Accumulated Other Comprehensive Income (Loss) (Components of OCI) (Details 1) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Foreign currency translation adjustments:
Translation adjustments arising during the period, before tax	$ (16,061)	$ (1,059)	$ 5,622
Translation adjustments arising during the period, income tax	0	0	0
Translation adjustments arising during the period, after tax	(16,061)	(1,059)	5,622
Adjustment for sales of businesses with foreign operations, before tax	(404)	0	(888)
Adjustment for sales of businesses with foreign operations, income tax	0		0
Adjustment for sales of businesses with foreign operations, after tax	(404)		(888)
Total foreign currency translation adjustments, before tax	(16,465)	(1,059)	4,734
Total foreign currency translation adjustments, income tax	0		0
Total foreign currency translation adjustments, after tax	(16,465)		4,734
Unrealized gains (losses) on available-for-sale securities:
Unrealized gains (losses) for the period, before tax	62,719	95,629	33,098
Unrealized gains (losses) for the period, income tax	(25,088)	(38,251)	(13,239)
Unrealized gains (losses) for the period, after tax	37,631	57,378	19,859
Reclassification adjustment for realization of (gain) loss on exchange, sale or write-down of available-for-sale securities included in net income, before tax	(265,274)	9,554	17,226
Reclassification adjustment for realization of (gain) loss on exchange, sale or write-down of available-for-sale securities included in net income, income tax	106,110	(3,822)	(6,890)
Reclassification adjustment for realization of (gain) loss on exchange, sale or write-down of available-for-sale securities included in net income, after tax	(159,164)	5,732	10,336
Total unrealized gains (losses) on available-for-sale securities, before tax	(202,555)	105,183	50,324
Total unrealized gains (losses) on available-for-sale securities, income tax	81,022	(42,073)	(20,129)
Total unrealized gains (losses) on available-for-sale securities, after tax	(121,533)	63,110	30,195
Pension and other postretirement plans:
Actuarial (loss) gain	(149,482)	762,806	82,470
Actuarial (loss) gain, income tax	59,792	(305,123)	(32,987)
Actuarial (loss) gain, after tax	(89,690)	457,683	49,483
Prior service cost, before tax	(1,600)	0	0
Prior service cost, income tax	640
Prior service cost, after tax	(960)
Amortization of net actuarial (gain) loss included in net income, before tax	(29,412)	3,096	9,368
Amortization of net actuarial (gain) loss included in net income, income tax	11,765	(1,238)	(3,746)
Amortization of net actuarial (gain) loss included in net income, after tax	(17,647)	1,858	5,622
Amortization of net prior service credit included in net income	(407)	(1,383)	(1,859)
Amortization of net prior service credit included in net income, income tax	163	553	744
Amortization of net prior service credit included in net income, after tax	(244)	(830)	(1,115)
Curtailment and settlement gain included in net income, before tax	8	(124,051)	0
Curtailment and settlement gain included in net income, income tax	(3)	49,617
Curtailment and settlement gain included in net income, after tax	5	(74,434)
Other Adjustments, before tax	0	0	(745)
Other adjustments, income tax			299
Other adjustments, net of tax			(446)
Total pension and other postretirement plans, before tax	(180,893)	640,468	89,234
Total pension and other postretirement plans, income tax	72,357	(256,191)	(35,690)
Total pension and other postretirement plans, after tax	(108,536)	384,277	53,544
Cash flow hedge:
Gain (loss) for the period, before tax	867	520	(1,581)
Gain (loss) for the period, income tax	(347)	(208)	633
Gain (loss) for the period, after tax	520	312	(948)
Other Comprehensive (Loss) Income, Before Tax	(399,046)	745,112	142,711
Other Comprehensive (Loss) Income, Income Tax	153,032	(298,472)	(55,186)
Other Comprehensive (Loss) Income, Net of Tax	$ (246,014)	$ 446,640	$ 87,525