Share-Based Compensation Plans: Schedule of Share-Based Compensation Expense (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Employee savings plan (See Note 7)	$ 5.6	$ 7.2
Executive and management incentive compensation plans	4.2	0
Share-based compensation expense	14.8	13.7
Restricted Stock and Restricted Stock Units [Member] | Common Stock and Additional Paid-In Capital
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Restricted stock and restricted units	$ 5.0	$ 6.5