Debt (Schedule of Letters of Credit Facilities) (Details)	Sep. 30, 2019 USD ($)
Letter of Credit [Member]
Debt Instrument [Line Items]
Letters of credit, Limit	$ 208,700,000
Letters of credit, Used	47,700,000
Letters of credit, Available	161,000,000.0
Letter of Credit [Member] | Bi-lateral Facility [Member]
Debt Instrument [Line Items]
Letters of credit, Limit	25,000,000.0
Letters of credit, Used	11,500,000
Letters of credit, Available	13,500,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Letter of credit maximum sublimit	150,000,000
Letters of credit, Limit	1,000,000,000.0
Revolving Credit Facility [Member] | Letter of Credit [Member]
Debt Instrument [Line Items]
Letters of credit, Available	150,000,000.0
Accounts Receivable Securitization Facility [Member]
Debt Instrument [Line Items]
Letters of credit, Used	36,200,000
Accounts Receivable Securitization Facility [Member] | Letter of Credit [Member]
Debt Instrument [Line Items]
Letters of credit, Limit	33,700,000
Letters of credit, Used	36,200,000
Letters of credit, Available	$ (2,500,000)