Long-term Debt	9 Months Ended
Jun. 30, 2017
Debt Disclosure [Abstract]
Long-term Debt	Long-term Debt Jacobs and certain of its subsidiaries have a $1.6 billion long-term unsecured, revolving credit facility (the “2014 Facility”) with a syndicate of large U.S. and international banks and financial institutions. The 2014 Facility provides an accordion feature that allows the Company and the lenders to increase the facility amount to $2.1 billion. The total amount outstanding under the 2014 Facility in the form of direct borrowings at June 30, 2017 was $282.0 million. The Company has issued $2.5 million in letters of credit under the 2014 Facility, leaving $1.3 billion of available borrowing capacity under the 2014 Facility at June 30, 2017. In addition, the Company had issued $35.8 million under separate, committed and uncommitted letter-of-credit facilities for total issued letters of credit of $38.3 million at June 30, 2017. The 2014 Facility expires in February 2020 and permits the Company to borrow under two separate tranches in U.S. dollars, certain specified foreign currencies, and any other currency that may be approved in accordance with the terms of the 2014 Facility. Depending on the Company’s Consolidated Leverage Ratio (as defined in the credit agreement governing the 2014 Facility), borrowings under the 2014 Facility bear interest at either a eurocurrency rate plus a margin of between 1.0% and 1.5% or a base rate plus a margin of between 0% and 0.5%. The 2014 Facility also provides for a financial letter of credit sub facility of $300.0 million, permits performance letters of credit, and provides for a $50.0 million sub facility for swing line loans. Letters of credit are subject to fees based on the Company’s Consolidated Leverage Ratio at the time any such letter of credit is issued. The Company pays a facility fee of between 0.100% and 0.250% per annum depending on the Company’s Consolidated Leverage Ratio. Amounts outstanding under the 2014 Facility may be prepaid at the option of the Company without premium or penalty, subject to customary breakage fees in connection with the prepayment of euro currency loans. The 2014 Facility contains affirmative, negative, and financial covenants customary for financings of this type including, among other things, limitations on certain other indebtedness, loans and investments, liens, mergers, asset sales and transactions with affiliates. In addition, the 2014 Facility contains customary events of default. We were in compliance with our debt covenants at June 30, 2017.

Long-term Debt

Jacobs and certain of its subsidiaries have a $1.6 billion long-term unsecured, revolving credit facility (the “2014 Facility”) with a syndicate of large U.S. and international banks and financial institutions. The 2014 Facility provides an accordion feature that allows the Company and the lenders to increase the facility amount to $2.1 billion.

The total amount outstanding under the 2014 Facility in the form of direct borrowings at June 30, 2017 was $282.0 million. The Company has issued $2.5 million in letters of credit under the 2014 Facility, leaving $1.3 billion of available borrowing capacity under the 2014 Facility at June 30, 2017. In addition, the Company had issued $35.8 million under separate, committed and uncommitted letter-of-credit facilities for total issued letters of credit of $38.3 million at June 30, 2017.

The 2014 Facility expires in February 2020 and permits the Company to borrow under two separate tranches in U.S. dollars, certain specified foreign currencies, and any other currency that may be approved in accordance with the terms of the 2014 Facility. Depending on the Company’s Consolidated Leverage Ratio (as defined in the credit agreement governing the 2014 Facility), borrowings under the 2014 Facility bear interest at either a eurocurrency rate plus a margin of between 1.0% and 1.5% or a base rate plus a margin of between 0% and 0.5%. The 2014 Facility also provides for a financial letter of credit sub facility of $300.0 million, permits performance letters of credit, and provides for a $50.0 million sub facility for swing line loans. Letters of credit are subject to fees based on the Company’s Consolidated Leverage Ratio at the time any such letter of credit is issued. The Company pays a facility fee of between 0.100% and 0.250% per annum depending on the Company’s Consolidated Leverage Ratio. Amounts outstanding under the 2014 Facility may be prepaid at the option of the Company without premium or penalty, subject to customary breakage fees in connection with the prepayment of euro currency loans. The 2014 Facility contains affirmative, negative, and financial covenants customary for financings of this type including, among other things, limitations on certain other indebtedness, loans and investments, liens, mergers, asset sales and transactions with affiliates. In addition, the 2014 Facility contains customary events of default. We were in compliance with our debt covenants at June 30, 2017.