Shareholder's Equity (Schedule of Stock Option Activity - Additional) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Equity [Abstract]
Total intrinsic value with options exercised	$ 4.9	$ 2.6	$ 33.3
Aggregate intrinsic value of options outstanding	1.8
Total intrinsic value of options vested or expected to vest	$ 1.8
Vested or expected to vest at end of period, Number of Shares	33,751
Vested or expected to vest at end of period, weighted average exercise price (usd per share)	$ 22.98
Vested or expected to vest at end of period, Weighted Average Remaining Contractual Life (in years)	1 year 36 days
Total Intrinsic value of options exercisable	$ 1.8
Exercisable at end of period, Number of Shares	33,751
Exercisable at end of period, Weighted Average Exercise Price (usd per share)	$ 22.98
Exercisable at end of period, Weighted Average Remaining Contractual Life (in years)	1 year 36 days