Description of Business and Summary of Significant Accounting Policies (Employee Savings Plans) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Matching contribution, 401(k) plan	$ 5.2	$ 3.5	$ 2.1
Balances due to participants	51.7	40.6
Employer matching contribution [Member]
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Matching contributions to employee participants	$ 0.5	$ 0.5	$ 0.6
Deferred compensation arrangement with individual matching contribution annual vesting years two and three	33.00%
Deferred compensation arrangement with individual matching contribution annual vesting portion, year one	33.00%
Employer discretionary contribution [Member]
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Employer contributions vesting periods (in years)	3 years
Employees Hired Subsequent to January 1, 2011 [Member]
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
401(k) plan matching contribution requisite service period	3 years