Long-term Debt (Tables)

12 Months Ended

Dec. 31, 2015

Debt Disclosure [Abstract]

Schedule of Long-term Debt Instruments [Table Text Block]

			December 31,
Dollar amounts in millions	Interest Rate 2015		2015									2014
			Principal			Unamortized Debt Costs			Total			Principal			Unamortized Debt Costs			Total
Debentures:
Senior unsecured notes, maturing 2020, interest rates fixed	7.5	%	$	350.0		$	(3.7	)	$	346.3		$	350.0		$	(4.4	)	$	345.6
Bank credit facilities:
Chilean term credit facility, maturing 2019, interest rates fixed	UF+3.9%		12.8						12.8			14.4						14.4
Brazilian export financing facility, maturing 2017, interest rates fixed	6.65	%	4.0						4.0			6.0						6.0
Limited recourse notes payable:
Senior notes, payable 2018, interest rates fixed	7.3	%	22.0						22.0			22.0						22.0
Other financing:
Non-recourse notes payable 2018, interest rates variable	0.2	%	368.7			(0.2		)	368.5			368.7			(0.3		)	368.4
Other			0.3						0.3			0.8						0.8
Total			757.8			(3.9		)	753.9			761.9			(4.7		)	757.2
Less: current portion			(2.1		)				(2.1		)	(2.4		)				(2.4		)
Net long-term portion			$	755.7		$	(3.9	)	$	751.8		$	759.5		$	(4.7	)	$	754.8

Schedule of Maturities of Long-term Debt [Table Text Block]

The weighted average interest rate for all long-term debt at December 31, 2015 and 2014 was approximately 4.0 percent for both periods. Required repayment of principal for long-term debt is as follows:

Dollar amounts in millions
Year ended December 31,
2016	$	2.1
2017	6.4
2018	395.0
2019	4.3
2020	350.0
2021 and after	—
Total	$	757.8