or less and, therefore, the amortized cost equates to the fair value.

Fair Values of Financial Instru

Fair Values of Financial Instruments	6 Months Ended
	Jun. 30, 2016
Investments, All Other Investments [Abstract]
Fair Values of Financial Instruments	Note 9. Fair Values of Financial Instruments The following methods and assumptions were used by the Company in estimating fair values of its financial instruments. Excluded from this disclosure are all nonfinancial instruments. Accordingly, the aggregate fair value amounts presented do not represent the underlying value of the Company. The assumptions used below are expected to approximate those that market participants would use in valuing these financial instruments. Fair value estimates are made at a specific point in time, based on available market information and judgments about the financial instrument, including estimates of timing, amount of expected future cash flows and the credit standing of the issuer. Such estimates do not consider the tax impact of the realization of unrealized gains or losses. In some cases, the fair value estimates cannot be substantiated by comparison to independent markets. In addition, the disclosed fair value may not be realized in the immediate settlement of the financial instrument. Care should be exercised in deriving conclusions about our business, its value or financial position based on the fair value information of financial instruments presented below. Securities held-to-maturity: The fair values of these securities were based on quoted market prices, where available, as provided by third-party investment portfolio pricing vendors. If quoted market prices were not available, fair values provided by the vendors were based on quoted market prices of comparable instruments in active markets and/or based on a matrix pricing methodology which employs The Bond Market Association’s standard calculations for cash flow and price/yield analysis, live benchmark bond pricing and terms/condition data available from major pricing sources. Management regards the inputs and methods used by third party pricing vendors to be “Level 2 inputs and methods” as defined in the “fair value hierarchy” provided by FASB. Loans Held-for-Sale: Fair value is measured using quoted market prices when available. These assets are typically categorized as Level 1. If quoted market prices are not available, comparable market values may be utilized. These assets are typically categorized as Level 2. Loans: For variable-rate loans, that reprice frequently and with no significant change in credit risk, fair values are based on carrying amounts. The fair value of other loans is estimated using discounted cash flow analysis, based on interest rates currently being offered for loans with similar terms to borrowers of similar credit quality. Incremental credit risk for nonperforming loans has been considered. Time deposits: The fair value of time deposits was estimated using a discounted cash flow approach that applies prevailing market interest rates for similar maturity instruments. The fair values of the Company’s time deposit liabilities do not take into consideration the value of the Company’s long-term relationships with depositors, which may have significant value. Other borrowed funds: The fair value of other borrowed funds is based on the discounted value of contractual cash flows. The discount rate used is estimated based on the rates currently offered for other borrowed funds of similar remaining maturities. Subordinated debentures: The fair value of subordinated debentures is based on the discounted value of contractual cash flows. The discount rate used is estimated based on the rates currently offered for other subordinated debentures of similar remaining maturities. The following presents (in thousands) the carrying amount, estimated fair value, and placement in the fair value hierarchy of the Company’s financial instruments as of June 30, 2016 and December 31, 2015. This table excludes financial instruments for which the carrying amount approximates fair value. Financial assets for which the fair value approximates carrying value include cash and cash equivalents, short-term investments, FHLBB stock and accrued interest receivable. Financial liabilities for which the fair value approximates carrying value include non-maturity deposits, short-term borrowings and accrued interest payable. Carrying Estimated Fair Value Level 2 Level 3 June 30, 2016 (in thousands) Financial assets: Securities held-to-maturity $ 1,573,829 $ 1,606,758 $ — $ 1,606,758 $ — Loans Held-for-Sale 12,403 12,704 — 12,704 — Loans (1) 1,778,041 1,808,359 — — 1,808,359 Financial liabilities: Time deposits 460,527 464,613 — 464,613 — Other borrowed funds 431,000 439,956 — 439,956 — Subordinated debentures 36,083 36,083 — — 36,083 December 31, 2015 Financial assets: Securities held-to-maturity $ 1,438,903 $ 1,438,960 $ — $ 1,438,960 $ — Loans (1) 1,708,461 1,677,270 — — 1,677,270 Financial liabilities: Time deposits 473,426 474,046 — 474,046 — Other borrowed funds 368,000 372,209 — 372,209 — Subordinated debentures 36,083 36,083 — — 36,083 (1) Comprised of loans (including collateral dependent impaired loans), net of deferred loan costs and the allowance for loan losses.

Recent Accounting Developments

Recent Accounting Developments	6 Months Ended
	Jun. 30, 2016
Accounting Changes and Error Corrections [Abstract]
Recent Accounting Developments	Note 10. Recent Accounting Developments In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers (Topic 606). This ASU is intended to create a single source of revenue guidance which is more principles based than current revenue guidance. The guidance affects any entity that either enters into contracts with customers to transfer goods or services, or enters into contracts for the transfer of non-financial assets, unless those contracts are within the scope of other standards. In August 2015, the FASB issued ASU 2015-14, “Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date” to amend the effective date of ASU 2014-09. The amendments in ASU 2014-09 are effective for annual and interim periods within fiscal years beginning after December 15, 2017. Earlier adoption is permitted only as of annual reporting periods beginning after December 15, 2016, including interim reporting periods within that reporting period. The FASB has since issued additional related ASUs amendments intended to clarify certain aspects and improve understanding of the implementation guidance of Topic 606 but do not change the core principles of the guidance in Topic 606. The effective date and transition requirements for the amendments are the same as the effective date and transition requirements of Topic 606. The Company is currently evaluating the potential impact of the ASU and its amendments on the Company’s financial statements and results of operations. In January 2016, FASB issued ASU 2016-1, “Financial Instruments-Overall” (Subtopic 825-10) Recognition and Measurement of Financial Assets and Financial Liabilities In February 2016, the FASB issued ASU 2016-02, Leases. In March 2016, the FASB issued ASU 2016-07, Investments—Equity Method and Joint Ventures Simplifying the Transition to the Equity Method of Accounting In March 2016, the FASB issued ASU 2016-09, Compensation—Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting. In June 2016, the FASB issued ASU 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments.

Securities Available-for-Sale (

Securities Available-for-Sale (Tables)	6 Months Ended
	Jun. 30, 2016
Text Block [Abstract]
Summary of Securities Available-for-Sale	June 30, 2016 December 31, 2015 Amortized Gross Gross Fair Amortized Gross Gross Fair (in thousands) U.S. Treasury $ 1,999 $ 1 $ — $ 2,000 $ 1,999 $ — $ 10 $ 1,989 U.S. Government Sponsored Enterprises 15,000 24 — 15,024 — — — — SBA Backed Securities 45,698 31 24 45,705 5,983 8 2 5,989 U.S. Government Agency and Sponsored Enterprise Mortgage-Backed Securities 280,931 434 488 280,877 232,967 859 300 233,526 Privately Issued Residential Mortgage-Backed Securities 1,301 2 17 1,286 1,437 10 13 1,434 Obligations Issued by States and Political Subdivisions 213,241 — 403 212,838 157,838 — 878 156,960 Other Debt Securities 5,100 — 158 4,942 4,600 3 130 4,473 Equity Securities 116 145 — 261 153 99 — 252 Total $ 563,386 $ 637 $ 1,090 $ 562,933 $ 404,977 $ 979 $ 1,333 $ 404,623
Maturity Distribution of Securities Available-for-Sale	The following table shows the maturity distribution of the Company’s securities available-for-sale at June 30, 2016. Amortized Fair (in thousands) Within one year $ 217,903 $ 217,912 After one but within five years 232,419 232,311 After five but within ten years 105,748 105,767 More than 10 years 5,700 5,292 Non-maturing 1,616 1,651 Total $ 563,386 $ 562,933
Continuous Unrealized Loss Position for Less than 12 Months and 12 Months or Longer	The following table shows the temporarily impaired securities of the Company’s available-for-sale portfolio at June 30, 2016. This table shows the unrealized market loss of securities that have been in a continuous unrealized loss position for less than 12 months and a continuous loss position for 12 months or longer. There are 37 and 10 securities that are temporarily impaired for less than 12 months and for 12 months or longer, respectively, out of a total of 327 holdings at June 30, 2016. June 30, 2016 Less than 12 months 12 months or longer Total Temporarily Impaired Investments Fair Unrealized Fair Unrealized Fair Unrealized (in thousands) U.S. Treasury $ — $ — $ — $ — $ — $ — SBA Backed Securities 10,959 24 — — 10,959 24 U.S. Government Agency and Sponsored Enterprise Mortgage-Backed Securities 127,281 372 27,894 116 155,175 488 Privately Issued Residential Mortgage-Backed Securities 415 2 467 15 882 17 Obligations Issued by States and Political Subdivisions — — 4,298 403 4,298 403 Other Debt Securities 1,553 47 1,789 111 3,342 158 Total temporarily impaired securities $ 140,208 $ 445 $ 34,448 $ 645 $ 174,656 $ 1,090 The following table shows the temporarily impaired securities of the Company’s available-for-sale portfolio at December 31, 2015. This table shows the unrealized market loss of securities that have been in a continuous unrealized loss position for less than 12 months and a continuous loss position for 12 months or longer. There are 14 and 11 securities that are temporarily impaired for less than 12 months and for 12 months or longer, respectively, out of a total of 290 holdings at December 31, 2015. December 31, 2015 Less than 12 months 12 months or longer Total Temporarily Impaired Investments Fair Unrealized Fair Unrealized Fair Unrealized (in thousands) U.S. Treasury $ 1,989 $ 10 $ — $ — $ 1,989 $ 10 SBA Backed Securities 1,031 2 — — 1,031 2 U.S. Government Agency and Sponsored Enterprise Mortgage-Backed Securities 26,519 52 49,341 248 75,860 300 Privately Issued Residential Mortgage-Backed Securities — — 490 13 490 13 Obligations Issued by States and Political Subdivisions — — 3,820 878 3,820 878 Other Debt Securities 497 3 1,373 127 1,870 130 Total temporarily impaired securities $ 30,036 $ 67 $ 55,024 $ 1,266 $ 85,060 $ 1,333

Investment Securities Held-to20

Investment Securities Held-to-Maturity (Tables)	6 Months Ended
	Jun. 30, 2016
Text Block [Abstract]
Summary of Held-to-Maturity Securities	June 30, 2016 December 31, 2015 Amortized Gross Gross Estimated Amortized Gross Gross Estimated (in thousands) U.S. Government Sponsored Enterprises $ 190,026 $ 3,240 $ 1 $ 193,265 $ 186,734 $ 2,234 $ 141 $ 188,827 SBA Backed Securities 20,987 155 — 21,142 — — — — U.S. Government Agency and Sponsored Enterprises Mortgage-Backed Securities 1,362,816 30,164 629 1,392,351 1,252,169 7,547 9,583 1,250,133 Total $ 1,573,829 $ 33,559 $ 630 $ 1,606,758 $ 1,438,903 $ 9,781 $ 9,724 $ 1,438,960
Company's Securities Held-to-Maturity	The following table shows the maturity distribution of the Company’s securities held-to-maturity at June 30, 2016. Amortized Fair (in thousands) Within one year $ 10,047 $ 10,137 After one but within five years 1,400,716 1,427,594 After five but within ten years 159,917 165,817 More than ten years 3,149 3,210 Total $ 1,573,829 $ 1,606,758
Unrealized Market Loss of Securities	The following table shows the temporarily impaired securities of the Company’s held-to-maturity portfolio at June 30, 2016. This table shows the unrealized market loss of securities that have been in a continuous unrealized loss position for 12 months or less and a continuous loss position for 12 months or longer. There are 6 and 16 securities that are temporarily impaired for less than 12 months and for 12 months or longer, respectively, out of a total of 352 holdings at June 30, 2016. June 30, 2016 Less Than 12 Months 12 Months or Longer Total Temporarily Impaired Investments Fair Unrealized Fair Unrealized Fair Unrealized (in thousands) U.S. Government Sponsored Enterprises $ 14,999 $ 1 $ — $ — $ 14,999 $ 1 U.S. Government Agency and Sponsored Enterprise Mortgage-Backed Securities 23,087 93 70,461 536 93,548 629 Total temporarily impaired securities $ 38,086 $ 94 $ 70,461 $ 536 $ 108,547 $ 630 The following table shows the temporarily impaired securities of the Company’s held-to-maturity portfolio at December 31, 2015. This table shows the unrealized market loss of securities that have been in a continuous unrealized loss position for less than 12 months and a continuous loss position for 12 months or longer. There are 101 and 26 securities that are temporarily impaired for less than 12 months and for 12 months or longer, respectively, out of a total of 322 holdings at December 31, 2015. December 31, 2015 Less Than 12 Months 12 Months or Longer Total Temporarily Impaired Investments Fair Unrealized Fair Unrealized Fair Unrealized (in thousands) U.S. Government Sponsored Enterprises $ 9,859 $ 141 $ — $ — $ 9,859 $ 141 U.S. Government Agency and Sponsored Enterprise Mortgage-Backed Securities 626,218 6,657 123,864 2,926 750,082 9,583 Total temporarily impaired securities $ 636,077 $ 6,798 $ 123,864 $ 2,926 $ 759,941 $ 9,724

Allowance for Loan Losses (Tabl

Allowance for Loan Losses (Tables)	6 Months Ended
	Jun. 30, 2016
Receivables [Abstract]
Summary of Changes in Allowance for Loan Losses	The following table summarizes the changes in the Company’s allowance for loan losses for the periods indicated. Three months ended Six months ended 2016 2015 2016 2015 (in thousands) Allowance for loan losses, beginning of period $ 23,544 $ 22,529 $ 23,075 $ 22,318 Loans charged off (111 ) (403 ) (180 ) (484 ) Recoveries on loans previously charged-off 164 119 252 211 Net recoveries (charge-offs) 53 (284 ) 72 (273 ) Provision charged to expense 350 — 800 200 Reclassification to other liabilities* (84 ) — (84 ) — Allowance for loan losses, end of period $ 23,863 $ 22,245 $ 23,863 $ 22,245 * The reclassification relates to allowance for loan losses allocations on unused commitments that have been reclassified to other liabilities.
Summary of Allowance for Loan Losses	The following table summarizes the changes in the Company’s allowance for loan losses for the periods indicated. Three months ended Six months ended 2016 2015 2016 2015 (in thousands) Allowance for loan losses, beginning of period $ 23,544 $ 22,529 $ 23,075 $ 22,318 Loans charged off (111 ) (403 ) (180 ) (484 ) Recoveries on loans previously charged-off 164 119 252 211 Net recoveries (charge-offs) 53 (284 ) 72 (273 ) Provision charged to expense 350 — 800 200 Reclassification to other liabilities* (84 ) — (84 ) — Allowance for loan losses, end of period $ 23,863 $ 22,245 $ 23,863 $ 22,245 * The reclassification relates to allowance for loan losses allocations on unused commitments that have been reclassified to other liabilities. Further information pertaining to the allowance for loan losses for the three months ending June 30, 2016 follows: Construction Commercial Municipal Commercial Residential Consumer Home Unallocated Total (in thousands) Allowance for loan losses: Balance at March 31, 2016 $ 1,973 $ 6,693 $ 990 $ 10,533 $ 1,249 $ 693 $ 1,185 $ 228 $ 23,544 Charge-offs — — — — — (111 ) — — (111 ) Recoveries — 56 — — 2 106 — — 164 Provision 264 (878 ) 811 128 53 (77 ) 9 40 350 Reclassification to other liabilities (3 ) (29 ) — (11 ) (2 ) (3 ) (36 ) — (84 ) Ending balance at June 30, 2016 $ 2,234 $ 5,842 $ 1,801 $ 10,650 $ 1,302 $ 608 $ 1,158 $ 268 $ 23,863 Amount of allowance for loan losses for loans deemed to be impaired $ 6 $ 10 $ — $ 151 $ 7 $ — $ — $ — $ 174 Amount of allowance for loan losses for loans not deemed to be impaired $ 2,228 $ 5,832 $ 1,801 $ 10,499 $ 1,295 $ 608 $ 1,158 $ 268 $ 23,689 Loans: Ending balance $ 31,178 $ 493,033 $ 134,386 $ 728,658 $ 219,494 $ 11,339 $ 183,816 $ — $ 1,801,904 Loans deemed to be impaired $ 96 $ 410 $ — $ 3,736 $ 215 $ — $ — $ — $ 4,457 Loans not deemed to be impaired $ 31,082 $ 492,623 $ 134,386 $ 724,922 $ 219,279 $ 11,339 $ 183,816 $ — $ 1,797,447 Further information pertaining to the allowance for loan losses for the six months ending June 30, 2016 follows: Construction and Land Commercial and Municipal Commercial Residential Consumer Home Unallocated Total (in thousands) Allowance for loan losses: Balance at December 31, 2015 $ 2,041 $ 5,899 $ 994 $ 10,589 $ 1,320 $ 644 $ 1,077 $ 511 $ 23,075 Charge-offs — — — — — (180 ) — — (180 ) Recoveries — 91 — — 3 158 — — 252 Provision 196 (119 ) 807 72 (19 ) (11 ) 117 (243 ) 800 Reclassification to other liabilities (3 ) (29 ) — (11 ) (2 ) (3 ) (36 ) — (84 ) Ending balance at June 30, 2016 $ 2,234 $ 5,842 $ 1,801 $ 10,650 $ 1,302 $ 608 $ 1,158 $ 268 $ 23,863 Amount of allowance for loan losses for loans deemed to be impaired $ 6 $ 10 $ — $ 151 $ 7 $ — $ — $ — $ 174 Amount of allowance for loan losses for loans not deemed to be impaired $ 2,228 $ 5,832 $ 1,801 $ 10,499 $ 1,295 $ 608 $ 1,158 $ 268 $ 23,689 Loans: Ending balance $ 31,178 $ 493,033 $ 134,386 $ 728,658 $ 219,494 $ 11,339 $ 183,816 $ — $ 1,801,904 Loans deemed to be impaired $ 96 $ 410 $ — $ 3,736 $ 215 $ — $ — $ — $ 4,457 Loans not deemed to be impaired $ 31,082 $ 492,623 $ 134,386 $ 724,922 $ 219,279 $ 11,339 $ 183,816 $ — $ 1,797,447 Further information pertaining to the allowance for loan losses for the three months ending June 30, 2015 follows: Construction and Land Commercial and Municipal Commercial Residential Consumer Home Unallocated Total (in thousands) Allowance for loan losses: Balance at March 31, 2015 $ 1,884 $ 4,645 $ 1,373 $ 11,127 $ 799 $ 714 $ 614 $ 1,373 $ 22,529 Charge-offs — (52 ) — (298 ) — (53 ) — — (403 ) Recoveries — 56 — 2 2 59 — — 119 Provision (151 ) (221 ) (373 ) 892 (79 ) (11 ) 36 (93 ) — Ending balance at June 30, 2015 $ 1,733 $ 4,428 $ 1,000 $ 11,723 $ 722 $ 709 $ 650 $ 1,280 $ 22,245 Amount of allowance for loan losses for loans deemed to be impaired $ 12 $ 43 $ — $ 108 $ 41 $ — $ 91 $ — $ 295 Amount of allowance for loan losses for loans not deemed to be impaired $ 1,721 $ 4,385 $ 1,000 $ 11,615 $ 681 $ 709 $ 559 $ 1,280 $ 21,950 Loans: Ending balance $ 26,521 $ 291,142 $ 87,241 $ 713,770 $ 248,103 $ 10,646 $ 167,271 $ — $ 1,544,694 Loans deemed to be impaired $ 101 $ 595 $ — $ 1,705 $ 941 $ — $ 91 $ — $ 3,433 Loans not deemed to be impaired $ 26,420 $ 290,547 $ 87,241 $ 712,065 $ 247,162 $ 10,646 $ 167,180 $ — $ 1,541,261 Further information pertaining to the allowance for loan losses for the six months ending June 30, 2015 follows: Construction and Land Commercial and Municipal Commercial Residential Consumer Home Unallocated Total (in thousands) Allowance for loan losses: Balance at December 31, 2104 $ 1,592 $ 4,758 $ 1,488 $ 11,199 $ 775 $ 810 $ 599 $ 1,097 $ 22,318 Charge-offs — (52 ) — (298 ) — (134 ) — — (484 ) Recoveries — 71 — 4 4 132 — — 211 Provision 141 (349 ) (488 ) 818 (57 ) (99 ) 51 183 200 Ending balance at June 30, 2015 $ 1,733 $ 4,428 $ 1,000 $ 11,723 $ 722 $ 709 $ 650 $ 1,280 $ 22,245 Amount of allowance for loan losses for loans deemed to be impaired $ 12 $ 43 $ — $ 108 $ 41 $ — $ 91 $ — $ 295 Amount of allowance for loan losses for loans not deemed to be impaired $ 1,721 $ 4,385 $ 1,000 $ 11,615 $ 681 $ 709 $ 559 $ 1,280 $ 21,950 Loans: Ending balance $ 26,521 $ 291,142 $ 87,241 $ 713,770 $ 248,103 $ 10,646 $ 167,271 $ — $ 1,544,694 Loans deemed to be impaired $ 101 $ 595 $ — $ 1,705 $ 941 $ — $ 91 $ — $ 3,433 Loans not deemed to be impaired $ 26,420 $ 290,547 $ 87,241 $ 712,065 $ 247,162 $ 10,646 $ 167,180 $ — $ 1,541,261
Loans by Risk Rating	The following table presents the Company’s loans by risk rating at June 30, 2016. Construction Commercial Municipal Commercial (in thousands) Grade: 1-3 (Pass) $ 24,048 $ 492,623 $ 134,386 $ 724,735 4 (Monitor) 7,034 — — 187 5 (Substandard) — — — — 6 (Doubtful) — — — — Impaired 96 410 — 3,736 Total $ 31,178 $ 493,033 $ 134,386 $ 728,658 The following table presents the Company’s loans by risk rating at December 31, 2015. Construction Commercial Municipal Commercial (in thousands) Grade: 1-3 (Pass) $ 20,281 $ 451,774 $ 85,685 $ 718,911 4 (Monitor) 7,042 18 — 917 5 (Substandard) — — — — 6 (Doubtful) — — — — Impaired 98 443 — 1,678 Total $ 27,421 $ 452,235 $ 85,685 $ 721,506
Loans by Credit Ratings Issued by National Organizations	Credit ratings issued by national organizations were utilized as credit quality indicators as presented in the following table at June 30, 2016. Commercial Municipal Commercial Total (in thousands) Credit Rating: Aaa – Aa3 $ 282,048 $ 68,806 $ 7,074 $ 357,928 A1 – A3 140,324 7,400 130,152 277,876 Baa1 – Baa3 — 53,520 166,105 219,625 Ba2 — 3,610 — 3,610 Total $ 422,372 $ 133,336 $ 303,331 $ 859,039 Credit ratings issued by national organizations were utilized as credit quality indicators as presented in the following table at December 31, 2015. Commercial Municipal Commercial Total (in thousands) Credit Rating: Aaa – Aa3 $ 234,733 $ 63,865 $ 7,547 $ 306,145 A1 – A3 140,419 7,400 130,872 278,691 Baa1 – Baa3 — 8,890 167,489 176,379 Ba2 — 4,480 — 4,480 Total $ 375,152 $ 84,635 $ 305,908 $ 765,695
Aging of Past Due Loan Losses	Further information pertaining to the allowance for loan losses at June 30, 2016 follows: Accruing 30-89 Days Non Accruing Total Current Total (in thousands) Construction and land development $ — $ 96 $ — $ 96 $ 31,082 $ 31,178 Commercial and industrial 470 52 — 522 492,511 493,033 Municipal — — — — 134,386 134,386 Commercial real estate 1,080 162 — 1,242 727,416 728,658 Residential real estate 736 844 — 1,580 217,914 219,494 Consumer and overdrafts 1 3 — 4 11,335 11,339 Home equity 359 329 — 688 183,128 183,816 Total $ 2,646 $ 1,486 $ — $ 4,132 $ 1,797,772 $ 1,801,904 Further information pertaining to the allowance for loan losses at December 31, 2015 follows: Accruing 30-89 Days Non Accruing Total Current Total (in thousands) Construction and land development $ — $ 99 $ — $ 99 $ 27,322 $ 27,421 Commercial and industrial — 60 — 60 452,175 452,235 Municipal — — — — 85,685 85,685 Commercial real estate 1,462 174 — 1,636 719,870 721,506 Residential real estate 596 1,559 — 2,155 253,191 255,346 Consumer and overdrafts 6 — — 6 11,317 11,323 Home equity 628 444 — 1,072 176,948 178,020 Total $ 2,692 $ 2,336 $ — $ 5,028 $ 1,726,508 $ 1,731,536
Information Pertaining to Impaired Loans	The following is information pertaining to impaired loans for June 30, 2016: Carrying Unpaid Required Average Interest Average Interest (in thousands) With no required reserve recorded: Construction and land development $ — $ — $ — $ — $ — $ — $ — Commercial and industrial 52 239 — 54 — 56 — Municipal — — — — — — — Commercial real estate 596 596 — 329 16 188 22 Residential real estate 103 190 — 106 2 108 4 Consumer — — — — — — — Home equity — — — — — — — Total $ 751 $ 1,025 $ — $ 489 $ 18 $ 352 $ 26 With required reserve recorded: Construction and land development $ 96 $ 108 $ 6 $ 97 $ — $ 97 $ — Commercial and industrial 358 373 10 370 5 374 9 Municipal — — — — — — — Commercial real estate 3,140 3,239 151 2,030 20 1,878 33 Residential real estate 112 112 7 283 1 505 3 Consumer — — — — — — — Home equity — — — 22 — 51 — Total $ 3,706 $ 3,832 $ 174 $ 2,802 $ 26 $ 2,905 $ 45 Total: Construction and land development $ 96 $ 108 $ 6 $ 97 $ — $ 97 $ — Commercial and industrial 410 612 10 424 5 430 9 Municipal — — — — — — — Commercial real estate 3,736 3,835 151 2,359 36 2,066 55 Residential real estate 215 302 7 389 3 613 7 Consumer — — — — — — — Home equity — — — 22 — 51 — Total $ 4,457 $ 4,857 $ 174 $ 3,291 $ 44 $ 3,257 $ 71 The following is information pertaining to impaired loans for June 30, 2015: Carrying Unpaid Required Average Interest Average Interest (in thousands) With no required reserve recorded: Construction and land development $ — $ — $ — $ — $ — $ — $ — Commercial and industrial 32 32 — 47 — 40 — Municipal — — — — — — — Commercial real estate — — — 196 — 280 — Residential real estate 126 210 — 129 2 131 4 Consumer — — — — — — — Home equity — — — — — — — Total $ 158 $ 242 $ — $ 372 $ 2 $ 451 $ 4 With required reserve recorded: Construction and land development $ 101 $ 108 $ 12 $ 102 $ — $ 102 $ — Commercial and industrial 563 765 43 644 5 722 11 Municipal — — — — — — — Commercial real estate 1,705 1,801 108 2,809 17 3,286 33 Residential real estate 815 815 41 817 1 820 7 Consumer — — — — — — — Home equity 91 91 91 91 — 92 — Total $ 3,275 $ 3,580 $ 295 $ 4,463 $ 23 $ 5,022 $ 51 Total: Construction and land development $ 101 $ 108 $ 12 $ 102 $ — $ 102 $ — Commercial and industrial 595 797 43 691 5 762 11 Municipal — — — — — — — Commercial real estate 1,705 1,801 108 3,005 17 3,566 33 Residential real estate 941 1,025 41 946 3 951 11 Consumer — — — — — — — Home equity 91 91 91 91 — 92 — Total $ 3,433 $ 3,822 $ 295 $ 4,835 $ 25 $ 5,473 $ 55

Reclassifications Out of Accu22

Reclassifications Out of Accumulated Other Comprehensive Income (Tables)	6 Months Ended
	Jun. 30, 2016
Text Block [Abstract]
Reclassifications Out of Accumulated Other Comprehensive Income	Amount Reclassified from Accumulated Other Comprehensive Income Details about Accumulated Other Comprehensive Income Components Three Three Affected Line Item in the Statement where Net Income is Presented (in thousands) Unrealized gains and losses on available-for-sale securities $ 45 $ 118 Net gains on sales of investments Tax (expense) or benefit (18 ) (47 ) Provision for income taxes Net of tax $ 27 $ 71 Net income Accretion of unrealized losses transferred $ (1,170 ) $ (1,576 ) Interest on securities held-to-maturity Tax (expense) or benefit 408 549 Provision for income taxes Net of tax $ (762 ) $ (1,027 ) Net income Amortization of defined benefit pension items Prior-service costs $ (3 )(b) $ (3 )(b) Salaries and employee benefits Actuarial gains (losses) (401 )(b) (352 )(b) Salaries and employee benefits Total before tax (404 ) (355 ) Income before taxes Tax (expense) or benefit 161 142 Provision for income taxes Net of tax $ (243 ) $ (213 ) Net income Total reclassifications for the period $ (978 ) $ (1,169 ) Net income Details about Accumulated Other Comprehensive Income Components Six Six Affected Line Item in the Statement where Net Income is Presented (in thousands) Unrealized gains and losses on available-for-sale securities $ 45 $ 118 Net gains on sales of investments Tax (expense) or benefit (18 ) (47 ) Provision for income taxes Net of tax $ 27 $ 71 Net income Accretion of unrealized losses transferred $ (2,682 ) $ (2,705 ) Interest on securities held-to-maturity Tax (expense) or benefit 935 943 Provision for income taxes Net of tax $ (1,747 ) $ (1,762 ) Net income Amortization of defined benefit pension items Prior-service costs $ (5 )(b) $ (6 )(b) Salaries and employee benefits Actuarial gains (losses) (802 )(b) (704 )(b) Salaries and employee benefits Total before tax (807 ) (710 ) Income before taxes Tax (expense) or benefit 322 284 Provision for income taxes Net of tax $ (485 ) $ (426 ) Net income Total reclassifications for the period $ (2,205 ) $ (2,117 ) Net income, net of tax (a) Amount in parentheses indicates reductions to net income. (b) These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see Employee Benefits footnote (Note 7) for additional details).

Earnings per Share ("EPS") (Tab

Earnings per Share ("EPS") (Tables)	6 Months Ended
	Jun. 30, 2016
Earnings Per Share [Abstract]
Reconciliation of Basic EPS and Diluted EPS	The following table is a reconciliation of basic EPS and diluted EPS. Three Months Ended Six Months Ended (in thousands except share and per share data) 2016 2015 2016 2015 Basic EPS Computation: Numerator: Net income, Class A $ 4,902 $ 4,654 $ 9,071 $ 8,549 Net income, Class B 1,339 1,271 2,478 2,335 Denominator: Weighted average shares outstanding, Class A 3,600,729 3,600,729 3,600,729 3,600,729 Weighted average shares outstanding, Class B 1,967,180 1,967,180 1,967,180 1,967,180 Basic EPS, Class A $ 1.36 $ 1.29 $ 2.52 $ 2.37 Basic EPS, Class B 0.68 0.65 1.26 1.19 Diluted EPS Computation: Numerator: Net income, Class A $ 4,902 $ 4,654 $ 9,071 $ 8,549 Net income, Class B 1,339 1,271 2,478 2,335 Total net income, for diluted EPS, Class A computation 6,241 5,925 11,549 10,884 Denominator: Weighted average shares outstanding, basic, Class A 3,600,729 3,600,729 3,600,729 3,600,729 Weighted average shares outstanding, Class B 1,967,180 1,967,180 1,967,180 1,967,180 Weighted average shares outstanding diluted, Class A 5,567,909 5,567,909 5,567,909 5,567,909 Weighted average shares outstanding, Class B 1,967,180 1,967,180 1,967,180 1,967,180 Diluted EPS, Class A $ 1.12 $ 1.06 $ 2.07 $ 1.95 Diluted EPS, Class B 0.68 0.65 1.26 1.19

Employee Benefits (Tables)

Employee Benefits (Tables)	6 Months Ended
	Jun. 30, 2016
Compensation and Retirement Disclosure [Abstract]
Components of Net Periodic Benefit Cost (Credit)	Components of Net Periodic Benefit Cost (Credit) for the Three Months Ended June 30, Pension Benefits Supplemental Insurance/ 2016 2015 2016 2015 (in thousands) Service cost $ 318 $ 336 $ 455 $ 397 Interest 340 394 334 341 Expected return on plan assets (694 ) (688 ) — — Recognized prior service cost (benefit) (26 ) (26 ) 29 29 Recognized net actuarial losses 200 204 200 149 Net periodic benefit (credit) cost $ 138 $ 220 $ 1,018 $ 916 Components of Net Periodic Benefit Cost (Credit) for the Six Months Ended June 30, Pension Benefits Supplemental Insurance/ 2016 2015 2016 2015 (in thousands) Service cost $ 636 $ 672 $ 910 $ 794 Interest 680 788 668 682 Expected return on plan assets (1,388 ) (1,376 ) — — Recognized prior service cost (benefit) (52 ) (52 ) 58 58 Recognized net actuarial losses 400 407 400 299 Net periodic benefit (credit) cost $ 276 $ 439 $ 2,036 $ 1,833

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2016
Fair Value Disclosures [Abstract]
Financial Instruments Measured at Fair Value on a Recurring and Non-recurring Basis	The results of the fair value hierarchy as of June 30, 2016, are as follows: Financial Instruments Measured at Fair Value on a Recurring Basis: Securities AFS Fair Value Measurements Using Carrying Quoted Prices Significant Significant (in thousands) U.S. Treasury $ 2,000 $ 0 $ 2,000 $ 0 U.S. Government Sponsored Enterprises 15,024 0 15,024 0 SBA Backed Securities 45,705 0 45,705 0 U.S. Government Agency and Sponsored Mortgage Backed Securities 280,877 0 280,877 0 Privately Issued Residential Mortgage Backed Securities 1,286 0 1,286 0 Obligations Issued by States and Political Subdivisions 212,838 0 0 212,838 Other Debt Securities 4,942 0 4,942 0 Equity Securities 261 261 0 0 Total $ 562,933 $ 261 $ 349,834 $ 212,838 Financial Instruments Measured at Fair Value on a Non-recurring Basis: Impaired Loans 259 0 0 259 The results of the fair value hierarchy as of December 31, 2015, are as follows: Financial Instruments Measured at Fair Value on a Recurring Basis: Securities AFS Fair Value Measurements Using Carrying Quoted Prices Significant Significant (in thousands) U.S. Treasury $ 1,989 $ — $ 1,989 $ — U.S. Government Sponsored Enterprises — — — — SBA Backed Securities 5,989 — 5,989 — U.S. Government Agency and Sponsored Mortgage Backed Securities 233,526 — 233,526 — Privately Issued Residential Mortgage Backed Securities 1,434 — 1,434 — Obligations Issued by States and Political Subdivisions 156,960 — — 156,960 Other Debt Securities 4,473 — 4,473 — Equity Securities 252 215 — 37 Total $ 404,623 $ 215 $ 247,411 $ 156,997 Financial Instruments Measured at Fair Value on a Non-recurring Basis: Impaired Loans $ 1,056 $ — $ — $ 1,056
Assets Measured at Fair Value	The following table presents additional information about assets measured at fair value on a recurring and nonrecurring basis for which the Company has utilized Level 3 inputs to determine fair value (dollars in thousands). Management continues to monitor the assumptions used to value the assets listed below. Asset Fair Value Valuation Technique Unobservable Input Unobservable Input Securities AFS (4) $ 212,838 Discounted cash flow Discount rate 0%-1% (3) Impaired Loans $ 259 Appraisal of collateral (1) Appraisal adjustments (2) 0%-30% discount (1) Fair value is generally determined through independent appraisals of the underlying collateral, which generally include various Level 3 inputs which are not identifiable. (2) Appraisals may be adjusted by management for qualitative factors such as economic conditions and estimated expenses. (3) Weighted averages. (4) Municipal securities generally have maturities of one year or less and, therefore, the amortized cost equates to the fair value. The following table presents additional information about assets measured at fair value on a recurring and nonrecurring basis for which the Company has utilized Level 3 inputs to determine fair value (dollars in thousands). Management continues to monitor the assumptions used to value the assets listed below. Asset Fair Value Valuation Technique Unobservable Input Unobservable Input Securities AFS (4) $ 156,997 Discounted cash flow Discount rate 0%-1% (3) Impaired Loans $ 1,056 Appraisal of collateral (1) Appraisal adjustments (2) 0%-30% discount (1) Fair value is generally determined through independent appraisals of the underlying collateral, which generally include various Level 3 inputs which are not identifiable. (2) Appraisals may be adjusted by management for qualitative factors such as economic conditions and estimated expenses. (3) Weighted averages (4) Municipal securities generally have maturities of one year or less and, therefore, the amortized cost equates to the fair value.
Changes in Level 3 Securities	The changes in Level 3 securities for the three month period ended June 30, 2016 are shown in the table below: Auction Rate Obligations Equity Total (in thousands) Balance at December 31, 2015 $ 3,820 $ 153,140 $ 37 $ 156,997 Purchases — 155,742 — 155,742 Maturities and calls — (100,245 ) (37 ) (100,282 ) Amortization — (97 ) — (97 ) Changes in fair value 478 — — 478 Balance at June 30, 2016 $ 4,298 $ 208,540 $ — $ 212,838 The changes in Level 3 securities for the six month period ended June 30, 2015, are shown in the table below: Auction Rate Obligations Equity Total (in thousands) Balance at December 31, 2014 $ 3,820 $ 92,964 $ 102 $ 96,886 Purchases — 113,179 — 113,179 Maturities and calls — (57,411 ) (65 ) (57,476 ) Amortization — (11 ) — (11 ) Changes in fair value — — — — Balance at June 30, 2015 $ 3,820 $ 148,721 $ 37 $ 152,578

Fair Values of Financial Inst26

Fair Values of Financial Instruments (Tables)	6 Months Ended
	Jun. 30, 2016
Investments, All Other Investments [Abstract]
Carrying Amounts and Fair Values of Company's Financial Instruments	The following presents (in thousands) the carrying amount, estimated fair value, and placement in the fair value hierarchy of the Company’s financial instruments as of June 30, 2016 and December 31, 2015. This table excludes financial instruments for which the carrying amount approximates fair value. Financial assets for which the fair value approximates carrying value include cash and cash equivalents, short-term investments, FHLBB stock and accrued interest receivable. Financial liabilities for which the fair value approximates carrying value include non-maturity deposits, short-term borrowings and accrued interest payable. Carrying Estimated Fair Value Level 2 Level 3 June 30, 2016 (in thousands) Financial assets: Securities held-to-maturity $ 1,573,829 $ 1,606,758 $ — $ 1,606,758 $ — Loans Held-for-Sale 12,403 12,704 — 12,704 — Loans (1) 1,778,041 1,808,359 — — 1,808,359 Financial liabilities: Time deposits 460,527 464,613 — 464,613 — Other borrowed funds 431,000 439,956 — 439,956 — Subordinated debentures 36,083 36,083 — — 36,083 December 31, 2015 Financial assets: Securities held-to-maturity $ 1,438,903 $ 1,438,960 $ — $ 1,438,960 $ — Loans (1) 1,708,461 1,677,270 — — 1,677,270 Financial liabilities: Time deposits 473,426 474,046 — 474,046 — Other borrowed funds 368,000 372,209 — 372,209 — Subordinated debentures 36,083 36,083 — — 36,083 (1) Comprised of loans (including collateral dependent impaired loans), net of deferred loan costs and the allowance for loan losses.

Basis of Financial Statement 27

Basis of Financial Statement Presentation - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2016Segment
Basis Of Presentation [Line Items]
Number of reportable segments	1
Century Bancorp Capital Trust II [Member]
Basis Of Presentation [Line Items]
Equity ownership interest	100.00%

Securities Available-for-Sale -

Securities Available-for-Sale - Summary of Securities Available-for-Sale (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 563,386	$ 404,977
Gross Unrealized Gains	637	979
Gross Unrealized Losses	1,090	1,333
Total, Fair Value	562,933	404,623
U.S. Treasury [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,999	1,999
Gross Unrealized Gains	1
Gross Unrealized Losses		10
Total, Fair Value	2,000	1,989
U.S. Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	15,000
Gross Unrealized Gains	24
Total, Fair Value	15,024
SBA Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	45,698	5,983
Gross Unrealized Gains	31	8
Gross Unrealized Losses	24	2
Total, Fair Value	45,705	5,989
U.S. Government Agency and Sponsored Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	280,931	232,967
Gross Unrealized Gains	434	859
Gross Unrealized Losses	488	300
Total, Fair Value	280,877	233,526
Privately Issued Residential Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,301	1,437
Gross Unrealized Gains	2	10
Gross Unrealized Losses	17	13
Total, Fair Value	1,286	1,434
Obligations Issued by States and Political Subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	213,241	157,838
Gross Unrealized Losses	403	878
Total, Fair Value	212,838	156,960
Other Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	5,100	4,600
Gross Unrealized Gains		3
Gross Unrealized Losses	158	130
Total, Fair Value	4,942	4,473
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	116	153
Gross Unrealized Gains	145	99
Total, Fair Value	$ 261	$ 252

Securities Available-for-Sale29

Securities Available-for-Sale - Additional Information (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2016USD ($)Security	Jun. 30, 2015USD ($)	Jun. 30, 2016USD ($)Security	Jun. 30, 2015USD ($)	Dec. 31, 2015USD ($)Security
Schedule of Available-for-sale Securities [Line Items]
Securities at fair value pledged to secure public deposits and repurchase agreements	$ 1,185,127,000		$ 1,185,127,000		$ 1,004,743,000
Securities available-for-sale are securities pledged for borrowing	66,454,000		66,454,000		$ 20,056,000
Net gains on sales of securities	$ 45,000	$ 118,000	45,000	$ 118,000
Proceeds from sales of securities available-for-sale			$ 1,946,000	21,215,000
Securities AFS [Member]
Schedule of Available-for-sale Securities [Line Items]
Weighted average remaining life of investment securities available-for-sale			3 years 6 months
Number of securities, temporarily impaired for less than 12 months | Security	37		37		14
Number of securities, temporarily impaired for 12 months or longer | Security	10		10		11
Number of securities, temporarily impaired, total | Security	327		327		290
Federal Home Loan Bank Boston [Member]
Schedule of Available-for-sale Securities [Line Items]
Net gains on sales of securities			$ 33,000	$ 118,000
U.S. Government Agency and Sponsored Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities at fair value pledged to secure public deposits and repurchase agreements	$ 220,489,000		220,489,000		$ 220,482,000
U.S. Government Sponsored Enterprises [Member] | Securities AFS [Member]
Schedule of Available-for-sale Securities [Line Items]
Weighted average remaining life	$ 15,000,000		$ 15,000,000

Securities Available-for-Sale30

Securities Available-for-Sale - Maturity Distribution of Securities Available-for-Sale (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Within one year, Amortized Cost	$ 217,903
After one but within five years, Amortized Cost	232,419
After five but within ten years, Amortized Cost	105,748
More than ten years, Amortized Cost	5,700
Non-maturing, Amortized Cost	1,616
Amortized Cost	563,386	$ 404,977
Within one year, Fair Value	217,912
After one but within five years, Fair Value	232,311
After five but within ten years, Fair Value	105,767
More than ten years, Fair Value	5,292
Non-maturing, Fair Value	1,651
Total, Fair Value	$ 562,933	$ 404,623

Securities Available-for-Sale31

Securities Available-for-Sale - Continuous Unrealized Loss Position for 12 Months or Less and 12 Months or Longer (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value	$ 140,208	$ 30,036
Less Than 12 Months, Unrealized Losses	445	67
12 Months or Longer, Fair Value	34,448	55,024
12 Months or Longer, Unrealized Losses	645	1,266
Total, Fair Value	174,656	85,060
Total, Unrealized Losses	1,090	1,333
U.S. Treasury [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value		1,989
Less Than 12 Months, Unrealized Losses		10
Total, Fair Value		1,989
Total, Unrealized Losses		10
SBA Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value	10,959	1,031
Less Than 12 Months, Unrealized Losses	24	2
12 Months or Longer, Fair Value	0
12 Months or Longer, Unrealized Losses	0
Total, Fair Value	10,959	1,031
Total, Unrealized Losses	24	2
U.S. Government Agency and Sponsored Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value	127,281	26,519
Less Than 12 Months, Unrealized Losses	372	52
12 Months or Longer, Fair Value	27,894	49,341
12 Months or Longer, Unrealized Losses	116	248
Total, Fair Value	155,175	75,860
Total, Unrealized Losses	488	300
Privately Issued Residential Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value	415
Less Than 12 Months, Unrealized Losses	2
12 Months or Longer, Fair Value	467	490
12 Months or Longer, Unrealized Losses	15	13
Total, Fair Value	882	490
Total, Unrealized Losses	17	13
Obligations Issued by States and Political Subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
12 Months or Longer, Fair Value	4,298	3,820
12 Months or Longer, Unrealized Losses	403	878
Total, Fair Value	4,298	3,820
Total, Unrealized Losses	403	878
Other Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value	1,553	497
Less Than 12 Months, Unrealized Losses	47	3
12 Months or Longer, Fair Value	1,789	1,373
12 Months or Longer, Unrealized Losses	111	127
Total, Fair Value	3,342	1,870
Total, Unrealized Losses	$ 158	$ 130

Investment Securities Held-to32

Investment Securities Held-to-Maturity - Summary of Held-to-Maturity Securities (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 1,573,829	$ 1,438,903
Gross Unrealized Gains	33,559	9,781
Gross Unrealized Losses	630	9,724
Estimated Fair Value	1,606,758	1,438,960
U.S. Government Sponsored Enterprises [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	190,026	186,734
Gross Unrealized Gains	3,240	2,234
Gross Unrealized Losses	1	141
Estimated Fair Value	193,265	188,827
SBA Backed Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	20,987
Gross Unrealized Gains	155
Estimated Fair Value	21,142
U.S. Government Agency and Sponsored Mortgage Backed Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	1,362,816	1,252,169
Gross Unrealized Gains	30,164	7,547
Gross Unrealized Losses	629	9,583
Estimated Fair Value	$ 1,392,351	$ 1,250,133

Investment Securities Held-to33

Investment Securities Held-to-Maturity - Additional Information (Detail)	3 Months Ended	6 Months Ended
	Jun. 30, 2016USD ($)Security	Jun. 30, 2016USD ($)Security	Jun. 30, 2015USD ($)	Dec. 31, 2015USD ($)Security
Schedule of Held-to-maturity Securities [Line Items]
Securities at fair value pledged to secure public deposits and repurchase agreements	$ 1,185,127,000	$ 1,185,127,000		$ 1,004,743,000
Realized gross gains from sales of securities held-to-maturity		12,000
Proceeds from sales of securities held-to-maturity		$ 192,000	$ 0
Held-to-Maturity Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Weighted average remaining life of investment securities held-to-maturity	3 years 9 months 18 days
Number of securities, temporarily impaired for less than 12 months | Security	6	6		101
Number of securities, temporarily impaired for 12 months or longer | Security	16	16		26
Number of securities, temporarily impaired, total | Security	352	352		322
Held-to-Maturity Securities [Member] | U.S. Government Sponsored Enterprises [Member]
Schedule of Held-to-maturity Securities [Line Items]
Weighted average remaining life	$ 101,745,000	$ 101,745,000
Federal Home Loan Bank Boston [Member]
Schedule of Held-to-maturity Securities [Line Items]
Securities pledged for borrowing at the Federal Home Loan Bank	$ 356,261,000	$ 356,261,000		$ 432,965,000

Investment Securities Held-to34

Investment Securities Held-to-Maturity - Company's Securities Held-to-Maturity (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Within one year, Amortized Cost	$ 10,047
After one but within five years, Amortized Cost	1,400,716
After five but within ten years, Amortized Cost	159,917
More than ten years, Amortized Cost	3,149
Amortized Cost	1,573,829	$ 1,438,903
Within one year, Fair Value	10,137
After one but within five years, Fair Value	1,427,594
After five but within ten years, Fair Value	165,817
More than ten years, Fair Value	3,210
Estimated Fair Value	$ 1,606,758	$ 1,438,960

Investment Securities Held-to35

Investment Securities Held-to-Maturity - Unrealized Market Loss of Securities (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Schedule of Held-to-maturity Securities [Line Items]
Less Than 12 Months, Fair Value	$ 38,086	$ 636,077
Less Than 12 Months, Unrealized Losses	94	6,798
12 Months or Longer, Fair Value	70,461	123,864
12 Months or Longer, Unrealized Losses	536	2,926
Total, Fair Value	108,547	759,941
Total, Unrealized Losses	630	9,724
U.S. Government Sponsored Enterprises [Member]
Schedule of Held-to-maturity Securities [Line Items]
Less Than 12 Months, Fair Value	14,999	9,859
Less Than 12 Months, Unrealized Losses	1	141
Total, Fair Value	14,999	9,859
Total, Unrealized Losses	1	141
U.S. Government Agency and Sponsored Mortgage Backed Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Less Than 12 Months, Fair Value	23,087	626,218
Less Than 12 Months, Unrealized Losses	93	6,657
12 Months or Longer, Fair Value	70,461	123,864
12 Months or Longer, Unrealized Losses	536	2,926
Total, Fair Value	93,548	750,082
Total, Unrealized Losses	$ 629	$ 9,583

Allowance for Loan Losses - Sum

Allowance for Loan Losses - Summary of Changes in Allowance for Loan Losses (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Receivables [Abstract]
Allowance for loan losses, beginning of period	$ 23,544	$ 22,529	$ 23,075	$ 22,318
Loans charged off	(111)	(403)	(180)	(484)
Recoveries on loans previously charged-off	164	119	252	211
Net recoveries (charge-offs)	53	(284)	72	(273)
Provision charged to expense	350		800	200
Reclassification to other liabilities	(84)		(84)
Allowance for loan losses, end of period	$ 23,863	$ 22,245	$ 23,863	$ 22,245

Allowance for Loan Losses - S37

Allowance for Loan Losses - Summary of Allowance for Loan Losses (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Allowance for loan losses:
Allowance for loan losses, beginning of period	$ 23,544	$ 22,529	$ 23,075	$ 22,318
Charge-offs	(111)	(403)	(180)	(484)
Recoveries	164	119	252	211
Provision	350		800	200
Reclassification to other liabilities	(84)		(84)
Allowance for loan losses, end of period	23,863	22,245	23,863	22,245
Amount of allowance for loan losses for loans deemed to be impaired	174	295	174	295
Amount of allowance for loan losses for loans not deemed to be impaired	23,689	21,950	23,689	21,950
Loans:
Total loans, net	1,801,904	1,544,694	1,801,904	1,544,694	$ 1,731,536
Loans deemed to be impaired	4,457	3,433	4,457	3,433
Loans not deemed to be impaired	1,797,447	1,541,261	1,797,447	1,541,261
Construction and Land Development [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	1,973	1,884	2,041	1,592
Provision	264	(151)	196	141
Reclassification to other liabilities	(3)		(3)
Allowance for loan losses, end of period	2,234	1,733	2,234	1,733
Amount of allowance for loan losses for loans deemed to be impaired	6	12	6	12
Amount of allowance for loan losses for loans not deemed to be impaired	2,228	1,721	2,228	1,721
Loans:
Total loans, net	31,178	26,521	31,178	26,521	27,421
Loans deemed to be impaired	96	101	96	101
Loans not deemed to be impaired	31,082	26,420	31,082	26,420
Commercial and Industrial [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	6,693	4,645	5,899	4,758
Charge-offs		(52)		(52)
Recoveries	56	56	91	71
Provision	(878)	(221)	(119)	(349)
Reclassification to other liabilities	(29)		(29)
Allowance for loan losses, end of period	5,842	4,428	5,842	4,428
Amount of allowance for loan losses for loans deemed to be impaired	10	43	10	43
Amount of allowance for loan losses for loans not deemed to be impaired	5,832	4,385	5,832	4,385
Loans:
Total loans, net	493,033	291,142	493,033	291,142	452,235
Loans deemed to be impaired	410	595	410	595
Loans not deemed to be impaired	492,623	290,547	492,623	290,547
Municipal [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	990	1,373	994	1,488
Provision	811	(373)	807	(488)
Allowance for loan losses, end of period	1,801	1,000	1,801	1,000
Amount of allowance for loan losses for loans deemed to be impaired	0		0
Amount of allowance for loan losses for loans not deemed to be impaired	1,801	1,000	1,801	1,000
Loans:
Total loans, net	134,386	87,241	134,386	87,241	85,685
Loans not deemed to be impaired	134,386	87,241	134,386	87,241
Commercial Real Estate [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	10,533	11,127	10,589	11,199
Charge-offs		(298)		(298)
Recoveries		2		4
Provision	128	892	72	818
Reclassification to other liabilities	(11)		(11)
Allowance for loan losses, end of period	10,650	11,723	10,650	11,723
Amount of allowance for loan losses for loans deemed to be impaired	151	108	151	108
Amount of allowance for loan losses for loans not deemed to be impaired	10,499	11,615	10,499	11,615
Loans:
Total loans, net	728,658	713,770	728,658	713,770	721,506
Loans deemed to be impaired	3,736	1,705	3,736	1,705
Loans not deemed to be impaired	724,922	712,065	724,922	712,065
Residential Real Estate [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	1,249	799	1,320	775
Charge-offs			0
Recoveries	2	2	3	4
Provision	53	(79)	(19)	(57)
Reclassification to other liabilities	(2)		(2)
Allowance for loan losses, end of period	1,302	722	1,302	722
Amount of allowance for loan losses for loans deemed to be impaired	7	41	7	41
Amount of allowance for loan losses for loans not deemed to be impaired	1,295	681	1,295	681
Loans:
Total loans, net	219,494	248,103	219,494	248,103	255,346
Loans deemed to be impaired	215	941	215	941
Loans not deemed to be impaired	219,279	247,162	219,279	247,162
Consumer [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	693	714	644	810
Charge-offs	(111)	(53)	(180)	(134)
Recoveries	106	59	158	132
Provision	(77)	(11)	(11)	(99)
Reclassification to other liabilities	(3)		(3)
Allowance for loan losses, end of period	608	709	608	709
Amount of allowance for loan losses for loans not deemed to be impaired	608	709	608	709
Loans:
Total loans, net	11,339	10,646	11,339	10,646	11,323
Loans not deemed to be impaired	11,339	10,646	11,339	10,646
Home Equity [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	1,185	614	1,077	599
Provision	9	36	117	51
Reclassification to other liabilities	(36)		(36)
Allowance for loan losses, end of period	1,158	650	1,158	650
Amount of allowance for loan losses for loans deemed to be impaired		91		91
Amount of allowance for loan losses for loans not deemed to be impaired	1,158	559	1,158	559
Loans:
Total loans, net	183,816	167,271	183,816	167,271	$ 178,020
Loans deemed to be impaired		91		91
Loans not deemed to be impaired	183,816	167,180	183,816	167,180
Unallocated [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	228	1,373	511	1,097
Provision	40	(93)	(243)	183
Allowance for loan losses, end of period	268	1,280	268	1,280
Amount of allowance for loan losses for loans not deemed to be impaired	$ 268	$ 1,280	$ 268	$ 1,280

Allowance for Loan Losses - Loa

Allowance for Loan Losses - Loans by Risk Rating (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
Loans by risk rating
Financing Receivable, Net	$ 1,801,904	$ 1,731,536	$ 1,544,694
Construction and Land Development [Member]
Loans by risk rating
Financing Receivable, Net	31,178	27,421	26,521
Construction and Land Development [Member] | 1-3 (Pass) [Member]
Loans by risk rating
Financing Receivable, Net	24,048	20,281
Construction and Land Development [Member] | 4 (Monitor) [Member]
Loans by risk rating
Financing Receivable, Net	7,034	7,042
Construction and Land Development [Member] | Impaired [Member]
Loans by risk rating
Financing Receivable, Net	96	98
Commercial and Industrial [Member]
Loans by risk rating
Financing Receivable, Net	493,033	452,235	291,142
Commercial and Industrial [Member] | 1-3 (Pass) [Member]
Loans by risk rating
Financing Receivable, Net	492,623	451,774
Commercial and Industrial [Member] | 4 (Monitor) [Member]
Loans by risk rating
Financing Receivable, Net		18
Commercial and Industrial [Member] | Impaired [Member]
Loans by risk rating
Financing Receivable, Net	410	443
Municipal [Member]
Loans by risk rating
Financing Receivable, Net	134,386	85,685	87,241
Municipal [Member] | 1-3 (Pass) [Member]
Loans by risk rating
Financing Receivable, Net	134,386	85,685
Commercial Real Estate [Member]
Loans by risk rating
Financing Receivable, Net	728,658	721,506	$ 713,770
Commercial Real Estate [Member] | 1-3 (Pass) [Member]
Loans by risk rating
Financing Receivable, Net	724,735	718,911
Commercial Real Estate [Member] | 4 (Monitor) [Member]
Loans by risk rating
Financing Receivable, Net	187	917
Commercial Real Estate [Member] | Impaired [Member]
Loans by risk rating
Financing Receivable, Net	$ 3,736	$ 1,678

Allowance for Loan Losses - L39

Allowance for Loan Losses - Loans by Credit Ratings Issued by National Organizations (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable net of deferred income credit quality	$ 859,039	$ 765,695
Aaa - Aa3 [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable net of deferred income credit quality	357,928	306,145
A1 - A3 [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable net of deferred income credit quality	277,876	278,691
Baa1 - Baa3 [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable net of deferred income credit quality	219,625	176,379
Ba2 [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable net of deferred income credit quality	3,610	4,480
Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable net of deferred income credit quality	422,372	375,152
Commercial and Industrial [Member] | Aaa - Aa3 [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable net of deferred income credit quality	282,048	234,733
Commercial and Industrial [Member] | A1 - A3 [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable net of deferred income credit quality	140,324	140,419
Municipal [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable net of deferred income credit quality	133,336	84,635
Municipal [Member] | Aaa - Aa3 [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable net of deferred income credit quality	68,806	63,865
Municipal [Member] | A1 - A3 [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable net of deferred income credit quality	7,400	7,400
Municipal [Member] | Baa1 - Baa3 [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable net of deferred income credit quality	53,520	8,890
Municipal [Member] | Ba2 [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable net of deferred income credit quality	3,610	4,480
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable net of deferred income credit quality	303,331	305,908
Commercial Real Estate [Member] | Aaa - Aa3 [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable net of deferred income credit quality	7,074	7,547
Commercial Real Estate [Member] | A1 - A3 [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable net of deferred income credit quality	130,152	130,872
Commercial Real Estate [Member] | Baa1 - Baa3 [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable net of deferred income credit quality	$ 166,105	$ 167,489

Allowance for Loan Losses - Agi

Allowance for Loan Losses - Aging of Past Due Loans (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
Financing Receivable, Allowance for Credit Losses [Line Items]
Accruing 30-89 Days Past Due	$ 2,646	$ 2,692
Non Accrual	1,486	2,336
Total Past Due	4,132	5,028
Current Loans	1,797,772	1,726,508
Total loans, net	1,801,904	1,731,536	$ 1,544,694
Construction and Land Development [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Non Accrual	96	99
Total Past Due	96	99
Current Loans	31,082	27,322
Total loans, net	31,178	27,421	26,521
Commercial and Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Accruing 30-89 Days Past Due	470
Non Accrual	52	60
Total Past Due	522	60
Current Loans	492,511	452,175
Total loans, net	493,033	452,235	291,142
Municipal [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Current Loans	134,386	85,685
Total loans, net	134,386	85,685	87,241
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Accruing 30-89 Days Past Due	1,080	1,462
Non Accrual	162	174
Total Past Due	1,242	1,636
Current Loans	727,416	719,870
Total loans, net	728,658	721,506	713,770
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Accruing 30-89 Days Past Due	736	596
Non Accrual	844	1,559
Total Past Due	1,580	2,155
Current Loans	217,914	253,191
Total loans, net	219,494	255,346	248,103
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Accruing 30-89 Days Past Due	1	6
Non Accrual	3
Total Past Due	4	6
Current Loans	11,335	11,317
Total loans, net	11,339	11,323	10,646
Home Equity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Accruing 30-89 Days Past Due	359	628
Non Accrual	329	444
Total Past Due	688	1,072
Current Loans	183,128	176,948
Total loans, net	$ 183,816	$ 178,020	$ 167,271

Allowance for Loan Losses - Inf

Allowance for Loan Losses - Information Pertaining to Impaired Loans (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Financing Receivable, Allowance for Credit Losses [Line Items]
With no required reserve recorded, Carrying Value	$ 751	$ 158	$ 751	$ 158
With no required reserve recorded, Unpaid Principal Balance	1,025	242	1,025	242
With no required reserve recorded, Required Reserve	0	0	0	0
With no required reserve recorded, Average Carrying Value Recognized	489	372	352	451
With no required reserve recorded, Interest Income	18	2	26	4
With required reserve recorded, Carrying Value	3,706	3,275	3,706	3,275
With required reserve recorded, Unpaid Principal Balance	3,832	3,580	3,832	3,580
With required reserve recorded, Required Reserve	174	295	174	295
With required reserve recorded, Average Carrying Value Recognized	2,802	4,463	2,905	5,022
With required reserve recorded, Interest Income	26	23	45	51
Carrying Value	4,457	3,433	4,457	3,433
Unpaid Principal Balance	4,857	3,822	4,857	3,822
With required reserve recorded, Required Reserve	174	295	174	295
Average Carrying Value Recognized	3,291	4,835	3,257	5,473
Interest Income	44	25	71	55
Construction and Land Development [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
With no required reserve recorded, Required Reserve	0	0	0	0
With required reserve recorded, Carrying Value	96	101	96	101
With required reserve recorded, Unpaid Principal Balance	108	108	108	108
With required reserve recorded, Required Reserve	6	12	6	12
With required reserve recorded, Average Carrying Value Recognized	97	102	97	102
Carrying Value	96	101	96	101
Unpaid Principal Balance	108	108	108	108
With required reserve recorded, Required Reserve	6	12	6	12
Average Carrying Value Recognized	97	102	97	102
Commercial and Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
With no required reserve recorded, Carrying Value	52	32	52	32
With no required reserve recorded, Unpaid Principal Balance	239	32	239	32
With no required reserve recorded, Required Reserve	0	0	0	0
With no required reserve recorded, Average Carrying Value Recognized	54	47	56	40
With required reserve recorded, Carrying Value	358	563	358	563
With required reserve recorded, Unpaid Principal Balance	373	765	373	765
With required reserve recorded, Required Reserve	10	43	10	43
With required reserve recorded, Average Carrying Value Recognized	370	644	374	722
With required reserve recorded, Interest Income	5	5	9	11
Carrying Value	410	595	410	595
Unpaid Principal Balance	612	797	612	797
With required reserve recorded, Required Reserve	10	43	10	43
Average Carrying Value Recognized	424	691	430	762
Interest Income	5	5	9	11
Municipal [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
With required reserve recorded, Required Reserve	0		0
With required reserve recorded, Required Reserve	0		0
Municipal [Member] | Municipal [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
With no required reserve recorded, Required Reserve	0	0	0	0
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
With no required reserve recorded, Carrying Value	596		596
With no required reserve recorded, Unpaid Principal Balance	596		596
With no required reserve recorded, Required Reserve	0	0	0	0
With no required reserve recorded, Average Carrying Value Recognized	329	196	188	280
With no required reserve recorded, Interest Income	16		22
With required reserve recorded, Carrying Value	3,140	1,705	3,140	1,705
With required reserve recorded, Unpaid Principal Balance	3,239	1,801	3,239	1,801
With required reserve recorded, Required Reserve	151	108	151	108
With required reserve recorded, Average Carrying Value Recognized	2,030	2,809	1,878	3,286
With required reserve recorded, Interest Income	20	17	33	33
Carrying Value	3,736	1,705	3,736	1,705
Unpaid Principal Balance	3,835	1,801	3,835	1,801
With required reserve recorded, Required Reserve	151	108	151	108
Average Carrying Value Recognized	2,359	3,005	2,066	3,566
Interest Income	36	17	55	33
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
With no required reserve recorded, Carrying Value	103	126	103	126
With no required reserve recorded, Unpaid Principal Balance	190	210	190	210
With no required reserve recorded, Required Reserve	0	0	0	0
With no required reserve recorded, Average Carrying Value Recognized	106	129	108	131
With no required reserve recorded, Interest Income	2	2	4	4
With required reserve recorded, Carrying Value	112	815	112	815
With required reserve recorded, Unpaid Principal Balance	112	815	112	815
With required reserve recorded, Required Reserve	7	41	7	41
With required reserve recorded, Average Carrying Value Recognized	283	817	505	820
With required reserve recorded, Interest Income	1	1	3	7
Carrying Value	215	941	215	941
Unpaid Principal Balance	302	1,025	302	1,025
With required reserve recorded, Required Reserve	7	41	7	41
Average Carrying Value Recognized	389	946	613	951
Interest Income	3	3	7	11
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
With no required reserve recorded, Required Reserve	0	0	0	0
Home Equity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
With no required reserve recorded, Required Reserve	0	0	0	0
With required reserve recorded, Carrying Value		91		91
With required reserve recorded, Unpaid Principal Balance		91		91
With required reserve recorded, Required Reserve		91		91
With required reserve recorded, Average Carrying Value Recognized	22	91	51	92
Carrying Value		91		91
Unpaid Principal Balance		91		91
With required reserve recorded, Required Reserve		91		91
Average Carrying Value Recognized	$ 22	$ 91	$ 51	$ 92

Allowance for Loan Losses - Add

Allowance for Loan Losses - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2016USD ($)Contracts	Jun. 30, 2015USD ($)
Financing Receivable, Allowance for Credit Losses [Line Items]
Troubled debt restructurings, subsequently defaulted		$ 0
Commercial Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Number of troubled debt restructurings | Contracts	1
Pre-modification outstanding recorded investment	$ 2,091,000
Post-modification outstanding recorded investment	2,091,000
Financing allowance reduction in principal payments	3,000
Financing allowance reduction in interest payments	$ 1,000

Reclassifications Out of Accu43

Reclassifications Out of Accumulated Other Comprehensive Income - Reclassifications Out of Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net gains on sales of securities	$ 45	$ 118	$ 45	$ 118
Provision for income taxes	(20)	(233)	(84)	(448)
Net income	6,241	5,925	11,549	10,884
Salaries and employee benefits	(10,040)	(9,480)	(19,816)	(18,614)
Reclassification Out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income	(978)	(1,169)	(2,205)	(2,117)
Reclassification Out of Accumulated Other Comprehensive Income [Member] | Unrealized Gains and Losses on Available-for-Sale Securities [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net gains on sales of securities	45	118	45	118
Provision for income taxes	(18)	(47)	(18)	(47)
Net income	27	71	27	71
Reclassification Out of Accumulated Other Comprehensive Income [Member] | Accretion of Unrealized Losses Transferred [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net gains on sales of securities	(1,170)	(1,576)	(2,682)	(2,705)
Provision for income taxes	408	549	935	943
Net income	(762)	(1,027)	(1,747)	(1,762)
Reclassification Out of Accumulated Other Comprehensive Income [Member] | Prior-Service Costs [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Salaries and employee benefits	(3)	(3)	(5)	(6)
Reclassification Out of Accumulated Other Comprehensive Income [Member] | Actuarial Gains (Losses) [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Salaries and employee benefits	(401)	(352)	(802)	(704)
Reclassification Out of Accumulated Other Comprehensive Income [Member] | Amortization of Defined Benefit Pension Items [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before taxes	(404)	(355)	(807)	(710)
Provision for income taxes	161	142	322	284
Net income	$ (243)	$ (213)	$ (485)	$ (426)

Earnings per Share ("EPS") - Ad

Earnings per Share ("EPS") - Additional Information (Detail) - Class A Common Stock [Member] - shares	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Number of Stock options outstanding	0	0
Minimum [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Class A common stock entitled dividend per share percent in comparison to Class B common stock	200.00%

Earnings Per Share ("EPS") - Re

Earnings Per Share ("EPS") - Reconciliation of Basic EPS and Diluted EPS (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income	$ 6,241	$ 5,925	$ 11,549	$ 10,884
Class A Common Stock [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income	$ 4,902	$ 4,654	$ 9,071	$ 8,549
Weighted average shares outstanding, basic	3,600,729	3,600,729	3,600,729	3,600,729
Basic earnings per share	$ 1.36	$ 1.29	$ 2.52	$ 2.37
Weighted average shares outstanding, diluted	5,567,909	5,567,909	5,567,909	5,567,909
Diluted earnings per share	$ 1.12	$ 1.06	$ 2.07	$ 1.95
Class B Common Stock [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income	$ 1,339	$ 1,271	$ 2,478	$ 2,335
Weighted average shares outstanding, basic	1,967,180	1,967,180	1,967,180	1,967,180
Basic earnings per share	$ 0.68	$ 0.65	$ 1.26	$ 1.19
Weighted average shares outstanding, diluted	1,967,180	1,967,180	1,967,180	1,967,180
Diluted earnings per share	$ 0.68	$ 0.65	$ 1.26	$ 1.19

Employee Benefits - Additional

Employee Benefits - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2016USD ($)
Compensation and Retirement Disclosure [Abstract]
Number of years service to participate in supplemental plan	1 year
Current fiscal year contribution to pension plan	$ 1,575,000
Employer expected contribution to Pension Plan in 2015	$ 2,075,000

Employee Benefits - Components

Employee Benefits - Components of Net Periodic Benefit Cost (Credit) (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Defined Benefit Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 318	$ 336	$ 636	$ 672
Interest	340	394	680	788
Expected return on plan assets	(694)	(688)	(1,388)	(1,376)
Recognized prior service cost (benefit)	(26)	(26)	(52)	(52)
Recognized net actuarial losses	200	204	400	407
Net periodic benefit (credit) cost	138	220	276	439
Supplemental Insurance/ Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	455	397	910	794
Interest	334	341	668	682
Expected return on plan assets	0		0
Recognized prior service cost (benefit)	29	29	58	58
Recognized net actuarial losses	200	149	400	299
Net periodic benefit (credit) cost	$ 1,018	$ 916	$ 2,036	$ 1,833

Fair Value Measurements - Finan

Fair Value Measurements - Financial Instruments Measured at Fair Value on a Recurring and Non-recurring Basis (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	$ 562,933	$ 404,623
Fair Value Measurements, Level 1 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	261	215
Fair Value Measurements, Level 2 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	349,834	247,411
Fair Value Measurements, Level 3 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	212,838	156,997
Financial Instruments Measured at Fair Value on a Non-recurring Basis
Impaired Loans	259	1,056
U.S. Treasury [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	2,000	1,989
U.S. Treasury [Member] | Fair Value Measurements, Level 2 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	2,000	1,989
SBA Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	45,705	5,989
SBA Backed Securities [Member] | Fair Value Measurements, Level 2 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	45,705	5,989
U.S. Government Agency and Sponsored Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	280,877	233,526
U.S. Government Agency and Sponsored Mortgage Backed Securities [Member] | Fair Value Measurements, Level 2 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	280,877	233,526
Privately Issued Residential Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	1,286	1,434
Privately Issued Residential Mortgage Backed Securities [Member] | Fair Value Measurements, Level 2 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	1,286	1,434
Obligations Issued by States and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	212,838	156,960
Obligations Issued by States and Political Subdivisions [Member] | Fair Value Measurements, Level 3 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	212,838	156,960
Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	4,942	4,473
Other Debt Securities [Member] | Fair Value Measurements, Level 2 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	4,942	4,473
Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	261	252
Equity Securities [Member] | Fair Value Measurements, Level 1 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	261	215
Equity Securities [Member] | Fair Value Measurements, Level 3 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS		37
U.S. Government Sponsored Enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	15,024
U.S. Government Sponsored Enterprises [Member] | Fair Value Measurements, Level 2 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	15,024
Carrying Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	562,933	404,623
Financial Instruments Measured at Fair Value on a Non-recurring Basis
Impaired Loans	259	1,056
Carrying Value [Member] | U.S. Treasury [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	2,000	1,989
Carrying Value [Member] | SBA Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	45,705	5,989
Carrying Value [Member] | U.S. Government Agency and Sponsored Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	280,877	233,526
Carrying Value [Member] | Privately Issued Residential Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	1,286	1,434
Carrying Value [Member] | Obligations Issued by States and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	212,838	156,960
Carrying Value [Member] | Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	4,942	4,473
Carrying Value [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	261	$ 252
Carrying Value [Member] | U.S. Government Sponsored Enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities AFS	$ 15,024

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) - USD ($)	3 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2016	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Specific adjustments to impaired loans recognized	$ (122,000)	$ (136,000)	$ 165,000
Transfers between level 1, 2 and 3		0
Liabilities measured at fair value on a recurring or nonrecurring basis	0	0
Transfers between level 1, 2 and 3			0
Liabilities measured at fair value on a recurring or nonrecurring basis			$ 0
Fair Value Measurements, Level 3 Inputs [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Amortized cost of Level 3 securities	213,241,000	213,241,000		$ 153,454,000
Unrealized loss	$ 403,000	$ 403,000		$ 876,000

Fair Value Measurements - Asset

Fair Value Measurements - Assets Measured at Fair Value (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Securities AFS [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Fair Value	$ 212,838	$ 156,997
Valuation Technique	Discounted cash flow
Unobservable Input	Discount rate
Impaired Loans [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Fair Value	$ 259	$ 1,056
Valuation Technique	Appraisal of collateral
Unobservable Input	Appraisal adjustments
Minimum [Member] | Securities AFS [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Unobservable Input Value or Range	0.00%	0.00%
Minimum [Member] | Impaired Loans [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Unobservable Input Value or Range	0.00%	0.00%
Maximum [Member] | Securities AFS [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Unobservable Input Value or Range	1.00%	1.00%
Maximum [Member] | Impaired Loans [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Unobservable Input Value or Range	30.00%	30.00%

Fair Value Measurements - Ass51

Fair Value Measurements - Assets Measured at Fair Value (Parenthetical) (Detail)	6 Months Ended
	Jun. 30, 2016
Municipal [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Securities maturity period	one year or less

Fair Value Measurements - Chang

Fair Value Measurements - Changes in Level 3 Securities (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	$ 156,997	$ 96,886
Purchases	155,742	113,179
Maturities and calls	(100,282)	(57,476)
Amortization	(97)	(11)
Changes in fair value	478
Ending Balance	212,838	152,578
Auction Rate Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	3,820	3,820
Changes in fair value	478
Ending Balance	4,298	3,820
Obligations Issued by States and Political Subdivisions [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	153,140	92,964
Purchases	155,742	113,179
Maturities and calls	(100,245)	(57,411)
Amortization	(97)	(11)
Ending Balance	208,540	148,721
Equity Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	37	102
Maturities and calls	$ (37)	(65)
Ending Balance		$ 37

Fair Values of Financial Inst53

Fair Values of Financial Instruments - Carrying Amount and Fair Value of Company's Financial Instruments (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Financial assets:
Securities held-to-maturity	$ 1,573,829	$ 1,438,903
Loans held-for-sale	12,403
Loans	1,778,041	1,708,461
Financial liabilities:
Time deposits	460,527	473,426
Other borrowed funds	431,000	368,000
Subordinated debentures	36,083	36,083
Carrying Value [Member]
Financial assets:
Securities held-to-maturity	1,573,829	1,438,903
Loans held-for-sale	12,403
Loans	1,778,041	1,708,461
Financial liabilities:
Time deposits	460,527	473,426
Other borrowed funds	431,000	368,000
Subordinated debentures	36,083	36,083
Estimated Fair Value [Member]
Financial assets:
Securities held-to-maturity	1,606,758	1,438,960
Loans held-for-sale	12,704
Loans	1,808,359	1,677,270
Financial liabilities:
Time deposits	464,613	474,046
Other borrowed funds	439,956	372,209
Subordinated debentures	36,083	36,083
Fair Value Measurements, Level 2 Inputs [Member]
Financial assets:
Securities held-to-maturity	1,606,758	1,438,960
Loans held-for-sale	12,704
Financial liabilities:
Time deposits	464,613	474,046
Other borrowed funds	439,956	372,209
Fair Value Measurements, Level 3 Inputs [Member]
Financial assets:
Loans	1,808,359	1,677,270
Financial liabilities:
Subordinated debentures	$ 36,083	$ 36,083