Pension, Savings and Postretirement Benefits (Details 2) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
	Dec. 31, 2013 item	Dec. 31, 2013	Dec. 31, 2012 item	Dec. 31, 2011
Components of cost recognized in other comprehensive loss
Balance at the beginning of the period		(16,574)	(15,345)
Change in pension and post-retirement health liabilities		6,391	(1,229)	(5,202)
Balance at the end of the period	(10,183)	(10,183)	(16,574)	(15,345)
Pension plans
Components of cost recognized in other comprehensive loss
Balance at the beginning of the period		(13,073)	(13,095)
Change in pension and post-retirement health liabilities		4,736	22
Balance at the end of the period	(8,337)	(8,337)	(13,073)
Estimated amount that will be amortized from accumulated other comprehensive loss into net periodic cost
Actuarial loss		264
Total		264
Hourly Plan
Weighted average assumptions used in determining the year-end benefit obligation
Discount rate (as a percent)	4.50%	4.50%	3.75%
Expected return on plan assets (as a percent)		7.00%	7.50%
Number of hourly defined benefit plans	2		2
Weighted average assumptions used to determine net periodic cost
Discount rate (as a percent)		3.75%	4.25%	5.50%
Expected return on plan assets (as a percent)		7.50%	8.00%	8.00%
Salaried Plan
Weighted average assumptions used in determining the year-end benefit obligation
Discount rate (as a percent)	4.75%	4.75%	4.00%
Expected return on plan assets (as a percent)		7.00%	7.50%
Number of salaried defined benefit plans	2
Weighted average assumptions used to determine net periodic cost
Discount rate (as a percent)		4.00%	4.50%	5.50%
Expected return on plan assets (as a percent)		7.50%	8.00%	8.00%
Postretirement Healthcare Coverage
Components of cost recognized in other comprehensive loss
Balance at the beginning of the period		(3,501)	(2,250)
Change in pension and post-retirement health liabilities		1,655	(1,251)
Balance at the end of the period	(1,846)	(1,846)	(3,501)	(2,250)
Estimated amount that will be amortized from accumulated other comprehensive loss into net periodic cost
Prior service cost/(gain)		(172)
Actuarial loss		97
Total		(75)
Weighted average assumptions used in determining the year-end benefit obligation
Discount rate (as a percent)	4.50%	4.50%	3.50%
Weighted average assumptions used to determine net periodic cost
Discount rate (as a percent)		3.50%	4.25%	5.50%