Commitments, Contingencies and Off-Balance Sheet Arrangements Commitments, Contingencies and Off Balance Sheet Arrangements - Legal Proceedings (Details) $ in Millions		1 Months Ended	4 Months Ended	9 Months Ended	12 Months Ended
	May 25, 2017 USD ($)	Aug. 31, 2014 case	Jun. 16, 2018 $ / d	Dec. 02, 2017	Feb. 28, 2015 USD ($)	Jun. 16, 2018 $ / yr
Other Commitments [Line Items]
Loss Contingency, Number of Plaintiffs			3
Litigation Settlement, Amount Awarded to Other Party	$ 9
Insurance Coverage Amount					$ 0
Insurance Claims Deductible Amount					$ 0
Judicial Ruling [Member]
Other Commitments [Line Items]
Loss Contingency, Number of Plaintiffs			5
Threatened Litigation [Member]
Other Commitments [Line Items]
Loss Contingency, Number of Plaintiffs				1
2014 Technology Intrusion [Member]
Other Commitments [Line Items]
Loss Contingency, New Claims Filed, Number | case		4
Office for Civil Rights of the U.S. Department of Health and Human Services Compliance Review [Member]
Other Commitments [Line Items]
Loss Contingency, Range of Possible Loss, Maximum, Per Unit			50,000			1,500,000.0