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