Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash flows from operating activities:
Net income (loss)	$ (56.9)	$ (1,474.6)
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Depreciation and amortization	111.8	110.8
Stock-based compensation	6.4	8.3
Change in fair value of catalyst obligations	10.0	(11.7)
Deferred income taxes	(9.4)	14.2
Non-cash change in inventory repurchase obligations	8.0	(67.9)
Non-cash lower of cost or market inventory adjustment	(405.6)	1,285.6
Change in fair value of contingent consideration	29.5	(53.0)
Debt extinguishment costs	0.0	22.2
Pension and other post-retirement benefit costs	12.8	13.1
Gain on sale of assets	(0.6)	0.0
Changes in operating assets and liabilities:
Accounts receivable	(358.0)	394.7
Due to/from affiliates	5.1	32.0
Inventories	(220.6)	74.3
Prepaid and other current assets	(79.6)	(44.8)
Accounts payable	291.0	(198.7)
Accrued expenses	638.1	(367.0)
Deferred revenue	(25.8)	16.9
Other assets and liabilities	(23.8)	(9.0)
Net cash used in operating activities	(67.6)	(254.6)
Cash flows from investing activities:
Expenditures for property, plant and equipment	(36.1)	(59.2)
Expenditures for deferred turnaround costs	(16.8)	(69.1)
Expenditures for other assets	(6.3)	(4.6)
Acquisition of Martinez refinery	0.0	(1,176.2)
Net cash used in investing activities	(59.2)	(1,309.1)
Cash flows from financing activities:
Contributions from PBF LLC	10.0	0.0
Distributions to members	(1.0)	(21.1)
Proceeds from revolver borrowings	0.0	1,150.0
Repayments of revolver borrowings	0.0	(250.0)
Payments on financing leases	(3.5)	(2.6)
Proceeds from insurance premium financing	48.9	45.3
Deferred financing costs and other	0.5	(12.3)
Net cash provided by financing activities	53.1	1,390.0
Net decrease in cash and cash equivalents	(73.7)	(173.7)
Cash and cash equivalents, beginning of period	1,570.1	763.1
Cash and cash equivalents, end of period	1,496.4	589.4
Non-cash activities:
Accrued and unpaid capital expenditures	42.2	125.2
Assets acquired or remeasured under operating and financing leases	(152.8)	111.1
Fair value of the Martinez Contingent Consideration at acquisition	0.0	77.3
Cash paid during the period for:
Interest (net of capitalized interest of $2.2 million and $3.3 million in 2021 and 2020, respectively)	38.9	13.4
Income taxes	0.1	0.0
Capitalized interest	2.2	3.3
2028 Senior Notes [Member]
Cash flows from financing activities:
Proceeds from Issuance of Long-term Debt	0.0	1,000.0
2023 Senior Notes [Member]
Cash flows from financing activities:
Repayments of Long-term Debt	0.0	(517.5)
Rail Term Loan [Member]
Cash flows from financing activities:
Repayments of Long-term Debt	$ (1.8)	$ (1.8)