Earnings Per Share and Common Stock (Tables)

6 Months Ended

Jun. 30, 2019

Earnings Per Share [Abstract]

Reconciliation of Basic and Diluted Earnings Per Share [Table Text Block]

			2019					2018
Reconciliation of Basic and Diluted			Dilutive					Dilutive
Earnings Per Share	Basic		Securities	Diluted		Basic		Securities	Diluted
Millions Except Per Share Amounts
Quarter ended June 30,
Net Income		$34.2			$34.2		$31.3			$31.3
Average Common Shares	51.6		0.1	51.7		51.3		0.2	51.5
Earnings Per Share		$0.66			$0.66		$0.61			$0.61
Six Months Ended June 30,
Net Income		$104.7			$104.7		$82.3			$82.3
Average Common Shares	51.6		0.1	51.7		51.2		0.2	51.4
Earnings Per Share		$2.03			$2.02		$1.61			$1.60