CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Pension and other post retirement obligations:
Amortization of actuarial losses included in net periodic pension cost, gross	$ 375	$ 363
Tax effect	(144)	(140)
Amortization of actuarial losses included in net periodic pension cost, net	231	223
Amortization of prior service cost included in net periodic pension cost, gross	(34)	(43)
Tax effect	13	16
Amortization of prior service cost included in net periodic pension cost, net	(21)	(27)
Other comprehensive income related to pension and other post retirement obligations, net of taxes	210	196
Unrealized gains on available-for-sale securities:
Net unrealized holding gains arising during period, gross	67,257	31,389
Tax effect	(25,415)	(13,372)
Net unrealized holding gains arising during period, net	41,842	18,017
Other comprehensive income related to unrealized gains on available-for-sale securities, net of taxes	41,842	18,017
Other comprehensive income, net of tax	42,052	18,213
Net income	24,403	22,297
Comprehensive income	66,455	$ 40,510
Accumulated Other Comprehensive Income By Component:
Unrealized loss for pension and other postretirement obligations	(34,006)		$ (34,347)
Tax effect	12,933		13,064
Net unrealized loss for pension and other postretirement obligations	(21,073)		(21,283)
Unrealized gain on available-for-sale securities	133,092		65,835
Tax effect	(50,732)		(25,317)
Net unrealized gain on available-for-sale securities	82,360		40,518
Accumulated other comprehensive income	$ 61,287		$ 19,235