Subsequent Events Accelerated Share Repurchases (Details) - Subsequent Event [Member]		1 Months Ended
	Oct. 02, 2018	Mar. 31, 2019	Feb. 28, 2019
Accelerated Share Repurchases [Line Items]
Accelerated Share Repurchase, Date Entered	Oct. 02, 2018
Minimum [Member]
Accelerated Share Repurchases [Line Items]
Accelerated Share Repurchase, Completion Date			2/1/2019
Maximum [Member]
Accelerated Share Repurchases [Line Items]
Accelerated Share Repurchase, Completion Date		3/1/2019