Debt (Tables)

3 Months Ended

Mar. 31, 2014

Debt Disclosure [Abstract]

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

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

(Dollars in Millions)	Mar 31, 2014		Dec 31, 2013
Senior Notes:
6.00% Senior Notes due May 15, 2017	$	358.0	$	357.9
6.00% Senior Notes due November 30, 2015	249.2		249.0
7.375% Subordinated Debentures due February 27, 2054	144.2		—
Total Debt Outstanding	$	751.4	$	606.9

Schedule of Interest Expense [Table Text Block]

Interest Expense, including facility fees, accretion of discount and amortization of issuance costs, for the three months endedMarch 31, 2014 and 2013 was:

	Three Months Ended
(Dollars in Millions)	Mar 31, 2014			Mar 31, 2013
Notes Payable under Revolving Credit Agreement	$	0.2		$	0.3
Senior Notes Payable:
6.00% Senior Notes due May 15, 2017	5.5			5.5
6.00% Senior Notes due November 30, 2015	3.9			3.9
7.375% Subordinated Debentures due February 27, 2054	1.0			—
Mortgage Note Payable due September 1, 2013	—			0.1
Interest Expense before Capitalization of Interest	10.6			9.8
Capitalization of Interest	(0.3		)	(0.3		)
Total Interest Expense	$	10.3		$	9.5

Schedule of Interest Paid [Table Text Block]

Interest paid, including facility fees, for the three months endedMarch 31, 2014 and 2013 was:

	Three Months Ended
(Dollars in Millions)	Mar 31, 2014		Mar 31, 2013
Notes Payable under Revolving Credit Agreement	$	0.2	$	—
Mortgage Note Payable due September 1, 2013	—		0.1
Total Interest Paid	$	0.2	$	0.1