Pensions and Other Post-Retirement Benefits (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Plan Disclosure [Line Items]
Unfunded commitment for additional capital	$ 39,000,000
Expected required benefits 2014	24,300,000
Expected required benefits 2015	21,700,000
Expected required benefits 2016	17,100,000
Expected required benefits 2017	15,800,000
Expected required benefits 2018	13,900,000
Expected required benefits, Thereafter	27,600,000
Maximum annual contribution per employee (as a percent)	6.00%
Employer matching contribution (as a percent)	50.00%
Expense for Company's matching contribution	1,400,000	1,800,000	2,000,000
Minimum
Defined Benefit Plan Disclosure [Line Items]
Maximum annual contribution per employee (as a percent)	1.00%
Maximum
Defined Benefit Plan Disclosure [Line Items]
Maximum annual contribution per employee (as a percent)	75.00%
Other Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	19,400,000	22,600,000
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	353,973,000	330,471,000	346,408,000
Amortization period for pension plan actuarial gains (losses) (in years)	21 years	10 years	10 years
Amount of actuarial losses included in accumulated other comprehensive loss that is expected to be recognized in net periodic benefit cost	7,700,000
Amount of prior service cost included in accumulated other comprehensive loss that is expected to be recognized in net periodic benefit cost	0
Accumulated benefit obligation for all defined benefit pension plans	497,540,000	547,456,000	532,619,000
Expected required benefits 2014	34,813,000
Expected required benefits 2015	34,640,000
Expected required benefits 2016	34,456,000
Expected required benefits 2017	34,247,000
Expected required benefits 2018	34,018,000
Expected required benefits, Thereafter	163,182,000
Benefits paid	34,495,000	36,058,000
Other Post-Retirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0	0
Amount of actuarial losses included in accumulated other comprehensive loss that is expected to be recognized in net periodic benefit cost	0
Amount of prior service cost included in accumulated other comprehensive loss that is expected to be recognized in net periodic benefit cost	(100,000)
Accumulated benefit obligation for all defined benefit pension plans	1,084,000	4,208,000	4,092,000
Expected required benefits 2014	111,000
Expected required benefits 2015	118,000
Expected required benefits 2016	112,000
Expected required benefits 2017	100,000
Expected required benefits 2018	94,000
Expected required benefits, Thereafter	366,000
Benefits paid	$ 317,000	$ 206,000