Pensions and Other Employee Benefits Plans (Reconciliation of Changes in Plans' Benefit Obligations and Fair Value of Assets) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at December 31,	$ 28,476	$ 24,628
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	188	311	824
Interest cost	1,882	1,843	2,523
Employer contributions	4,100
Funded status at end of period	(19,696)	(15,614)
Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	2	6
Interest cost	71	65	45
Employer contributions	100
Funded status at end of period	(1,623)	(1,517)
Reconciliation of Benefit Obligation [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Obligation at beginning of period	40,242	62,488
Service cost	188	311
Interest cost	1,882	1,843
Participant contributions	21	28
Actuarial (gain) loss	7,554	(3,874)
Benefit payments	(1,715)	(1,868)
Curtailment and settlement		(18,686)
Obligation at December 31	48,172	40,242
Reconciliation of Benefit Obligation [Member] | Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Obligation at beginning of period	1,517	1,051
Service cost	1	2
Interest cost	71	65
Participant contributions	58	51
Plan amendment		230
Actuarial (gain) loss	145	249
Benefit payments	(169)	(147)
Curtailment and settlement		16
Obligation at December 31	1,623	1,517
Reconciliation of Fair Value of Plan Assets [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Participant contributions	21	28
Benefit payments	(1,715)	(1,467)
Fair value of plan assets at beginning of period	24,628	20,207
Actual return on plan assets	1,464	3,120
Employer contributions	4,078	3,955
Transfer due to Sale		(1,215)
Fair value of plan assets at December 31,	28,476	24,628
Reconciliation of Fair Value of Plan Assets [Member] | Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Participant contributions	58	51
Benefit payments	(169)	(147)
Employer contributions	$ 111	$ 96