Long-Term Debt (Narrative) (Details) - USD ($) | May 22, 2018 | Sep. 30, 2019 | Sep. 30, 2018 |
Debt Instrument [Line Items] | | | |
Proceeds from revolving credit facilities | | $ 733,000,000 | $ 1,004,000,000 |
Global ABL Facility [Member] | | | |
Debt Instrument [Line Items] | | | |
Credit facility, maximum borrowing capacity | | 800,000,000 | |
Proceeds from revolving credit facilities | | 200,000,000 | |
Credit facility, remaining borrowing capacity | | 477,000,000 | |
Global ABL Facility [Member] | U.S. [Member] | | | |
Debt Instrument [Line Items] | | | |
Credit facility, maximum borrowing capacity | | 675,000,000 | |
Global ABL Facility [Member] | Canada [Member] | | | |
Debt Instrument [Line Items] | | | |
Credit facility, maximum borrowing capacity | | 65,000,000 | |
Global ABL Facility [Member] | United Kingdom [Member] | | | |
Debt Instrument [Line Items] | | | |
Credit facility, maximum borrowing capacity | | 7,000,000 | |
Global ABL Facility [Member] | Australia [Member] | | | |
Debt Instrument [Line Items] | | | |
Credit facility, maximum borrowing capacity | | 15,000,000 | |
Global ABL Facility [Member] | Belgium [Member] | | | |
Debt Instrument [Line Items] | | | |
Credit facility, maximum borrowing capacity | | 7,000,000 | |
Global ABL Facility [Member] | Norway [Member] | | | |
Debt Instrument [Line Items] | | | |
Credit facility, maximum borrowing capacity | | 18,000,000 | |
Global ABL Facility [Member] | Netherlands [Member] | | | |
Debt Instrument [Line Items] | | | |
Credit facility, maximum borrowing capacity | | $ 13,000,000 | |
Minimum [Member] | Senior Secured Term Loan B [Member] | Base Rate [Member] | | | |
Debt Instrument [Line Items] | | | |
Variable interest rate | | 2.00% | |
Minimum [Member] | Senior Secured Term Loan B [Member] | London Interbank Offered Rate (LIBOR) [Member] | | | |
Debt Instrument [Line Items] | | | |
Variable interest rate | | 1.00% | |
Minimum [Member] | Senior Secured Term Loan B, Refinanced [Member] | Base Rate [Member] | | | |
Debt Instrument [Line Items] | | | |
Variable interest rate | | 1.00% | |
Minimum [Member] | Senior Secured Term Loan B, Refinanced [Member] | London Interbank Offered Rate (LIBOR) [Member] | | | |
Debt Instrument [Line Items] | | | |
Variable interest rate | | 0.00% | |
Secured Term Loan [Member] | Senior Secured Term Loan B [Member] | | | |
Debt Instrument [Line Items] | | | |
Principal amount | | $ 400,000,000 | |
Term loan annual amortization percentage | | 1.00% | |
Term Loan accordion feature | | $ 200,000,000 | |
Percentage of capital stock in foreign subsidiaries securing Term Loan B | | 65.00% | |
Secured Term Loan [Member] | Senior Secured Term Loan B [Member] | Base Rate [Member] | | | |
Debt Instrument [Line Items] | | | |
Variable interest rate | 2.50% | | |
Secured Term Loan [Member] | Senior Secured Term Loan B [Member] | London Interbank Offered Rate (LIBOR) [Member] | | | |
Debt Instrument [Line Items] | | | |
Variable interest rate | 3.50% | | |
Secured Term Loan [Member] | Senior Secured Term Loan B, Refinanced [Member] | Base Rate [Member] | | | |
Debt Instrument [Line Items] | | | |
Variable interest rate | 2.00% | | |
Secured Term Loan [Member] | Senior Secured Term Loan B, Refinanced [Member] | London Interbank Offered Rate (LIBOR) [Member] | | | |
Debt Instrument [Line Items] | | | |
Variable interest rate | 3.00% | | |
Secured Term Loan [Member] | Senior Secured Leverage Ratio Is No More Than 2.75 to 1.00 [Member] | Senior Secured Term Loan B [Member] | | | |
Debt Instrument [Line Items] | | | |
Senior secured leverage ratio | | 2.75 | |
Repayment of Term Loan, percentage | | 25.00% | |
Secured Term Loan [Member] | Senior Secured Leverage Ratio Is No More Than 2.50 to 1.00 [Member] | Senior Secured Term Loan B [Member] | | | |
Debt Instrument [Line Items] | | | |
Senior secured leverage ratio | | 2.50 | |
Repayment of Term Loan, percentage | | 0.00% | |
Secured Term Loan [Member] | Maximum [Member] | Senior Secured Term Loan B [Member] | | | |
Debt Instrument [Line Items] | | | |
Senior secured leverage ratio | | 4 | |
Repayment of Term Loan, percentage | | 50.00% | |