Debt (Tables)

9 Months Ended

Sep. 30, 2014

Debt Disclosure [Abstract]

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

The amortized cost of debt outstanding at September 30, 2014 and December 31, 2013 was:

(Dollars in Millions)	Sep 30, 2014		Dec 31, 2013
Senior Notes:
6.00% Senior Notes due November 30, 2015	$	249.4	$	249.0
6.00% Senior Notes due May 15, 2017	358.3		357.9
7.375% Subordinated Debentures due February 27, 2054	144.2		—
Total Debt Outstanding	$	751.9	$	606.9

Schedule of Interest Expense [Table Text Block]

Interest Expense, including facility fees, accretion of discount and amortization of issuance costs, for the nine and three months endedSeptember 30, 2014 and 2013 was:

	Nine Months Ended						Three Months Ended
(Dollars in Millions)	Sep 30, 2014			Sep 30, 2013			Sep 30, 2014			Sep 30, 2013
Notes Payable under Revolving Credit Agreement	$	0.6		$	0.9		$	0.2		$	0.3
Senior Notes Payable:
6.00% Senior Notes due November 30, 2015	11.6			11.6			3.9			3.9
6.00% Senior Notes due May 15, 2017	16.6			16.6			5.5			5.5
7.375% Subordinated Debentures due February 27, 2054	6.6			—			2.8			—
Mortgage Note Payable	—			0.2			—			—
Interest Expense before Capitalization of Interest	35.4			29.3			12.4			9.7
Capitalization of Interest	(0.8		)	(0.7		)	(0.3		)	(0.2		)
Total Interest Expense	$	34.6		$	28.6		$	12.1		$	9.5

Schedule of Interest Paid [Table Text Block]

Interest paid, including facility fees, for the nine and three months endedSeptember 30, 2014 and 2013 was:

	Nine Months Ended				Three Months Ended
(Dollars in Millions)	Sep 30, 2014		Sep 30, 2013		Sep 30, 2014		Sep 30, 2013
Notes Payable under Revolving Credit Agreement	$	0.5	$	0.6	$	0.2	$	0.4
Senior Notes Payable:
6.00% Senior Notes due November 30, 2015	7.5		7.5		—		—
6.00% Senior Notes due May 15, 2017	10.8		10.8		—		—
7.375% Subordinated Debentures due February 27, 2054	5.5		—		2.7		—
Mortgage Note Payable	—		0.3		—		0.1
Total Interest Paid	$	24.3	$	19.2	$	2.9	$	0.5