
	September 30, 2019		December 31, 2018
Materials and supplies	$	347.1	$	268.1
Prepaid taxes	59.2		35.0
Deferred costs	25.2		23.5
Prepaid expenses	17.3		15.2
Assets held-for-sale	8.9		—
Other	29.8		19.1
	$	487.5	$	360.9


	September 30, 2019		December 31, 2018
Right-of-use assets	$	64.9	$	—
Deferred tax assets	42.7		29.4
Tax receivables	36.6		8.4
Supplemental executive retirement plan assets	25.1		27.2
Intangible assets	13.4		2.5
Deferred costs	10.5		21.5
Other	11.6		8.8
	$	204.8	$	97.8


	September 30, 2019		December 31, 2018
Personnel costs	$	117.9	$	82.5
Accrued interest	99.0		100.6
Income and other taxes payable	65.3		36.9
Pension and other post-retirement benefits	34.1		—
Deferred revenue	24.6		56.9
Lease liabilities	23.4		—
Derivative liabilities	7.8		10.9
Accrued rig holding costs	7.2		14.3
Other	28.4		15.9
	$	407.7	$	318.0


	September 30, 2019		December 31, 2018
Unrecognized tax benefits (inclusive of interest and penalties)	$	313.5	$	177.0
Pension and other post-retirement benefits	194.5		—
Deferred tax liabilities	88.4		70.7
Lease liabilities	53.5		—
Intangible liabilities	52.7		53.5
Supplemental executive retirement plan liabilities	25.6		28.1
Personnel costs	21.0		25.1
Deferred revenue	11.7		20.5
Deferred rent	—		11.7
Other	37.3		9.4
	$	798.2	$	396.0

We are exposed to credit risk related to our receivables from customers, our cash and cash equivalents and our use of derivatives in connection with the management of foreign currency exchange rate risk. We mitigate our credit risk relating to receivables from customers, which consist primarily of major international, government-owned and independent oil and gas companies, by performing ongoing credit evaluations. We also maintain reserves for potential credit losses, which generally have been within our expectations. We mitigate our credit risk relating to cash and cash equivalents by focusing on diversification and quality of instruments. Cash equivalents consist of a portfolio of high-grade instruments. Custody of cash and cash equivalents is maintained at several well-capitalized financial institutions, and we monitor the financial condition of those financial institutions.

We mitigate our credit risk relating to derivative counterparties through a variety of techniques, including transacting with multiple, high-quality financial institutions, thereby limiting our exposure to individual counterparties and by entering into International Swaps and Derivatives Association, Inc. ("ISDA") Master Agreements, which include provisions for a legally enforceable master netting agreement, with almost all of our derivative counterparties. The terms of the ISDA agreements may also include credit support requirements, cross default provisions, termination events or set-off provisions. Legally enforceable master netting agreements reduce credit risk by providing protection in bankruptcy in certain circumstances and generally permitting the closeout and netting of transactions with the same counterparty upon the occurrence of certain events. See Note 5 for additional information on our derivatives.


	Three Months Ended September 30,						Nine Months Ended September 30,
	2019		2018		2019		2018
Saudi Aramco⁽¹⁾	16	%	11	%	12	%	10	%
Total⁽²⁾	15	%	14	%	15	%	14	%
BP⁽³⁾	10	%	5	%	8	%	7	%
INPEX⁽⁴⁾	7	%	10	%	7	%	7	%
Other	52	%	60	%	58	%	62	%
	84	%	89	%	88	%	90	%

⁽²⁾During the three-month and nine-month periods ended September 30, 2019, 90% and 93% of revenues provided by Total were attributable to the Floaters segment and the remainder was attributable to the Jackup segments. During the three-month and nine-month periods ended September 30, 2018, all revenues were attributable to the Floaters segment.

⁽³⁾During the three-month period ended September 30, 2019, 43% of the revenues provided by BP were attributable to our Jackups segment, 17% of the revenues were attributable to our Floaters segment and the remaining was attributable to our Other segment. During the three-month period ended September 30, 2018, 27% of the revenues provided by BP were attributable to our Jackups segment and the remainder was attributable to our Other segment.

During the nine-month period ended September 30, 2019, 41% of the revenues provided by BP were attributable to our Jackups segment, 16% of the revenues were attributable to our Floaters segment and the remainder was attributable to our Other segment. During the nine-month period ended September 30, 2018, 33% of the revenues provided by BP were attributable to our Floaters segment, 18% of the revenues were attributable to our Jackups segment and the remainder was attributable to our Other segment.


	Three Months Ended September 30,						Nine Months Ended September 30,
	2019		2018		2019		2018
Saudi Arabia⁽¹⁾	$	90.3	$	49.0	$	226.9	$	131.8
U.S. Gulf of Mexico⁽²⁾	83.1		59.3		231.2		172.4
Angola⁽³⁾	72.1		76.2		210.8		209.5
United Kingdom⁽⁴⁾	59.6		55.4		157.2		155.7
Australia⁽⁵⁾	51.6		75.1		189.0		207.7
Other	194.6		115.9		526.0		429.3
	$	551.3	$	430.9	$	1,541.1	$	1,306.4

⁽¹⁾During the three-month and nine-month periods ended September 30, 2019, 58% and 69% of the revenues earned in Saudi Arabia were attributable to our Jackups segment, respectively. The remaining revenues were attributable to our Other segment and related to our rigs leased to ARO and certain revenues related to our Transition Services Agreement and Secondment Agreement. During the three-month and nine-month periods ended September 30, 2018, all revenues earned in Saudi Arabia were attributable to our Jackups segment.

⁽²⁾During the three-month period ended September 30, 2019, 52% of the revenues earned in the U.S. Gulf of Mexico were attributable to our Floaters segment, 22% were attributable to our Jackups segment and the remaining revenues were attributable to our Other segment. During the three-month period ended September 30, 2018, 35% of the revenues earned in U.S. Gulf of Mexico were attributable to our Floaters segment, 39% were attributable to our Jackups segment and the remaining revenues were attributable to our Other segment.

During the nine-month period ended September 30, 2019, 40% of revenues in the U.S. Gulf of Mexico were attributable to our Floaters segment, 35% were attributable to our Jackups segment and the remaining revenues were attributable to our Other segment. During the nine-month period ended September 30, 2018, 36% of the revenues in the U.S. Gulf of Mexico were attributable to our Floaters segment, 38% were attributable to our Jackups segment and the remaining revenues were attributable to our Other segment.

⁽³⁾During the three-month periods ended September 30, 2019 and 2018, 86% and 82% of the revenues earned in Angola were attributable to our Floaters segment, respectively, and the remaining revenues were attributable to our Jackups segment. During the nine-month periods ended September 30, 2019 and 2018, 87% of the revenues earned in Angola were attributable to our Floaters segment and the remaining revenues were attributable to our Jackups segment.

⁽⁵⁾During the three-month periods ended September 30, 2019 and 2018, 99% and 87% of the revenues earned in Australia, were attributable to our Floaters segment, and the remaining revenues were attributable to our Jackups segment. During the nine-month periods ended September 30, 2019 and 2018, 95% and 94% of the revenues earned in Australia were attributable to our Floaters segment, respectively, and the remaining revenues were attributable to our Jackups segment.