Valaris Limited (VAL) 10-K 21 Feb 20 2019 FY Annual report Financial data

Document And Entity Information

Document And Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2019	Feb. 17, 2020	Jun. 30, 2019
Entity Information [Line Items]
Document Transition Report	false
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2019
Entity File Number	1-8097
Entity Registrant Name	Valaris plc
Entity Incorporation, State or Country Code	X0
Entity Tax Identification Number	98-0635229
Entity Address, Address Line One	110 Cannon Street
Entity Address, City or Town	London
Entity Address, Country	GB
Entity Address, Postal Zip Code	EC4N6EU
City Area Code	+44 (0)
Local Phone Number	20 7659 4660
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 21,353,000
Entity Common Shares, Shares Outstanding		197,280,817
Entity Shell Company	false
Amendment Flag	false
Entity Central Index Key	0000314808
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Entity Emerging Growth Company	false
Entity Small Business	false
Four Point Five Zero Percent Senior Notes Due Two Thousand Twenty Four [Member]
Entity Information [Line Items]
Title of 12(b) Security	4.50% Senior Notes due 2024
Security Exchange Name	NYSE
Trading Symbol	VAL24
Eight Point Zero Percent Senior Notes Due Two Thousand Twenty Four [Member]
Entity Information [Line Items]
Title of 12(b) Security	8.00% Senior Notes due 2024
Security Exchange Name	NYSE
Trading Symbol	VAL24A
Five Point Two Percent Senior Notes [Member]
Entity Information [Line Items]
Title of 12(b) Security	5.20% Senior Notes due 2025
Security Exchange Name	NYSE
Trading Symbol	VAL25A
7.75% Senior notes due 2026
Entity Information [Line Items]
Title of 12(b) Security	7.75% Senior Notes due 2026
Security Exchange Name	NYSE
Trading Symbol	VAL26
5.75% Senior notes due 2044
Entity Information [Line Items]
Title of 12(b) Security	5.75% Senior Notes due 2044
Security Exchange Name	NYSE
Trading Symbol	VAL44
4.70% Senior notes due 2021
Entity Information [Line Items]
Title of 12(b) Security	4.70% Senior Notes due 2021
Security Exchange Name	NYSE
Trading Symbol	VAL21
Class A Ordinary Shares, US 0.40 Par Value [Member]
Entity Information [Line Items]
Title of 12(b) Security	Class A ordinary shares, U.S. $0.40 par value
Security Exchange Name	NYSE
Trading Symbol	VAL

Consolidated Statements Of Oper

Consolidated Statements Of Operations - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Statement [Abstract]
OPERATING REVENUES	$ 2,053.2	$ 1,705.4	$ 1,843
OPERATING EXPENSES
Cost of Goods and Services Sold	1,806	1,319.4	1,189.5
Loss on impairment	104	40.3	182.9
Depreciation	609.7	478.9	444.8
General and administrative	188.9	102.7	157.8
Total operating expenses	2,708.6	1,941.3	1,975
EQUITY IN EARNINGS OF ARO	(12.6)	0	0
OPERATING LOSS	(668)	(235.9)	(132)
OTHER INCOME (EXPENSE)
Interest income	28.1	14.5	25.8
Interest expense, net	(428.3)	(282.7)	(224.2)
Other, net	1,004.4	(34.8)	134.4
Other income (expense), net	604.2	(303)	(64)
LOSS FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	(63.8)	(538.9)	(196)
PROVISION FOR INCOME TAXES
Current income tax expense	104.5	33	54.2
Deferred income tax expense (benefit)	23.9	56.6	55
Total provision for income taxes	128.4	89.6	109.2
LOSS FROM CONTINUING OPERATIONS	(192.2)	(628.5)	(305.2)
INCOME (LOSS) FROM DISCONTINUED OPERATIONS, NET	0	(8.1)	1
NET LOSS	(192.2)	(636.6)	(304.2)
NET (INCOME) LOSS ATTRIBUTABLE TO NONCONTROLLING INTERESTS	(5.8)	(3.1)	0.5
NET LOSS ATTRIBUTABLE TO VALARIS	$ (198)	$ (639.7)	$ (303.7)
LOSS PER SHARE - BASIC AND DILUTED
Continuing operations	$ (1.14)	$ (5.82)	$ (3.66)
Discontinued operations	0	(0.08)	0
Total earnings per share - basic	$ (1.14)	$ (5.90)	$ (3.66)
WEIGHTED-AVERAGE SHARES OUTSTANDING
Basic and Diluted	173.4	108.5	83.1

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
NET LOSS	$ (214)	$ (197.5)	$ 407.3	$ (188)	$ (203.1)	$ (142.9)	$ (150.1)	$ (140.5)	$ (192.2)	$ (636.6)	$ (304.2)
OTHER COMPREHENSIVE INCOME (LOSS), NET
Increase (Decrease) in Obligation, Pension and Other Postretirement Benefits									(21.7)	0	0
Net change in fair value of derivatives									1.6	(9.7)	8.5
Reclassification of net (gains) losses on derivative instruments from other comprehensive income (loss) into net loss									8.3	(1)	0.4
Other									(0.2)	(0.5)	0.7
NET OTHER COMPREHENSIVE INCOME (LOSS)									(12)	(11.2)	9.6
COMPREHENSIVE LOSS									(204.2)	(647.8)	(294.6)
COMPREHENSIVE INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS									(5.8)	(3.1)	0.5
COMPREHENSIVE LOSS ATTRIBUTABLE TO VALARIS									$ (210)	$ (650.9)	$ (294.1)

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
CURRENT ASSETS
Cash and cash equivalents	$ 97.2	$ 275.1
Short-term Investments	0	329
Accounts receivable, net	520.7	344.7
Other	446.5	360.9
Total current assets	1,064.4	1,309.7
PROPERTY AND EQUIPMENT, AT COST	18,393.8	15,517
Less accumulated depreciation	3,296.9	2,900.8
Property and equipment, net	15,096.9	12,616.2
LONG-TERM NOTES RECEIVABLE FROM ARO	452.9	0
INVESTMENT IN ARO	128.7	0
OTHER ASSETS	188.3	97.8
TOTAL ASSETS	16,931.2	14,023.7
CURRENT LIABILITIES
Accounts payable - trade	288.2	210.5
Accrued liabilities and other	417.7	318
Current maturities of long-term debt	124.8	0
Total current liabilities	830.7	528.5
LONG-TERM DEBT	5,923.5	5,010.4
OTHER LIABILITIES	867.4	396
COMMITMENTS AND CONTINGENCIES
ENSCO SHAREHOLDERS' EQUITY
Additional paid-in capital	8,627.8	7,225
Retained earnings	671.7	874.2
Accumulated other comprehensive income	6.2	18.2
Treasury shares, at cost, 7.9 million and 5.9 million shares as of December 31, 2019 and 2018	(77.3)	(72.2)
Total Valaris shareholders' equity	9,310.9	8,091.4
NONCONTROLLING INTERESTS	(1.3)	(2.6)
Total equity	9,309.6	8,088.8
Total liabilities and shareholders' equity	16,931.2	14,023.7
Class A Ordinary Shares, U.S. [Member]
ENSCO SHAREHOLDERS' EQUITY
Common shares, value	82.4	46.1
Common Class B, Par Value In GBP [Member]
ENSCO SHAREHOLDERS' EQUITY
Common shares, value	$ 0.1	$ 0.1

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical)	Dec. 31, 2019£ / sharesshares	Dec. 31, 2019$ / sharesshares	Dec. 31, 2018£ / sharesshares	Dec. 31, 2018$ / sharesshares
Treasury shares, shares held	7,900,000	7,900,000	5,900,000	5,900,000
Class A Ordinary Shares, U.S. [Member]
Common shares, par value | $ / shares		$ 0.40		$ 0.40
Common shares, shares issued	205,900,000	205,900,000	115,200,000	115,200,000
Common Class B, Par Value In GBP [Member]
Common shares, par value | £ / shares	£ 1		£ 1
Common shares, shares issued	50,000	50,000	50,000	50,000

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
OPERATING ACTIVITIES
Net loss	$ (192.2)	$ (636.6)	$ (304.2)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities of continuing operations:
Bargain purchase gain	(637)	(1.8)	(140.2)
Depreciation expense	609.7	478.9	444.8
(Gain) loss on debt extinguishment	(194.1)	19	2.6
Loss on impairment	104	40.3	182.9
Share-based compensation expense	37.3	29.9	34.2
Amortization, net	(16.8)	(40.2)	(61.6)
Equity in earnings of ARO	12.6	0	0
Deferred income tax expense	23.9	56.6	55
Other	16.8	4.5	(26.5)
Changes in operating assets and liabilities, net of acquisition	(27.9)	(6.3)	72.4
Contributions to pension plans and other post-retirement benefits	(13.2)	0	0
Net cash provided by operating activities of continuing operations	(276.9)	(55.7)	259.4
INVESTING ACTIVITIES
Acquisition of Rowan, net of cash acquired	931.9	0	0
Maturities of short-term investments	474	1,030	2,042.5
Purchases of short-term investments	(145)	(919)	(1,040)
Additions to property and equipment	(227)	(426.7)	(536.7)
Net proceeds from disposition of assets	17.7	11	2.8
Acquisition of Atwood, net of cash acquired	0	0	(871.6)
Net cash used in investing activities of continuing operations	1,051.6	(304.7)	(403)
FINANCING ACTIVITIES
Reduction of long-term borrowings	(928.1)	(771.2)	(537)
Borrowings on credit facility	215	0	0
Repayments of credit facility borrowings	(215)	0	0
Debt solicitation fees	(9.5)	0	0
Cash dividends paid	(4.5)	(17.9)	(13.8)
Proceeds from issuance of senior notes	0	1,000	0
Debt issuance costs	0	(17)	(12)
Other	(10.2)	(5.7)	(7.7)
Net cash provided by (used in) financing activities	(952.3)	188.2	(570.5)
Net cash provided by (used in) discontinued operations	0	2.5	(0.8)
Effect of exchange rate changes on cash and cash equivalents	(0.3)	(0.6)	0.6
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	(177.9)	(170.3)	(714.3)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	275.1	445.4	1,159.7
CASH AND CASH EQUIVALENTS, END OF YEAR	$ 97.2	$ 275.1	$ 445.4

Description Of The Business And

Description Of The Business And Summary Of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Description Of The Business And Summary Of Significant Accounting Policies	DESCRIPTION OF THE BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Business We are a leading provider of offshore contract drilling services to the international oil and gas industry. Exclusive of two rigs under construction and one rigs marked for retirement and classified as held-for-sale, we currently own and operate an offshore drilling rig fleet of 74 rigs, with drilling operations in almost every major offshore market across six continents. Inclusive of our rigs under construction, our fleet includes 16 drillships, eight dynamically positioned semisubmersible rigs, two moored semisubmersible rigs and 50 jackup rigs, nine of which are leased to our 50/50 joint venture with Saudi Aramco. We operate the world's largest fleet amongst competitive rigs, including one of the newest ultra-deepwater fleets in the industry and a leading premium jackup fleet. Our customers include many of the leading national and international oil companies, in addition to many independent operators. We are among the most geographically diverse offshore drilling companies, with current operations spanning 24 countries on six continents. The markets in which we operate include the Gulf of Mexico, Brazil, the Mediterranean, the North Sea, Norway, the Middle East, West Africa, Australia and Southeast Asia. We provide drilling services on a day rate contract basis. Under day rate contracts, we provide an integrated service that includes the provision of a drilling rig and rig crews for which we receive a daily rate that may vary between the full rate and zero rate throughout the duration of the contractual term, depending on the operations of the rig. We also may receive lump-sum fees or similar compensation for the mobilization, demobilization and capital upgrades of our rigs. Our customers bear substantially all of the costs of constructing the well and supporting drilling operations, as well as the economic risk relative to the success of the well. Rowan Transaction On October 7, 2018 , we entered into a transaction agreement (the "Transaction Agreement") with Rowan Companies Limited (formerly Rowan Companies plc ("Rowan")) and on April 11, 2019 (the "Transaction Date"), we completed our combination with Rowan pursuant to the Transaction Agreement (the "Rowan Transaction") and changed our name to Ensco Rowan plc. On July 30, 2019 , we changed our name to Valaris plc. Rowan's financial results are included in our consolidated results beginning on the Transaction Date. As a result of the Rowan Transaction, Rowan shareholders received 2.750 Valaris Class A ordinary shares for each Rowan Class A ordinary share, representing a value of $43.67 per Rowan share based on a closing price of $15.88 per Valaris share on April 10, 2019 , the last trading day before the Transaction Date. Total consideration delivered in the Rowan Transaction consisted of 88.3 million Valaris shares with an aggregate value of $1.4 billion . All share and per share data included in this report have been retroactively adjusted to reflect the Reverse Stock Split (as defined herein). Prior to the Rowan Transaction, Rowan and Saudi Aramco formed a 50/50 joint venture to own, manage and operate drilling rigs offshore Saudi Arabia ("Saudi Aramco Rowan Offshore Drilling Company" or "ARO"). ARO currently owns a fleet of seven jackup rigs, leases another nine jackup rigs from us and has plans to purchase up to 20 newbuild jackup rigs over an approximate 10 year period. In January 2020, ARO ordered the first two newbuild jackups scheduled for delivery in 2022. The rigs we lease to ARO are done so through bareboat charter agreements whereby substantially all operating costs are incurred by ARO. All nine jackup rigs leased to ARO are under three-year contracts with Saudi Aramco. All seven ARO-owned jackup rigs are under long-term contracts with Saudi Aramco. The Rowan Transaction enhanced the market leadership of the combined company with a fleet of high-specification floaters and jackups and positions us well to meet increasing and evolving customer demand. The increased scale, diversification and financial strength of the combined company provides us advantages to better serve our customers. Exclusive of two older jackup rigs marked for retirement, Rowan’s offshore rig fleet at the Transaction Date consisted of four ultra-deepwater drillships and 19 jackup rigs. Reverse Stock Split Upon closing of the Rowan Transaction, we effected a consolidation (being a reverse stock split under English law) where every four existing Class A ordinary shares, each with a nominal value of $0.10 , were consolidated into one Class A ordinary share, each with a nominal value of $0.40 (the "Reverse Stock Split"). All share and per share data included in this report have been retroactively adjusted to reflect the Reverse Stock Split. Basis of Presentation—U.K. Companies Act 2006 Section 435 Statement The accompanying consolidated financial statements have been prepared in accordance with U.S. GAAP, which the Board of Directors consider to be the most meaningful presentation of our results of operations and financial position. The accompanying consolidated financial statements do not constitute U.K. statutory accounts for the year ended December 31, 2019 and 2018 as required to be prepared under the U.K. Companies Act 2006. The U.K. statutory accounts are prepared in accordance with Financial Reporting Standard 102, the financial reporting standard applicable in the U.K. and Republic of Ireland (“FRS 102”). The auditor has reported on the U.K. statutory accounts for the year ended December 31, 2018; their report was (i) unqualified, (ii) did not include a reference to any matters to which the auditor drew attention by way of emphasis without qualifying their report and (iii) did not contain a statement under section 498 (2) or (3) of the U.K. Companies Act 2006. The U.K. statutory accounts for the year ended December 31, 2019 have yet to be finalized and will be delivered to the U.K. registrar of companies during 2020. Principles of Consolidation The accompanying consolidated financial statements include the accounts of Valaris plc, those of our wholly-owned subsidiaries and entities in which we hold a controlling financial interest. All intercompany accounts and transactions have been eliminated. Investments in operating entities in which we have the ability to exercise significant influence, but where we do not control operating and financial policies are accounted for using the equity method. Significant influence generally exists if we have an ownership interest representing between 20% and 50% of the voting stock of the investee. We account for our interest in ARO using the equity method of accounting and only recognize our portion of equity in earnings in our consolidated financial statements. ARO is a variable interest entity; however, we are not the primary beneficiary and therefore do not consolidate ARO. Pervasiveness of Estimates The preparation of financial statements in conformity with U.S. GAAP requires us to make certain estimates, judgments and assumptions that affect the reported amounts of assets and liabilities, the related revenues and expenses and disclosures of gain and loss contingencies as of the date of the financial statements. Actual results could differ from those estimates. Foreign Currency Remeasurement and Translation Our functional currency is the U.S. dollar. As is customary in the oil and gas industry, a majority of our revenues and expenses are denominated in U.S. dollars; however, a portion of the revenues earned and expenses incurred by certain of our subsidiaries are denominated in currencies other than the U.S. dollar. These transactions are remeasured in U.S. dollars based on a combination of both current and historical exchange rates. Most transaction gains and losses, including certain gains and losses on our derivative instruments, are included in other, net, in our consolidated statement of operations. Certain gains and losses from the translation of foreign currency balances of our non-U.S. dollar functional currency subsidiaries are included in accumulated other comprehensive income on our consolidated balance sheet. Net foreign currency exchange losses, inclusive of offsetting fair value derivatives, were $7.4 million , $17.2 million and $5.1 million , and were included in other, net, in our consolidated statements of operations for the years ended December 31, 2019, 2018 and 2017 , respectively. Cash Equivalents and Short-Term Investments Highly liquid investments with maturities of three months or less at the date of purchase are considered cash equivalents. Highly liquid investments with maturities of greater than three months but less than one year at the date of purchase are classified as short-term investments. Short-term investments consisted of time deposits with initial maturities in excess of three months but less than one year and totaled $329.0 million as of December 31, 2018 . There were no short-term investments as of December 31, 2019 . Cash flows from purchases and maturities of short-term investments were classified as investing activities in our consolidated statements of cash flows for the years ended December 31, 2019, 2018 and 2017 . To mitigate our credit risk, our investments in time deposits are diversified across multiple, high-quality financial institutions. Property and Equipment All costs incurred in connection with the acquisition, construction, major enhancement and improvement of assets are capitalized, including allocations of interest incurred during periods that our drilling rigs are under construction or undergoing major enhancements and improvements. Costs incurred to place an asset into service are capitalized, including costs related to the initial mobilization of a newbuild drilling rig. Repair and maintenance costs are charged to contract drilling expense in the period in which they are incurred. Upon the sale or retirement of assets, the related cost and accumulated depreciation are removed from the balance sheet, and the resulting gain or loss is included in contract drilling expense. Our property and equipment is depreciated on a straight-line basis, after allowing for salvage values, over the estimated useful lives of our assets. Drilling rigs and related equipment are depreciated over estimated useful lives ranging from four to 35 years . Buildings and improvements are depreciated over estimated useful lives ranging from seven to 30 years . Other equipment, including computer and communications hardware and software costs, is depreciated over estimated useful lives ranging from three to six years . We evaluate the carrying value of our property and equipment for impairment when events or changes in circumstances indicate that the carrying value of such assets may not be recoverable. For property and equipment used in our operations, recoverability generally is determined by comparing the carrying value of an asset to the expected undiscounted future cash flows of the asset. If the carrying value of an asset is not recoverable, the amount of impairment loss is measured as the difference between the carrying value of the asset and its estimated fair value. Property and equipment held-for-sale is recorded at the lower of net book value or fair value less cost to sell. We recorded pre-tax, non-cash impairment losses related to long-lived assets of $104.0 million , $40.3 million and $182.9 million during 2019 , 2018 and 2017 , respectively. See "Note 6 - Property and Equipment" for additional information on our impairment charges. If the global economy deteriorates and/or our expectations relative to future offshore drilling industry conditions decline, it is reasonably possible that additional impairment charges may occur with respect to specific individual rigs, groups of rigs, such as a specific type of drilling rig, or rigs in a certain geographic location. Operating Revenues and Expenses See " Note 2 - Revenue from Contracts with Customers" for information on our accounting policies for revenue recognition and certain operating costs that are deferred and amortized over future periods. Derivative Instruments We use derivatives to reduce our exposure to various market risks, primarily foreign currency exchange rate risk. See " Note 8 - Derivative Instruments" for additional information on how and why we use derivatives. All derivatives are recorded on our consolidated balance sheet at fair value. Derivatives subject to legally enforceable master netting agreements are not offset on our consolidated balance sheet. Accounting for the gains and losses resulting from changes in the fair value of derivatives depends on the use of the derivative and whether it qualifies for hedge accounting. Derivatives qualify for hedge accounting when they are formally designated as hedges and are effective in reducing the risk exposure that they are designated to hedge. Changes in the fair value of derivatives that are designated as hedges of the variability in expected future cash flows associated with existing recognized assets or liabilities or forecasted transactions ("cash flow hedges") are recorded in accumulated other comprehensive income ("AOCI"). Amounts recorded in AOCI associated with cash flow hedges are subsequently reclassified into contract drilling, depreciation or interest expense as earnings are affected by the underlying hedged forecasted transactions. Gains and losses on a cash flow hedge, or a portion of a cash flow hedge, that no longer qualifies as effective due to an unanticipated change in the forecasted transaction are recognized currently in earnings and included in other, net, in our consolidated statement of operations based on the change in the fair value of the derivative. When a forecasted transaction becomes probable of not occurring, gains and losses on the derivative previously recorded in AOCI are reclassified currently into earnings and included in other, net, in our consolidated statement of operations. We occasionally enter into derivatives that hedge the fair value of recognized assets or liabilities but do not designate such derivatives as hedges or the derivatives otherwise do not qualify for hedge accounting. In these situations, a natural hedging relationship generally exists where changes in the fair value of the derivatives offset changes in the fair value of the underlying hedged items. Changes in the fair value of these derivatives are recognized currently in earnings in other, net, in our consolidated statement of operations. Derivatives with asset fair values are reported in other current assets or other assets, net, on our consolidated balance sheet depending on maturity date. Derivatives with liability fair values are reported in accrued liabilities and other, or other liabilities on our consolidated balance sheet depending on maturity date. Income Taxes We conduct operations and earn income in numerous countries. Current income taxes are recognized for the amount of taxes payable or refundable based on the laws and income tax rates in the taxing jurisdictions in which operations are conducted and income is earned. Deferred tax assets and liabilities are recognized for the anticipated future tax effects of temporary differences between the financial statement basis and the tax basis of our assets and liabilities using the enacted tax rates in effect at year-end. A valuation allowance for deferred tax assets is recorded when it is more-likely-than-not that the benefit from the deferred tax asset will not be realized. We do not offset deferred tax assets and deferred tax liabilities attributable to different tax paying jurisdictions. We operate in certain jurisdictions where tax laws relating to the offshore drilling industry are not well developed and change frequently. Furthermore, we may enter into transactions with affiliates or employ other tax planning strategies that generally are subject to complex tax regulations. As a result of the foregoing, the tax liabilities and assets we recognize in our financial statements may differ from the tax positions taken, or expected to be taken, in our tax returns. Our tax positions are evaluated for recognition using a more-likely-than-not threshold, and those tax positions requiring recognition are measured as the largest amount of tax benefit that is greater than 50% likely of being realized upon effective settlement with a taxing authority that has full knowledge of all relevant information. Interest and penalties relating to income taxes are included in current income tax expense in our consolidated statement of operations. Our drilling rigs frequently move from one taxing jurisdiction to another based on where they are contracted to perform drilling services. The movement of drilling rigs among taxing jurisdictions may involve a transfer of drilling rig ownership among our subsidiaries through an intercompany rig sale. The pre-tax profit resulting from an intercompany rig sale is eliminated from our consolidated financial statements, and the carrying value of a rig sold in an intercompany transaction remains at historical net depreciated cost prior to the transaction. Our consolidated financial statements do not reflect the asset disposition transaction of the selling subsidiary or the asset acquisition transaction of the acquiring subsidiary. The income tax effects resulting from intercompany rig sales are recognized in earnings in the period in which the sale occurs. In some instances, we may determine that certain temporary differences will not result in a taxable or deductible amount in future years, as it is more-likely-than-not we will commence operations and depart from a given taxing jurisdiction without such temporary differences being recovered or settled. Under these circumstances, no future tax consequences are expected and no deferred taxes are recognized in connection with such operations. We evaluate these determinations on a periodic basis and, in the event our expectations relative to future tax consequences change, the applicable deferred taxes are recognized or derecognized. We do not provide deferred taxes on the undistributed earnings of certain subsidiaries because our policy and intention is to reinvest such earnings indefinitely. Should we make a distribution from these subsidiaries in the form of dividends or otherwise, we may be subject to additional income taxes. The U.S. Tax Cuts and Jobs Act (“U.S. tax reform”) was enacted on December 22, 2017 and introduced significant changes to U.S. income tax law, including a reduction in the statutory income tax rate from 35% to 21% effective January 1, 2018, a one-time transition tax on deemed repatriation of deferred foreign income, a base erosion anti-abuse tax that effectively imposes a minimum tax on certain payments to non-U.S. affiliates, new and revised rules relating to the current taxation of certain income of foreign subsidiaries and revised rules associated with limitations on the deduction of interest. The U.S. Treasury Department issued guidance and continued finalizing rules associated with U.S. tax reform during 2018 and 2019. See " Note 12 - Income Taxes" for additional information. Share-Based Compensation We sponsor share-based compensation plans that provide equity compensation to our key employees, officers and non-employee directors. Our Long-Term Incentive Plan (the “2018 LTIP”) allows our Board of Directors to authorize share grants to be settled in cash or shares. Compensation expense for share awards to be settled in shares is measured at fair value on the date of grant and recognized on a straight-line basis over the requisite service period (usually the vesting period). Compensation expense for share awards to be settled in cash is remeasured each quarter with a cumulative adjustment to compensation cost during the period based on changes in our share price. Any adjustments to the compensation cost recognized in our consolidated statement of operations for awards that are forfeited are recognized in the period in which the forfeitures occur. See " Note 10 - Share Based Compensation" for additional information on our share-based compensation. Pension and Other Post-retirement benefit plans We measure our actuarially determined obligations and related costs for our defined benefit pension and other post-retirement plans, retiree life and medical supplemental plan benefits, by applying assumptions, the most significant of which include long-term rate of return on plan assets, discount rates and mortality rates. For the long-term rate of return, we develop our assumptions regarding the expected rate of return on plan assets based on historical experience and projected long-term investment returns, and we weight the assumptions based on each plan's asset allocation. For the discount rate, we base our assumptions on a yield curve approach. Actual results may differ from the assumptions included in these calculations. If gains or losses exceed 10% of the greater of the plan assets or plan liabilities, we amortize such gains or losses into income over either the period of expected future service of active participants, or over the expected average remaining lifetime of all participants. Fair Value Measurements We measure certain of our assets and liabilities based on a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy assigns the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities ("Level 1") and the lowest priority to unobservable inputs ("Level 3"). Level 2 measurements represent inputs that are observable for similar assets or liabilities, either directly or indirectly, other than quoted prices included within Level 1. See " Note 5 - Fair Value Measurements" for additional information on the fair value measurement of certain of our assets and liabilities. Noncontrolling Interests Third parties hold a noncontrolling ownership interest in certain of our non-U.S. subsidiaries. Noncontrolling interests are classified as equity on our consolidated balance sheet, and net income attributable to noncontrolling interests is presented separately in our consolidated statement of operations. For each of the years in the three-year period ended December 31, 2019 , all income attributable to noncontrolling interest was from continuing operations. Earnings Per Share We compute basic and diluted earnings per share ("EPS") in accordance with the two-class method. Net loss attributable to Valaris used in our computations of basic and diluted EPS is adjusted to exclude net income allocated to non-vested shares granted to our employees and non-employee directors. Weighted-average shares outstanding used in our computation of diluted EPS is calculated using the treasury stock method and includes the effect of all potentially dilutive stock options and excludes non-vested shares. In each of the years in the three-year period ended December 31, 2019 , our potentially dilutive instruments were not included in the computation of diluted EPS as the effect of including these shares in the calculation would have been anti-dilutive. The following table is a reconciliation of loss from continuing operations attributable to Valaris shares used in our basic and diluted EPS computations for each of the years in the three-year period ended December 31, 2019 (in millions): 2019 2018 2017 Loss from continuing operations attributable to Valaris $ (198.0 ) $ (631.6 ) $ (304.7 ) Income from continuing operations allocated to non-vested share awards (.1 ) (.5 ) (.4 ) Loss from continuing operations attributable to Valaris shares $ (198.1 ) $ (632.1 ) $ (305.1 ) Anti-dilutive share awards totaling 300,000 , 1.5 million and 2.0 million for the years ended December 31, 2019, 2018 and 2017 , respectively, were excluded from the computation of diluted EPS. We have the option to settle our 3.00% exchangeable senior notes due 2024 (the "2024 Convertible Notes") in cash, shares or a combination thereof for the aggregate amount due upon conversion. See " Note 7 - Debt" for additional information on this issuance. Our intent is to settle the principal amount of the 2024 Convertible Notes in cash upon conversion. If the conversion value exceeds the principal amount (i.e., our share price exceeds the exchange price on the date of conversion), we expect to deliver shares equal to the remainder of our conversion obligation in excess of the principal amount. During each respective reporting period that our average share price exceeds the exchange price, an assumed number of shares required to settle the conversion obligation in excess of the principal amount will be included in our denominator for the computation of diluted EPS using the treasury stock method. Our average share price did not exceed the exchange price during the years ended December 31, 2019, 2018 and 2017 . New Accounting Pronouncements Recently adopted accounting pronouncements Leases - During 2016, the FASB issued ASU 2016-02, Leases (Topic 842) ("Update 2016-02"), which requires an entity to recognize lease assets and lease liabilities on the balance sheet and to disclose key qualitative and quantitative information about the entity's leasing arrangements. This update is effective for annual and interim periods beginning after December 15, 2018, with early adoption permitted. During our evaluation of Update 2016-02, we concluded that our drilling contracts contain a lease component. In July 2018, the FASB issued Accounting Standard Update 2018-11, Leases (Topic 842), Targeted Improvements , which (1) provided for a new transition method whereby entities could elect to adopt the Update using a prospective with cumulative catch-up approach (the "effective date method") and (2) provided lessors with a practical expedient, by class of underlying asset, to not separate lease and non-lease components and account for the combined component under Topic 606 when the non-lease component is the predominant element of the combined component. The lessor practical expedient is limited to circumstances in which the lease, if accounted for separately, would be classified as an operating lease under Topic 842. We adopted Update 2016-02, effective January 1, 2019, using the effective date method. With respect to our drilling contracts, which contain a lease component, we elected to apply the practical expedient to not separate the lease and non-lease components and account for the combined component under Topic 606. With respect to all of our drilling contracts that existed on the adoption date, we concluded that the criteria to elect the lessor practical expedient had been met. As a result, we will continue to recognize the revenue associated with our drilling contracts under Topic 606. Therefore, we do not expect any change in our revenue recognition patterns or disclosures as a result of our adoption of Topic 842. With respect to leases whereby we are the lessee, we elected several practical expedients afforded under Topic 842. We elected the package of practical expedients permitted under the transition guidance of Topic 842, including the hindsight practical expedient which permits entities to use hindsight in determining the lease term and assessing impairment. We also elected the practical expedient to not separate lease components from non-lease components for all asset classes, with the exception of office space. Furthermore, we also elected the practical expedient that permits entities not to apply the recognition requirements for leases with a term of 12 months or less. Upon adoption of Update 2016-02 on January 1, 2019, we recognized lease liabilities and right-of-use assets of $64.6 million and $53.7 million , respectively. See " Note 14 - Leases" for additional information. Derivatives and Hedging - In August 2017, the Financial Accounting Standards Board (the "FASB") issued ASU 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities ("Update 2017-12"), which makes more hedging strategies eligible for hedge accounting, amends presentation and disclosure requirements and changes how companies assess effectiveness, including the elimination of separate measurement and recognition of ineffectiveness on designated hedging instruments. This update is effective for annual and interim periods beginning after December 15, 2018, with early adoption permitted. We adopted Update 2017-12 effective January 1, 2019. As a result, beginning on the effective date, we no longer separately measure and recognize ineffectiveness on our designated cash flow hedges. Update 2017-02 requires a modified retrospective adoption approach whereby amounts previously recorded to earnings for hedge ineffectiveness on hedging relationships that existed as of the adoption date are recorded as a cumulative effect adjustment to opening retained earnings. As of our adoption date, we had no amounts previously recorded for ineffectiveness for hedging relationships that existed as of our adoption date and therefore no cumulative effect adjustment to retained earnings was recorded. Accounting pronouncements to be adopted Income Taxes - In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes ("Update 2019-12"), which removes certain exceptions for investments, intraperiod allocations and interim tax calculations and adds guidance to reduce complexity in accounting for income taxes. We will be required to adopt the amended guidance in annual and interim periods beginning after December 15, 2020, with early adoption permitted. The various amendments in Update 2019-12 are applied on a retrospective basis, modified retrospective basis and prospective basis, depending on the amendment. We are in the process of evaluating the impact this amendment will have on our consolidated financial statements. Defined Benefit Plans - In August 2018, the FASB issued ASU 2018-14, Compensation – Retirement Benefits – Defined Benefit Plans – General (Subtopic 715-20): Disclosure Framework – Changes to the Disclosure Requirements for Defined Benefit Plans ("Update 2018-14"), which modifies the disclosure requirements for employers that sponsor defined benefit pension or other post-retirement plans. We will be required to adopt the amended guidance in annual and interim reports beginning January 1, 2021, with early adoption permitted. Adoption is required to be applied on a retrospective basis to all periods presented. We will adopt the new standard effective January 1, 2021 and do not expect the adoption of Update 2018-14 to have a material impact on our consolidated financial statements. Credit Losses - In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments ("Update 2016-13"), which requires companies to measure credit losses of financial instruments, including customer accounts receivable, utilizing a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates. Subsequent to the issuance of Update 2016-13, the FASB issued several additional Accounting Standard Updates to clarify implementation guidance, provide narrow-scope improvements and provide additional disclosure guidance. Update 2016-13 is effective for fiscal years beginning after December 15, 2019, with early adoption permitted. We will adopt the new standard effective January 1, 2020 and do not expect the adoption of Update 2016-13 to have a material impact on our consolidated financial statements.

Revenues from Contracts with Cu

Revenues from Contracts with Customers	12 Months Ended
	Dec. 31, 2019
Revenue from Contract with Customer [Abstract]
Revenue from Contract with Customer [Text Block]	REVENUE FROM CONTRACTS WITH CUSTOMERS Our drilling contracts with customers provide a drilling rig and drilling services on a day rate contract basis. Under day rate contracts, we provide an integrated service that includes the provision of a drilling rig and rig crews for which we receive a daily rate that may vary between the full rate and zero rate throughout the duration of the contractual term, depending on the operations of the rig. We also may receive lump-sum fees or similar compensation for the mobilization, demobilization and capital upgrades of our rigs. Our customers bear substantially all of the costs of constructing the well and supporting drilling operations, as well as the economic risk relative to the success of the well. Our integrated drilling service provided under each drilling contract is a single performance obligation satisfied over time and comprised of a series of distinct time increments, or service periods. Total revenue is determined for each individual drilling contract by estimating both fixed and variable consideration expected to be earned over the contract term. Fixed consideration generally relates to activities such as mobilization, demobilization and capital upgrades of our rigs that are not distinct performance obligations within the context of our contracts and is recognized on a straight-line basis over the contract term. Variable consideration generally relates to distinct service periods during the contract term and is recognized in the period when the services are performed. The amount estimated for variable consideration is only recognized as revenue to the extent that it is probable that a significant reversal will not occur during the contract term. We have applied the optional exemption afforded in Update 2014-09, Revenue from Contracts with Customers (Topic 606), and have not disclosed the variable consideration related to our estimated future day rate revenues. The remaining duration of our drilling contracts based on those in place as of December 31, 2019 was between approximately one month and four years. Day Rate Drilling Revenue Our drilling contracts provide for payment on a day rate basis and include a rate schedule with higher rates for periods when the drilling unit is operating and lower rates or zero rates for periods when drilling operations are interrupted or restricted. The day rate invoiced to the customer is determined based on the varying rates applicable to specific activities performed on an hourly basis or other time increment basis. Day rate consideration is allocated to the distinct hourly or other time increment to which it relates within the contract term and is generally recognized consistent with the contractual rate invoiced for the services provided during the respective period. Invoices are typically issued to our customers on a monthly basis and payment terms on customer invoices typically range from 30 to 45 days. Certain of our contracts contain performance incentives whereby we may earn a bonus based on pre-established performance criteria. Such incentives are generally based on our performance over individual monthly time periods or individual wells. Consideration related to performance bonus is generally recognized in the specific time period to which the performance criteria was attributed. We may receive termination fees if certain drilling contracts are terminated by the customer prior to the end of the contractual term. Such compensation is recognized as revenue when our performance obligation is satisfied, the termination fee can be reasonably measured and collection is probable. Mobilization / Demobilization Revenue In connection with certain contracts, we receive lump-sum fees or similar compensation for the mobilization of equipment and personnel prior to the commencement of drilling services or the demobilization of equipment and personnel upon contract completion. Fees received for the mobilization or demobilization of equipment and personnel are included in operating revenues. The costs incurred in connection with the mobilization and demobilization of equipment and personnel are included in contract drilling expense. Mobilization fees received prior to commencement of drilling operations are recorded as a contract liability and amortized on a straight-line basis over the contract term. Demobilization fees expected to be received upon contract completion are estimated at contract inception and recognized on a straight-line basis over the contract term. In some cases, demobilization fees may be contingent upon the occurrence or non-occurrence of a future event. In such cases, this may result in cumulative-effect adjustments to demobilization revenues upon changes in our estimates of future events during the contract term. Capital Upgrade / Contract Preparation Revenue In connection with certain contracts, we receive lump-sum fees or similar compensation for requested capital upgrades to our drilling rigs or for other contract preparation work. Fees received for requested capital upgrades and other contract preparation work are recorded as a contract liability and amortized on a straight-line basis over the contract term to operating revenues. Costs incurred for capital upgrades are capitalized and depreciated over the useful life of the asset. Contract Assets and Liabilities Contract assets represent amounts recognized as revenue but for which the right to invoice the customer is dependent upon our future performance. Once the previously recognized revenue is invoiced, the corresponding contract asset, or a portion thereof, is transferred to accounts receivable. Contract liabilities generally represent fees received for mobilization or capital upgrades. Contract assets and liabilities are presented net on our consolidated balance sheet on a contract-by-contract basis. Current contract assets and liabilities are included in other current assets and accrued liabilities and other, respectively, and noncurrent contract assets and liabilities are included in other assets and other liabilities, respectively, on our consolidated balance sheets. The following table summarizes our contract assets and contract liabilities (in millions): December 31, 2019 December 31, 2018 Current contract assets $ 3.5 $ 4.0 Current contract liabilities (deferred revenue) $ 30.0 $ 56.9 Noncurrent contract liabilities (deferred revenue) $ 9.7 $ 20.5 Changes in contract assets and liabilities during the period are as follows (in millions): Contract Assets Contract Liabilities Balance as of January 1, 2019 $ 4.0 $ 77.4 Contract assets and liabilities acquired in the Rowan Transaction 8.4 5.3 Revenue recognized in advance of right to bill customer 1.3 — Increase due to cash received — 42.9 Decrease due to amortization of deferred revenue that was included in the beginning contract liability balance — (56.3 ) Decrease due to amortization of deferred revenue that was added during the period — (29.6 ) Decrease due to transfer to receivables during the period (10.2 ) — Balance as of December 31, 2019 $ 3.5 $ 39.7 Deferred Contract Costs Costs incurred for upfront rig mobilizations and certain contract preparations are attributable to our future performance obligation under each respective drilling contract. Such costs are deferred and amortized on a straight-line basis over the contract term. Demobilization costs are recognized as incurred upon contract completion. Costs associated with the mobilization of equipment and personnel to more promising market areas without contracts are expensed as incurred. Deferred contract costs were included in other current assets and other assets on our consolidated balance sheets and totaled $19.7 million and $23.5 million as of December 31, 2019 and 2018 , respectively. Amortization of such costs totaled $42.1 million , $34.0 million and $28.1 million for the years ended December 31, 2019 , 2018 and 2017 , respectively. Deferred Certification Costs We must obtain certifications from various regulatory bodies in order to operate our drilling rigs and must maintain such certifications through periodic inspections and surveys. The costs incurred in connection with maintaining such certifications, including inspections, tests, surveys and drydock, as well as remedial structural work and other compliance costs, are deferred and amortized on a straight-line basis over the corresponding certification periods. Deferred regulatory certification and compliance costs were included in other current assets and other assets on our consolidated balance sheets and totaled $10.8 million and $13.6 million as of December 31, 2019 and 2018 , respectively. Amortization of such costs totaled $10.3 million , $12.4 million and $12.1 million for the years ended December 31, 2019 , 2018 and 2017 , respectively. Future Amortization of Contract Liabilities and Deferred Costs Our contract liabilities and deferred costs are amortized on a straight-line basis over the contract term or corresponding certification period to operating revenues and contract drilling expense, respectively. Expected future amortization of our contract liabilities and deferred costs recorded as of December 31, 2019 is set forth in the table below (in millions): 2020 2021 2022 2023 & Thereafter Total Amortization of contract liabilities $ 30.0 $ 7.8 $ 1.9 $ — $ 39.7 Amortization of deferred costs $ 23.2 $ 5.7 $ 1.2 $ 0.4 $ 30.5

Rowan Transaction

Rowan Transaction	12 Months Ended
	Dec. 31, 2019
Business Combinations [Abstract]
Business Combination Disclosure	ROWAN TRANSACTION On October 7, 2018 , we entered into a transaction agreement (the "Transaction Agreement") with Rowan. On April 11, 2019 (the "Transaction Date"), we completed our combination with Rowan pursuant to the Transaction Agreement (the "Rowan Transaction"). Rowan's financial results are included in our consolidating results beginning on the Transaction Date. The Rowan Transaction enhanced the market leadership of the combined company with a fleet of high-specification floaters and jackups and positions us well to meet increasing and evolving customer demand. The increased scale, diversification and financial strength of the combined company provides us advantages to better serve our customers. Consideration As a result of the Rowan Transaction, Rowan shareholders received 2.75 Valaris Class A Ordinary shares for each share of Rowan Class A ordinary share, representing a value of $43.67 per Rowan share based on a closing price of $15.88 per Valaris share on April 10, 2019 , the last trading day before the Transaction Date. Total consideration delivered in the Rowan Transaction consisted of 88.3 million Valaris shares with an aggregate value of $1.4 billion , inclusive of $2.6 million for the estimated fair value of replacement employee equity awards. Upon closing of the Rowan Transaction, we effected a consolidation (being a reverse stock split under English law) where every four existing Class A ordinary shares, each with a nominal value of $0.10 , were consolidated into one Class A ordinary share, each with a nominal value of $0.40 (the "Reverse Stock Split"). All share and per share data included in this report have been retroactively adjusted to reflect the Reverse Stock Split. Assets and Liabilities Acquired Valaris is considered to be the acquirer for accounting purposes. As a result, Rowan's assets and liabilities acquired in the Rowan Transaction were recorded at their estimated fair values as of the Transaction Date under the acquisition method of accounting. When the fair value of the net assets acquired exceeds the consideration transferred in an acquisition, the difference is recorded as a bargain purchase gain in the period in which the transaction occurs. With the exception of certain legal and tax exposures as well as the fair value of materials and supplies, we have substantially completed our fair value assessments of assets acquired and liabilities assumed. While certain adjustments may be recorded during the remainder of the measurement period, we do not expect them to be material. The provisional amounts recorded for assets and liabilities acquired are based on preliminary estimates of their fair values as of the Transaction Date and are as follows (in millions): Amounts Recognized as of Transaction Date Measurement Period Adjustments (1) Estimated Fair Value Assets: Cash and cash equivalents $ 931.9 $ — $ 931.9 Accounts receivable (2) 207.1 (3.6 ) 203.5 Other current assets 101.6 (2.4 ) 99.2 Long-term notes receivable from ARO 454.5 — 454.5 Investment in ARO 138.8 2.5 141.3 Property and equipment 2,989.8 (25.8 ) 2,964.0 Other assets 41.7 1.3 43.0 Liabilities: Accounts payable and accrued liabilities 259.4 13.7 273.1 Current portion of long-term debt 203.2 — 203.2 Long-term debt 1,910.9 — 1,910.9 Other liabilities 376.3 34.1 410.4 Net assets acquired 2,115.6 (75.8 ) 2,039.8 Less: Merger consideration (1,402.8 ) — (1,402.8 ) Bargain purchase gain $ 712.8 $ (75.8 ) $ 637.0 (1) The measurement period adjustments reflect changes in the estimated fair values of certain assets and liabilities, primarily related to long-lived assets, deferred income taxes and uncertain tax positions. The measurement period adjustments were recorded to reflect new information obtained about facts and circumstances existing as of the Transaction Date and did not result from subsequent intervening events. (2) Gross contractual amounts receivable totaled $208.3 million as of the Transaction Date. Bargain Purchase Gain The estimated fair values assigned to assets acquired net of liabilities assumed exceeded the consideration transferred, resulting in a bargain purchase gain primarily driven by the decline in our share price from $33.92 to $15.88 between the last trading day prior to the announcement of the Rowan Transaction and the Transaction Date. Transaction-Related Costs Merger-related costs were expensed as incurred and consisted of various advisory, legal, accounting, valuation and other professional or consulting fees totaling $18.0 million for the year ended December 31, 2019 . These costs are included in general and administrative expense in our consolidated statements of operations. Materials and Supplies We recorded materials and supplies at an estimated fair value of $83.0 million . Materials and supplies consist of consumable parts and supplies maintained on drilling rigs and in shore-based warehouse locations for use in operations and are generally comprised of items of low per unit cost and high reorder frequency. We estimated the fair value of Rowan's materials and supplies primarily using a market approach. Equity Method Investment in ARO The equity method investment in ARO was recorded at its estimated fair value as of the Transaction Date. See Note 4 for additional information on ARO. We estimated the fair value of the equity investment primarily by applying an income approach, using projected discounted cash flows of the underlying assets, a risk-adjusted discount rate and an estimated effective income tax rate. Property and Equipment Property and equipment acquired in connection with the Rowan Transaction consisted primarily of drilling rigs and related equipment, including four drillships and 19 jackup rigs (exclusive of two jackups marked for retirement). We recorded property and equipment acquired at its estimated fair value of $3.0 billion . We estimated the fair value of the rigs and equipment by applying an income approach, using projected discounted cash flows, a risk-adjusted discount rate and an estimated effective income tax rate. The estimated remaining useful lives for Rowan's drilling rigs, which ranged from 16 to 35 years based on original estimated useful lives of 30 to 35 years. Intangible Assets and Liabilities We recorded intangible assets and liabilities of $16.2 million and $2.1 million , respectively, representing the estimated fair value of Rowan's firm contracts in place at the Transaction Date with favorable or unfavorable contract terms compared to then-market day rates for comparable drilling rigs. The various factors considered in the determination of these fair values were (1) the contracted day rate for each contract, (2) the remaining term of each contract, (3) the rig class and (4) the market conditions for each respective rig class at the Transaction Date. The intangible assets and liabilities were calculated based on the present value of the difference in cash flows over the remaining contract term as compared to a hypothetical contract with the same remaining term at an estimated then-current market day rate using a risk-adjusted discount rate and an estimated effective income tax rate. Amortization of the intangible assets and liabilities resulted in a net reduction in operating revenues of $3.6 million for the year ended December 31, 2019 . The remaining balance of intangible assets and liabilities of $11.9 million and $1.4 million , respectively, was included in other assets and other liabilities, respectively, on our consolidated balance sheet of December 31, 2019 . These balances will be amortized to operating revenues over the respective remaining contract terms on a straight-line basis. As of December 31, 2019 , the remaining terms of the underlying contracts is approximately 2 years. Amortization of these intangibles is expected to result in a reduction to revenue of $5.1 million and $5.4 million in 2020 and 2021, respectively. Pension and Other Post-retirement benefit plans We remeasured the fair value of plan assets and benefit obligations for the pension and other-post retirement benefit plans assumed as of April 11, 2019. We used a measurement date of April 11, 2019 for determining net periodic benefit costs. Long-term Debt We recorded Rowan's long-term debt at its estimated fair value as of the Transaction Date, which was based on quoted market prices as of April 10, 2019 . Deferred Taxes The Rowan Transaction was executed through the acquisition of Rowan's outstanding ordinary shares and, therefore, the historical tax bases of the acquired assets and liabilities, net operating losses and other tax attributes of Rowan, were acquired as of the Transaction Date. However, adjustments were recorded to recognize deferred tax assets and liabilities for the tax effects of differences between acquisition date fair values and tax bases of assets acquired and liabilities assumed. Additionally, the interaction of our and Rowan's tax attributes that impacted the deferred taxes of the combined entity were also recognized as part of acquisition accounting. As of the Transaction Date, a decrease of $99.0 million to Rowan's historical net deferred tax assets was recognized. Deferred tax assets and liabilities recognized in connection with the Rowan Transaction were measured at rates enacted as of the Transaction Date. Tax rate changes, or any deferred tax adjustments for new tax legislation, following the Transaction Date will be reflected in our operating results in the period in which the change in tax laws or rate is enacted. Uncertain Tax Positions Uncertain tax positions assumed in a business combination are measured at the largest amount of the tax benefit that is greater than 50% likely of being realized upon effective settlement with a taxing authority that has full knowledge of all relevant information. As of the Transaction Date, Rowan had previously recognized net liabilities for uncertain tax positions totaling $50.4 million . During 2019 , we received income tax assessments from Luxembourg tax authorities related to certain filing positions taken by Rowan in prior years for several of Rowan’s Luxembourg subsidiaries totaling approximately €142.0 million (approximately $159.0 million converted using the current period-end exchange rate). We are contesting these assessments and have filed applications for appeal. As of the Transaction Date, we recognized liabilities under acquisition accounting of €47.0 million (approximately $52.0 million converted using the current period-end exchange rate) in connection with the Luxembourg assessments, which reflected the amount of the Rowan filing positions that we concluded, on a preliminary basis, we would not more-likely-than-not sustain. As a result of our continued review and analysis of facts and circumstances that existed at the Transaction Date, we recognized additional liabilities of €46.0 million (approximately $52.6 million converted using the current period-end exchange rate) as measurement period adjustments. As a result, the amount recognized on our consolidated balance sheet related to the Luxembourg income tax assessments totaled €93.0 million (approximately $104.6 million converted using the current period-end exchange rates) as of December 31, 2019 . Our ongoing evaluation of the relevant facts and circumstances surrounding these positions may result in further revisions to this estimate, which could be material. We cannot predict or provide assurance as to the ultimate outcome of the Luxembourg tax assessments. Revenues and Earnings of Rowan Our consolidated statement of operations for the year ending December 31, 2019 included revenues of $448.0 million and net losses of $122.7 million . Unaudited Pro Forma Impact of the Rowan Transaction The following unaudited supplemental pro forma results present consolidated information as if the Rowan Transaction was completed on January 1, 2018. The pro forma results include, among others, (1) the amortization associated with acquired intangible assets and liabilities, (2) a reduction in depreciation expense for adjustments to property and equipment, (3) the amortization of premiums and discounts recorded on Rowan's debt, (4) removal of the historical amortization of unrealized gains and losses related to Rowan's pension plans and (5) the amortization of basis differences in assets and liabilities of ARO. The pro forma results do not include any potential synergies or non-recurring charges that may result directly from the Rowan Transaction. (unaudited) (in millions, except per share amounts) Year Ended 2019 (1) 2018 (2) Revenues $ 2,240.5 $ 2,530.4 Net loss $ (994.3 ) $ (796.5 ) Earnings per share - basic and diluted $ (3.80 ) $ (4.05 ) (1) Pro forma net loss per share was adjusted to exclude an aggregate $108.1 million of transaction-related and integration costs incurred by Ensco and Rowan during 2019 and the $637.0 million bargain purchase gain. (2) Pro forma net loss per share was adjusted to exclude an aggregate $13.8 million

Equity Method Investment in ARO

Equity Method Investment in ARO	12 Months Ended
	Dec. 31, 2019
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments in ARO	Equity Method Investment in ARO Background During 2016, Rowan and Saudi Aramco entered into an agreement to create a 50/50 joint venture (the "Shareholders' Agreement") to own, manage and operate offshore drilling rigs in Saudi Arabia. The new entity, ARO, was formed in May 2017 with each of Rowan and Saudi Aramco contributing $25 million to be used for working capital needs. In October 2017, Rowan sold rigs Bob Keller, J.P. Bussell and Gilbert Rowe to ARO and Saudi Aramco sold SAR 201 and related assets to ARO in each case for cash. Upon completion of the rig sales, ARO was deemed to have commenced operations. Saudi Aramco subsequently sold another rig, SAR 202, to ARO in December 2017 for cash and in October 2018, Rowan sold two additional jackup rigs, the Scooter Yeargain and the Hank Boswell, to ARO for cash. As a result of these rig sales, ARO owned seven jackup rigs as of the Transaction Date. During 2017 and 2018, Rowan contributed cash to ARO in exchange for 10-year shareholder notes receivable at a stated interest rate of LIBOR plus two percent. As of December 31, 2019 , the carrying amount of the long-term notes receivable from ARO was $452.9 million. The Shareholders’ Agreement prohibits the sale or transfer of the shareholder note to a third party, except in certain limited circumstances. Rigs purchased by ARO will receive contracts from Saudi Aramco for an aggregate 15 years , renewed and re-priced every three years , provided that the rigs meet the technical and operational requirements of Saudi Aramco. Each of the seven rigs owned by ARO is currently operating under its initial three-year contract. Additionally, prior to the Rowan Transaction, Rowan entered into agreements with ARO to lease nine rigs to ARO (the "Lease Agreements"). The rigs are leased to ARO through bareboat charter arrangements whereby substantially all operating costs are incurred by ARO. As of December 31, 2019 , all nine of the rigs were operating under three-year drilling contracts with Saudi Aramco. Valaris and Saudi Aramco have agreed to take all steps necessary to ensure that ARO purchases 20 newbuild jackup rigs ratably over an approximate 10 -year period. In January 2020, ARO ordered the first two newbuild jackups, each with a price of $176 million, for delivery scheduled in 2022. The partners intend for the newbuild jackup rigs to be financed out of available cash from ARO's operations and/or funds available from third-party debt financing. In the event ARO has insufficient cash from operations or is unable to obtain third-party financing, each partner may periodically be required to make additional capital contributions to ARO, up to a maximum aggregate contribution of $1.25 billion from each partner to fund the newbuild program. Each partner's commitment shall be reduced by the actual cost of each newbuild rig, on a proportionate basis. The partners agreed that Saudi Aramco, as a customer, will provide drilling contracts to ARO in connection with the acquisition of the newbuild rigs. The initial contracts provided by Saudi Aramco for each of the newbuild rigs will be for an eight-year term. The day rate for the initial contracts for each newbuild rig will be determined using a pricing mechanism that targets a six-year payback period for construction costs on an EBITDA basis. The initial eight-year contracts will be followed by a minimum of another eight years of term, re-priced in three-year intervals based on a market pricing mechanism. Upon establishment of ARO, Rowan also entered into (1) an agreement to provide certain back-office services for a period of time until ARO develops its own infrastructure (the "Transition Services Agreement"), and (2) an agreement to provide certain Rowan employees through secondment arrangements to assist with various onshore and offshore services for the benefit of ARO (the "Secondment Agreement"). These agreements remain in place subsequent to the Rowan Transaction. Pursuant to these agreements, we or our seconded employees provide various services to ARO, and in return, ARO provides remuneration for those services. From time to time, we may also sell equipment or supplies to ARO. Summarized Financial Information The operating revenues of ARO presented below reflect revenues earned under drilling contracts with Saudi Aramco for the seven ARO-owned jackup rigs and the rigs leased from us that operated from the Transaction Date through December 31, 2019 . The contract drilling expenses, depreciation and general and administrative expenses presented below are also for the period from the Transaction Date through December 31, 2019 . Contract drilling expense is inclusive of the bareboat charter fees for the rigs leased from us. Cost incurred under the Secondment Agreement are included in contract drilling expense and general and administrative, depending on the function to which the seconded employee's service relates. Substantially all costs incurred under the Transition Services Agreement are included in general and administrative. See additional discussion below regarding these related-party transactions. Summarized financial information for ARO is as follows (in millions): April 11, 2019 - December 31, 2019 Revenues $ 410.5 Operating expenses Contract drilling (exclusive of depreciation) 280.2 Depreciation 40.3 General and administrative 27.1 Operating income 62.9 Other expense, net 28.6 Provision for income taxes 9.7 Net income $ 24.6 December 31, 2019 Current assets $ 407.2 Non-current assets 874.8 Total assets $ 1,282.0 Current liabilities $ 183.2 Non-current liabilities 1,015.5 Total liabilities $ 1,198.7 Equity in Earnings of ARO We account for our interest in ARO using the equity method of accounting and only recognize our portion of ARO's net income, adjusted for basis differences as discussed below, which is included in equity in earnings of ARO in our consolidated statements of operations. ARO is a variable interest entity; however, we are not the primary beneficiary and therefore do not consolidate ARO. Judgments regarding our level of influence over ARO included considering key factors such as: each partner's ownership interest, representation on the board of managers of ARO and ability to direct activities that most significantly impact ARO's economic performance, including the ability to influence policy-making decisions. As a result of the Rowan Transaction, we recorded our equity method investment in ARO at its estimated fair value on the Transaction Date. Additionally, we computed the difference between the fair value of ARO's net assets and the carrying value of those net assets in ARO's US GAAP financial statements ("basis differences"). The basis differences primarily relate to ARO's long-lived assets and the recognition of intangible assets associated with certain of ARO's drilling contracts that were determined to have favorable terms as of the Transaction Date. The basis differences are amortized over the remaining life of the assets or liabilities to which they relate and are recognized as an adjustment to the equity in earnings of ARO in our consolidated statements of operations. The amortization of those basis differences are combined with our 50% interest in ARO's net income. A reconciliation of those components is presented below (in millions): April 11, 2019 - December 31, 2019 50% interest in ARO net income $ 12.3 Amortization of basis differences (24.9 ) Equity in earnings of ARO $ (12.6 ) Related-Party Transactions Revenues recognized by us related to the Lease Agreements, Transition Services Agreement and Secondment Agreement are as follows (in millions): Year Ended December 31, 2019 Lease revenue $ 58.2 Secondment revenue 49.9 Transition Services revenue 17.3 Total revenue from ARO (1) $ 125.4 (1) All of the revenues presented above are included in our Other segment in our segment disclosures. See Note 15 for additional information. Amounts receivable from ARO related to the above items totaled $21.8 million as of December 31, 2019 and are included in accounts receivable, net, on our consolidated balance sheet. Accounts payable to ARO totaled $0.7 million as of December 31, 2019 . We also have an agreement between us and ARO, pursuant to which ARO will reimburse us for certain capital expenditures related to the shipyard upgrade projects for VALARIS JU-147 and VALARIS JU-148. As of December 31, 2019 , $14.2 million related to reimbursement of these expenditures was included in accounts receivable, net, on our consolidated balance sheet. During 2017 and 2018, Rowan contributed cash to ARO in exchange for 10-year shareholder notes receivable at a stated interest rate of LIBOR plus two percent . Interest is recognized as interest income in our consolidated statement of operations and totaled $16.8 million for the period from the Transaction Date through December 31, 2019 , respectively. As of December 31, 2019 , we had no interest receivable from ARO. The following table summarizes the maturity schedule of our notes receivable from ARO as of December 31, 2019 (in millions): Maturity Date Principal Amount October 2027 $ 275.2 October 2028 177.7 Total $ 452.9 Maximum Exposure to Loss The following summarizes the total assets and liabilities as reflected in our consolidated balance sheet as well as our maximum exposure to loss related to ARO (in millions). Our maximum exposure to loss is limited to (1) our equity investment in ARO; (2) the outstanding balance on our shareholder notes receivable; and (3) other receivables for services provided to ARO, partially offset by payables for services received. December 31, 2019 Total assets $ 623.5 Less: total liabilities .7 Maximum exposure to loss $ 622.8

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurements	FAIR VALUE MEASUREMENTS The following fair value hierarchy table categorizes information regarding our financial assets and liabilities measured at fair value on a recurring basis as of December 31, 2019 and 2018 (in millions): Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total As of December 31, 2019 Supplemental executive retirement plan assets $ 26.0 $ — $ — $ 26.0 Derivatives, net — 5.4 — 5.4 Total financial assets $ 26.0 $ 5.4 $ — $ 31.4 As of December 31, 2018 Supplemental executive retirement plan assets $ 27.2 $ — $ — $ 27.2 Total financial assets 27.2 — — 27.2 Derivatives, net — (10.7 ) — (10.7 ) Total financial liabilities $ — $ (10.7 ) $ — $ (10.7 ) Supplemental Executive Retirement Plans Our Valaris supplemental executive retirement plans (the "SERPs") are non-qualified plans that provide eligible employees an opportunity to defer a portion of their compensation for use after retirement. The SERPs were frozen to the entry of new participants in November 2019 and to future compensation deferrals as of January 1, 2020. Assets held in the SERP were marketable securities measured at fair value on a recurring basis using Level 1 inputs and were included in other assets, net, on our consolidated balance sheets as of December 31, 2019 and 2018 . The fair value measurements of assets held in the SERP were based on quoted market prices. Net unrealized gains of $5.0 million , losses of $700,000 and gains of $4.5 million from marketable securities held in our SERP were included in other, net, in our consolidated statements of operations for the years ended December 31, 2019, 2018 and 2017 , respectively. Derivatives Our derivatives were measured at fair value on a recurring basis using Level 2 inputs as of December 31, 2019 and 2018 . See "Note 8 - Derivative Instruments" for additional information on our derivatives, including a description of our foreign currency hedging activities and related methodologies used to manage foreign currency exchange rate risk. The fair value measurements of our derivatives were based on market prices that are generally observable for similar assets or liabilities at commonly quoted intervals. Other Financial Instruments The carrying values and estimated fair values of our debt instruments as of December 31, 2019 and 2018 were as follows (in millions): December 31, 2019 December 31, 2018 Carrying Value Estimated Fair Value Carrying Value Estimated Fair Value 6.875% Senior notes due 2020 $ 124.8 $ 117.3 $ 127.5 $ 121.6 4.70% Senior notes due 2021 113.2 95.5 112.7 101.8 4.875% Senior notes due 2022 (2) 599.2 460.5 — — 3.00% Exchangeable senior notes due 2024 (1) 699.0 607.4 666.8 575.5 4.50% Senior notes due 2024 302.0 167.2 619.8 405.2 4.75% Senior notes due 2024 (2) 276.5 201.4 — — 8.00% Senior notes due 2024 295.7 181.7 337.0 273.7 5.20% Senior notes due 2025 331.7 186.7 664.4 443.9 7.375% Senior notes due 2025 (2) 329.2 218.6 — — 7.75% Senior notes due 2026 987.1 575.1 985.0 725.5 7.20% Debentures due 2027 111.7 70.0 149.3 109.1 7.875% Senior notes due 2040 373.3 153.5 375.0 223.2 5.40% Senior notes due 2042 (2) 262.8 194.4 — — 5.75% Senior notes due 2044 973.3 450.0 972.9 566.3 5.85% Senior notes due 2044 (2) 268.8 194.8 — — Total debt $ 6,048.3 $ 3,874.1 $ 5,010.4 $ 3,545.8 Less: current maturities 124.8 — — — Total long-term debt $ 5,923.5 $ 3,874.1 $ 5,010.4 $ 3,545.8 (1) Our 2024 Convertible Notes were issued with a conversion feature. The 2024 Convertible Notes were separated into their liability and equity components on our consolidated balance sheet. The equity component was initially recorded to additional paid-in capital and as a debt discount that will be amortized to interest expense over the life of the instrument. Excluding the unamortized discount, the carrying value of the 2024 Convertible Notes was $838.3 million and $836.3 million as of December 31, 2019 and 2018 , respectively. See "Note 7 - Debt" for additional information on this issuance. (2) These senior notes were assumed by Valaris as a result of the Rowan Transaction. The estimated fair values of our senior notes and debentures were determined using quoted market prices, which are level 1 inputs. The estimated fair values of our cash and cash equivalents, short-term investments, accounts receivable, notes receivable, trade payables and other liabilities approximated their carrying values as of December 31, 2019 and 2018 . Our short-term investments consisted of time deposits with initial maturities in excess of three months but less than one year as of December 31, 2018.

Property And Equipment

Property And Equipment	12 Months Ended
	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Property And Equipment	PROPERTY AND EQUIPMENT Property and equipment as of December 31, 2019 and 2018 consisted of the following (in millions): 2019 2018 Drilling rigs and equipment $ 17,714.0 $ 14,542.5 Work-in-progress 473.6 779.2 Other 206.2 195.3 $ 18,393.8 $ 15,517.0 Drilling rigs and equipment as of December 31, 2019 increased by $3.2 billion , or 22% , as compared to prior period, primarily due to $3.0 billion of assets acquired from the Rowan Transaction, and $385.0 million due to VALARIS JU-123 which was placed into service in the current period. Work-in-progress as of December 31, 2019 primarily consisted of $417.4 million related to the construction of ultra-deepwater drillships VALARIS DS-13 and VALARIS DS-14. Work-in-progress as of December 31, 2018 primarily consisted of $416.8 million related to the construction of ultra-deepwater drillships VALARIS DS-13 and VALARIS DS-14 and $352.4 million related to the construction of VALARIS JU-123, an ultra-premium harsh environment jackup rig. VALARIS JU-123 was placed into service and reclassified from work-in-progress to drilling rigs and equipment during the year ended December 31, 2019 . Impairment of Long-Lived Assets On a quarterly basis, we evaluate the carrying value of our property and equipment to identify events or changes in circumstances ("triggering events") that indicate the carrying value may not be recoverable. Together with the Rowan Transaction, and as a result of the evaluation of the strategy of the combined fleet, we determined that a triggering event occurred resulting in the performance of a fleet-wide recoverability test. We determined that estimated undiscounted cash flows were sufficient to cover the rigs carrying values and concluded that no impairments were necessary. During 2019 , we recorded a pre-tax, non-cash loss on impairment of $98.4 million on two older, non-core assets in our fleet upon classification as held-for-sale. We determined that the fair value less cost to sell was lower than each rig's carrying value and concluded that the rigs were impaired. During 2018 , we recorded a pre-tax, non-cash loss on impairment of $40.3 million related to one older non-core jackup rig. We concluded that a triggering event occurred due to the expiration of a legacy higher day rate contract resulting in the performance of a recoverability test. We determined that the estimated undiscounted cash flows over the remaining useful life of the rig were not sufficient to recover the rig’s carrying value and concluded the rig was impaired as of December 31, 2018 . During 2017 , we recognized a pre-tax, non-cash loss on impairment of $182.9 million related to older, less capable, non-core assets in our fleet. We determined that the remaining useful life of certain non-core rigs would not extend substantially beyond their current contracts, resulting in triggering events and the performance of recoverability tests. Our estimates of undiscounted cash flows over the revised estimated remaining useful lives were not sufficient to recover each asset’s carrying value. Accordingly, we concluded that two semisubmersibles and one jackup were impaired as of December 31, 2017 . For rigs classified as held-for-sale, we recorded an impairment for the difference between their carrying value and the fair value less costs to sell. We estimated fair value using significant other observable inputs including indicative scrap values based on historical sale prices. For rigs whose carrying values were determined not to be recoverable, we recorded an impairment for the difference between their fair values and carrying values. We estimated the fair values of these rigs by applying an income approach, using projected discounted cash flows. These valuations were based on unobservable inputs that require significant judgments for which there is limited information, including assumptions regarding future day rates, utilization, operating costs and capital requirements. Forecasted day rates and utilization took into account market conditions and our anticipated business outlook. If the global economy, our overall business outlook and/or our expectations regarding the marketability of one or more of our drilling rigs deteriorate further, we may conclude that a triggering event has occurred and perform a recoverability test that could lead to a material impairment charge in future periods.

Debt

Debt	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
Debt	DEBT The carrying value of our long-term debt as of December 31, 2019 and 2018 consisted of the following (in millions): 2019 2018 6.875% Senior notes due 2020 $ 124.8 $ 127.5 4.70% Senior notes due 2021 113.2 112.7 4.875% Senior notes due 2022 (3) 599.2 — 3.00% Exchangeable senior notes due 2024 (2) 699.0 666.8 4.50% Senior notes due 2024 (1) 302.0 619.8 4.75% Senior notes due 2024 (3) 276.5 — 8.00% Senior notes due 2024 (1) 295.7 337.0 5.20% Senior notes due 2025 (1) 331.7 664.4 7.375% Senior notes due 2025 (3) 329.2 — 7.75% Senior notes due 2026 987.1 985.0 7.20% Debentures due 2027 (1) 111.7 149.3 7.875% Senior notes due 2040 373.3 375.0 5.40% Senior notes due 2042 (3) 262.8 — 5.75% Senior notes due 2044 973.3 972.9 5.85% Senior notes due 2044 (3) 268.8 — Total debt $ 6,048.3 $ 5,010.4 Less: current maturities 124.8 — Total long-term debt $ 5,923.5 $ 5,010.4 (1) The decline in the carrying value of our 4.50% and 8.00% senior notes due 2024, 5.20% senior notes due 2025 and 7.20% debentures due 2027 resulted from repurchases made pursuant to the tender offer discussed below. (2) Our 2024 Convertible Notes were issued with a conversion feature. The 2024 Convertible Notes were separated into their liability and equity components on our consolidated balance sheet. The equity component was initially recorded to additional paid-in capital and as a debt discount that will be amortized to interest expense over the life of the instrument. Excluding the unamortized discount, the carrying value of the 2024 Convertible Notes was $838.3 million and $836.3 million as of December 31, 2019 and 2018 , respectively. (3) These senior notes were acquired in the Rowan Transaction. 2024 Convertible Notes In December 2016, Ensco Jersey Finance Limited, a wholly-owned subsidiary of Valaris plc, issued $849.5 million aggregate principal amount of unsecured 2024 Convertible Notes in a private offering. The 2024 Convertible Notes are fully and unconditionally guaranteed, on a senior, unsecured basis, by Valaris plc and are exchangeable into cash, our Class A ordinary shares or a combination thereof, at our election. Interest on the 2024 Convertible Notes is payable semiannually on January 31 and July 31 of each year. The 2024 Convertible Notes will mature on January 31, 2024, unless exchanged, redeemed or repurchased in accordance with their terms prior to such date. Holders may exchange their 2024 Convertible Notes at their option any time prior to July 31, 2023 only under certain circumstances set forth in the indenture governing the 2024 Convertible Notes. On or after July 31, 2023, holders may exchange their 2024 Convertible Notes at any time. The exchange rate is 17.8336 shares per $1,000 principal amount of notes, representing an exchange price of $56.08 per share, and is subject to adjustment upon certain events. The 2024 Convertible Notes may not be redeemed by us except in the event of certain tax law changes. Upon conversion of the 2024 Convertible Notes, holders will receive cash, our Class A ordinary shares or a combination thereof, at our election. Our intent is to settle the principal amount of the 2024 Convertible Notes in cash upon conversion. If the conversion value exceeds the principal amount (i.e., our share price exceeds the exchange price on the date of conversion), we expect to deliver shares equal to our conversion obligation in excess of the principal amount. During each respective reporting period that our average share price exceeds the exchange price, an assumed number of shares required to settle the conversion obligation in excess of the principal amount will be included in the denominator for our computation of diluted EPS using the treasury stock method. See " Note 1 - Description of the Business and Summary of Significant Accounting Policies" for additional information regarding the impact to our EPS. The 2024 Convertible Notes were separated into their liability and equity components and included in long-term debt and additional paid-in capital on our consolidated balance sheet, respectively. The carrying amount of the liability component was calculated by measuring the estimated fair value of a similar liability that does not include an associated conversion feature. The carrying amount of the equity component representing the conversion feature was determined by deducting the fair value of the liability component from the principal amount of the 2024 Convertible Notes. The difference between the carrying amount of the liability and the principal amount is amortized to interest expense over the term of the 2024 Convertible Notes, together with the coupon interest, resulting in an effective interest rate of approximately 8% per annum. The equity component is not remeasured if we continue to meet certain conditions for equity classification. The costs related to the issuance of the 2024 Convertible Notes were allocated to the liability and equity components based on their relative fair values. Issuance costs attributable to the liability component are amortized to interest expense over the term of the notes and the issuance costs attributable to the equity component were recorded to additional paid-in capital on our consolidated balance sheet. As of December 31, 2019 and 2018 , the 2024 Convertible Notes consist of the following (in millions): Liability component: 2019 2018 Principal $ 849.5 $ 849.5 Less: Unamortized debt discount and issuance costs (150.5 ) (182.7 ) Net carrying amount 699.0 666.8 Equity component, net $ 220.0 $ 220.0 During the year ended December 31, 2019 , 2018 and 2017 , we recognized $25.5 million associated with coupon interest. Amortization of debt discount and issuance costs were $32.5 million , $31.0 million and $31.4 million for the years ended December 31, 2019 , 2018 and 2017 , respectively. The indenture governing the 2024 Convertible Notes contains customary events of default, including failure to pay principal or interest on such notes when due, among others. The indenture also contains certain restrictions, including, among others, restrictions on our ability and the ability of our subsidiaries to create or incur secured indebtedness, enter into certain sale/leaseback transactions and enter into certain merger or consolidation transactions. Senior Notes As a result of the Rowan Transaction, we acquired the following debt issued by Rowan Companies, Inc. ("RCI") and guaranteed by Rowan: (1) $201.4 million in aggregate principal amount of 7.875% unsecured senior notes, which was repaid at maturity in August 2019, (2) $620.8 million in aggregate principal amount of 4.875% unsecured senior notes due 2022 (the "Rowan 2022 Notes"), (3) $398.1 million in aggregate principal amount of 4.75% unsecured senior notes due 2024 (the "Rowan 2024 Notes"), (4) $500.0 million in aggregate principal amount of 7.375% unsecured senior notes due 2025 (the "Rowan 2025 Notes"), (5) $400.0 million in aggregate principal amount of 5.4% unsecured senior notes due 2042 (the "Rowan 2042 Notes") and (6) $400.0 million in aggregate principal amount of 5.85% unsecured senior notes due 2044 (the "Rowan 2044 Notes" and collectively, the "Rowan Notes"). Upon closing of the Rowan Transaction, we terminated Rowan's outstanding credit facilities. On February 3, 2020, Rowan and RCI transferred substantially all their assets on a consolidated basis to Valaris plc, Valaris plc became the obligor on the notes and Rowan and RCI were relieved of their obligations under the notes and the related indenture. On January 26, 2018, we issued $1.0 billion aggregate principal amount of unsecured 7.75% senior notes due 2026 (the "2026 Notes") at par, net of $16.5 million of debt issuance costs. Interest on the 2026 Notes is payable semiannually on February 1 and August 1 of each year. During 2017, we exchanged $332.0 million aggregate principal amount of unsecured 8.00% senior notes due 2024 (the “8 % 2024 Notes”) for certain amounts of our outstanding senior notes due 2019, 2020 and 2021. Interest on the 8% 2024 Notes is payable semiannually on January 31 and July 31 of each year. During 2015, we issued $700.0 million aggregate principal amount of unsecured 5.20% senior notes due 2025 (the “2025 Notes”) at a discount of $2.6 million and $400.0 million aggregate principal amount of unsecured 5.75% senior notes due 2044 (the “New 2044 Notes”) at a discount of $18.7 million in a public offering. Interest on the 2025 Notes is payable semiannually on March 15 and September 15 of each year. Interest on the New 2044 Notes is payable semiannually on April 1 and October 1 of each year. During 2014, we issued $625.0 million aggregate principal amount of unsecured 4.50% senior notes due 2024 (the "2024 Notes") at a discount of $0.9 million and $625.0 million aggregate principal amount of unsecured 5.75% senior notes due 2044 (the "Existing 2044 Notes" and together with the New 2044 Notes, the "2044 Notes") at a discount of $2.8 million . Interest on the 2024 Notes and the Existing 2044 Notes is payable semiannually on April 1 and October 1 of each year. The Existing 2044 Notes and the New 2044 Notes are treated as a single series of debt securities under the indenture governing the notes. During 2011, we issued $1.5 billion aggregate principal amount of unsecured 4.70% senior notes due 2021 (the “2021 Notes”) at a discount of $29.6 million in a public offering. Interest on the 2021 Notes is payable semiannually on March 15 and September 15 of each year. Upon consummation of the Pride International LLC ("Pride") acquisition during 2011, we assumed outstanding debt comprised of $900.0 million aggregate principal amount of unsecured 6.875% senior notes due 2020 , $500.0 million aggregate principal amount of unsecured 8.5% senior notes due 2019 and $300.0 million aggregate principal amount of unsecured 7.875% senior notes due 2040 (collectively, the "Acquired Notes" and together with the Rowan Notes, 2021 Notes, 8% 2024 Notes, 2024 Notes, 2025 Notes, 2026 Notes and 2044 Notes, the "Senior Notes"). Valaris plc has fully and unconditionally guaranteed the performance of all Pride obligations with respect to the Acquired Notes. See " Note 17 - Guarantee of Registered Securities " for additional information on the guarantee of the Acquired Notes. We may redeem the Senior Notes in whole at any time, or in part from time to time, prior to maturity. If we elect to redeem the Rowan 2022 Notes, Rowan 2024 Notes, 8% 2024 Notes, 2024 Notes, 2025 Notes, Rowan 2025 Notes and 2026 Notes before the date that is three months prior to the maturity date or the Rowan 2042 Notes, Rowan 2044 Notes and 2044 Notes before the date that is six months prior to the maturity date, we will pay an amount equal to 100% of the principal amount of the notes redeemed plus accrued and unpaid interest and a "make-whole" premium. If we elect to redeem these notes on or after the aforementioned dates, we will pay an amount equal to 100% of the principal amount of the notes redeemed plus accrued and unpaid interest but we are not required to pay a "make-whole" premium. We may redeem each series of the 2021 Notes and the Acquired Notes, in whole or in part, at any time at a price equal to 100% of their principal amount, plus accrued and unpaid interest and a "make-whole" premium. The indentures governing the Senior Notes contain customary events of default, including failure to pay principal or interest on such notes when due, among others. The indentures governing the Senior Notes also contain certain restrictions, including, among others, restrictions on our ability and the ability of our subsidiaries to create or incur secured indebtedness, enter into certain sale/leaseback transactions and enter into certain merger or consolidation transactions. Debentures Due 2027 During 1997, Ensco International Incorporated issued $150.0 million of unsecured 7.20% Debentures due 2027 (the "Debentures"). Interest on the Debentures is payable semiannually on May 15 and November 15 of each year. We may redeem the Debentures, in whole or in part, at any time prior to maturity, at a price equal to 100% of their principal amount, plus accrued and unpaid interest and a "make-whole" premium. During 2009, Ensco plc entered into a supplemental indenture to unconditionally guarantee the principal and interest payments on the Debentures. See " Note 17 - Guarantee of Registered Securities " for additional information on the guarantee of the Debentures. The Debentures and the indenture pursuant to which the Debentures were issued also contain customary events of default, including failure to pay principal or interest on the Debentures when due, among others. The indenture also contains certain restrictions, including, among others, restrictions on our ability and the ability of our subsidiaries to create or incur secured indebtedness, enter into certain sale/leaseback transactions and enter into certain merger or consolidation transactions. Tender Offers and Open Market Repurchases On June 25, 2019, we commenced cash tender offers for certain series of senior notes issued by us, Ensco International Incorporated and RCI, our wholly-owned subsidiaries. The tender offers expired on July 23, 2019, and we repurchased $951.8 million of our outstanding senior notes for an aggregate purchase price of $724.1 million . As a result of the transaction, we recognized a pre-tax gain from debt extinguishment of $194.1 million , net of discounts, premiums and debt issuance costs in other, net, in the consolidated statement of operations. Concurrent with the issuance of the 2026 Notes in January 2018, we launched cash tender offers for up to $985.0 million aggregate principal amount of certain series of senior notes issued by us and Pride, our wholly-owned subsidiary, and as a result we repurchased $595.4 million of our senior notes. Subsequently, we issued a redemption notice for the remaining principal amount of the $55.0 million principal amount of the 8.50% senior notes due 2019 and repurchased $71.4 million principal amount of our senior notes due 2020. As a result of these transactions, we recognized a pre-tax loss from debt extinguishment of $19.0 million , net of discounts, premiums, debt issuance costs and commissions in other, net, in the consolidated statement of operations. During 2017, we repurchased $194.1 million of our outstanding senior notes on the open market for an aggregate purchase price of $204.5 million with cash on hand and recognized an insignificant pre-tax gain, net of discounts, premiums and debt issuance costs. Our tender offers and open market repurchases during the three-year period ended December 31, 2019 were as follows (in millions): Aggregate Principal Amount Repurchased Aggregate Repurchase Price (1) Year Ended December 31, 2019 4.50% Senior notes due 2024 $ 320.0 $ 240.0 4.75% Senior notes due 2024 79.5 61.2 8.00% Senior notes due 2024 39.7 33.8 5.20% Senior notes due 2025 335.5 250.0 7.375% Senior notes due 2025 139.2 109.2 7.20% Senior notes due 2027 37.9 29.9 $ 951.8 $ 724.1 Year Ended December 31, 2018 8.50% Senior notes due 2019 $ 237.6 $ 256.8 6.875% Senior notes due 2020 328.0 354.7 4.70% Senior notes due 2021 156.2 159.7 $ 721.8 $ 771.2 Year Ended December 31, 2017 8.50% Senior notes due 2019 $ 54.6 $ 60.1 6.875% Senior notes due 2020 100.1 105.1 4.70% Senior notes due 2021 39.4 39.3 $ 194.1 $ 204.5 (1) Excludes accrued interest paid to holders of the repurchased senior notes. Exchange Offers During 2017, we completed exchange offers to exchange our outstanding 2019 , 2020 and 2021 Notes for our 8% 2024 Notes and cash. The exchange offers resulted in the tender of $649.5 million aggregate principal amount of our outstanding notes that were settled and exchanged as follows (in millions): Aggregate Principal Amount Repurchased 8% Senior Notes Due 2024 Consideration Cash Total Consideration 8.50% Senior notes due 2019 $ 145.8 $ 81.6 $ 81.7 $ 163.3 6.875% Senior notes due 2020 129.8 69.3 69.4 138.7 4.70% Senior notes due 2021 373.9 181.1 181.4 362.5 $ 649.5 $ 332.0 $ 332.5 $ 664.5 During the year ended December 31, 2017, we recognized a pre-tax loss on the exchange offers of approximately $6.2 million . Revolving Credit Facility Effective upon closing of the Rowan Transaction, we amended our credit facility to, among other changes, increase the borrowing capacity. Previously, our credit facility had a borrowing capacity of $2.0 billion through September 2019 that declined to $1.3 billion through September 2020 and $1.2 billion through September 2022. Subsequent to the amendment, our borrowing capacity is $1.6 billion through September 2022. The credit agreement governing the Credit Facility includes an accordion feature allowing us to increase the future commitments up to an aggregate amount not to exceed $250.0 million . Advances under the credit facility bear interest at Base Rate or LIBOR plus an applicable margin rate, depending on our credit ratings. We are required to pay a quarterly commitment fee on the undrawn portion of the $1.6 billion commitment, which is also based on our credit ratings. On December 6, 2019, Moody's downgraded our corporate family rating from B3 to Caa1 and our senior unsecured notes from Caa1 to Caa2. Previously, in September 2019, Standard & Poor's downgraded our senior unsecured bonds from B to B- and our issuer rating from B- to CCC+. The applicable margin rates are 3.25% per annum for Base Rate advances and 4.25% per annum for LIBOR advances. The quarterly commitment fee is 0.75% per annum on the undrawn portion of the $1.6 billion commitment. The credit facility requires us to maintain a total debt to total capitalization ratio that is less than or equal to 60% and to provide guarantees from certain of our rig-owning subsidiaries sufficient to meet certain guarantee coverage ratios. The credit facility also contains customary restrictive covenants, including, among others, prohibitions on creating, incurring or assuming certain debt and liens (subject to customary exceptions, including a permitted lien basket that permits us to raise secured debt up to the lesser of $1 billion or 10% of consolidated tangible net worth (as defined in the credit facility)); entering into certain merger arrangements; selling, leasing, transferring or otherwise disposing of all or substantially all of our assets; making a material change in the nature of the business; paying or distributing dividends on our ordinary shares (subject to certain exceptions, including the ability to pay a quarterly dividend of $0.01 per share); borrowings, if after giving effect to any such borrowings and the application of the proceeds thereof, the aggregate amount of available cash (as defined in the credit facility) would exceed $200 million ; and entering into certain transactions with affiliates. The credit facility also includes a covenant restricting our ability to repay indebtedness maturing after September 2022, which is the final maturity date of our credit facility. This covenant is subject to certain exceptions that permit us to manage our balance sheet, including the ability to make repayments of indebtedness (i) of acquired companies within 90 days of the completion of the acquisition or (ii) if, after giving effect to such repayments, available cash is greater than $250 million and there are no amounts outstanding under the credit facility. The July 2019 tender offers discussed above were in compliance with these covenants. As of December 31, 2019 , we were in compliance in all material respects with our covenants under the credit facility. We expect to remain in compliance with our credit facility covenants during 2020 . We had no amounts outstanding under the credit facility as of December 31, 2019 and 2018 . As of January 31, 2020, we had $90 million of total outstanding borrowings under our credit facility. Our access to credit and capital markets depends on the credit ratings assigned to our debt. As a result of rating actions by credit rating agencies, we no longer maintain an investment-grade status. Our current credit ratings, and any additional actual or anticipated downgrades in our credit ratings, could limit our available options when accessing credit and capital markets, or when restructuring or refinancing our debt. In addition, future financings or refinancings are likely to involve higher borrowing costs and require more restrictive terms and covenants, which may further restrict our operations. Maturities The descriptions of our senior notes above reflect the original principal amounts issued, which have subsequently changed as a result of our tenders, repurchases, exchanges, redemptions and new debt issuances such that the maturities of our debt were as follows (in millions): Senior Notes Original Principal 2016 Tenders, Repurchases and Equity Exchange 2017 Exchange Offers and Repurchases 2018 Tender Offers, Redemption and Debt Issuance 2019 Tender Offers, Redemption and Debt Issuance Remaining Principal 6.875% due 2020 $ 900.0 $ (219.2 ) $ (229.9 ) $ (328.0 ) $ — $ 122.9 4.70% due 2021 1,500.0 (817.0 ) (413.3 ) (156.2 ) — 113.5 4.875% due 2022 (1) — — — — 620.8 620.8 3.00% Exchangeable senior notes due 2024 849.5 — — — — 849.5 4.50% due 2024 625.0 (1.7 ) — — (320.0 ) 303.3 4.75% due 2024 (1) — — — — 318.6 318.6 8.00% due 2024 — — 332.0 — (39.7 ) 292.3 5.20% due 2025 700.0 (30.7 ) — — (335.5 ) 333.8 7.375% due 2025 (1) — — — — 360.8 360.8 7.75% due 2026 — — — 1,000.0 — 1,000.0 7.20% due 2027 150.0 — — — (37.9 ) 112.1 7.875% due 2040 300.0 — — — — 300.0 5.40% due 2042 (1) — — — — 400.0 400.0 5.75% due 2044 1,025.0 (24.5 ) — — — 1,000.5 5.85% due 2044 (1) — — — — 400.0 400.0 Total $ 6,049.5 $ (1,093.1 ) $ (311.2 ) $ 515.8 $ 1,367.1 $ 6,528.1 (1) These senior notes were acquired in the Rowan Transaction. Interest Expense Interest expense totaled $428.3 million , $282.7 million and $224.2 million for the years ended December 31, 2019, 2018 and 2017 , respectively, which was net of capitalized interest of $20.9 million , $62.6 million and $72.5 million associated with newbuild rig construction and other capital projects.

Derivative Instruments

Derivative Instruments	12 Months Ended
	Dec. 31, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	DERIVATIVE INSTRUMENTS Our functional currency is the U.S. dollar. As is customary in the oil and gas industry, a majority of our revenues are denominated in U.S. dollars; however, a portion of the revenues earned and expenses incurred by certain of our subsidiaries are denominated in currencies other than the U.S. dollar. These transactions are remeasured in U.S. dollars based on a combination of both current and historical exchange rates. We use derivatives to reduce our exposure to various market risks, primarily foreign currency exchange rate risk. We maintain a foreign currency exchange rate risk management strategy that utilizes derivatives to reduce our exposure to unanticipated fluctuations in earnings and cash flows caused by changes in foreign currency exchange rates. We mitigate our credit risk relating to the counterparties of our derivatives by transacting with multiple, high-quality financial institutions, thereby limiting 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 our derivative counterparties. See " Note 16 - Supplemental Financial Information" for additional information on the mitigation of credit risk relating to counterparties of our derivatives. We do not enter into derivatives for trading or other speculative purposes. All derivatives were recorded on our consolidated balance sheets at fair value. Derivatives subject to legally enforceable master netting agreements were not offset on our consolidated balance sheets. Accounting for the gains and losses resulting from changes in the fair value of derivatives depends on the use of the derivative and whether it qualifies for hedge accounting. See "Note 1 - Description of the Business and Summary of Significant Accounting Policies" for additional information on our accounting policy for derivatives and "Note 5 - Fair Value Measurements" for additional information on the fair value measurement of our derivatives. As of December 31, 2019 and 2018 , our consolidated balance sheets included net foreign currency derivative assets of $5.4 million and liabilities of $10.7 million , respectively. All of our derivatives mature within the next 18 months. Derivatives recorded at fair value on our consolidated balance sheets as of December 31, 2019 and 2018 consisted of the following (in millions): Derivative Assets Derivative Liabilities 2019 2018 2019 2018 Derivatives Designated as Hedging Instruments Foreign currency forward contracts - current (1) $ 4.2 $ .2 $ .7 $ 8.3 Foreign currency forward contracts - non-current (2) .8 — — .4 5.0 .2 .7 8.7 Derivatives not Designated as Hedging Instruments Foreign currency forward contracts - current (1) 1.3 .4 .2 2.6 Total $ 6.3 $ .6 $ .9 $ 11.3 (1) Derivative assets and liabilities that have maturity dates equal to or less than 12 months from the respective balance sheet dates were included in other current assets and accrued liabilities and other, respectively, on our consolidated balance sheets. (2) Derivative assets and liabilities that have maturity dates greater than 12 months from the respective balance sheet dates were included in other assets and other liabilities, respectively, on our consolidated balance sheets. We utilize cash flow hedges to hedge forecasted foreign currency denominated transactions, primarily to reduce our exposure to foreign currency exchange rate risk associated with contract drilling expenses and capital expenditures denominated in various currencies. As of December 31, 2019 , we had cash flow hedges outstanding to exchange an aggregate $199.1 million for various foreign currencies, including $114.8 million for British pounds, $45.9 million for Australian dollars, $15.9 million for euros, $10.9 million for Norwegian krone, $7.9 million for Singapore dollars and $3.7 million for Brazilian reals. Gains and losses, net of tax, on derivatives designated as cash flow hedges included in our consolidated statements of operations and comprehensive loss for each of the years in the three-year period ended December 31, 2019 were as follows (in millions): Gain (Loss) Recognized in Other Comprehensive Income ("OCI") on Derivatives (Effective Portion) (Gain) Loss Reclassified from AOCI into Income (Effective Portion) (1) Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion and Amount Excluded from Effectiveness Testing) (2) 2019 2018 2017 2019 2018 2017 2019 2018 2017 Interest rate lock contracts (3) $ — $ — $ — $ 1.9 $ .2 $ .2 $ — $ — $ — Foreign currency forward contracts (4) 1.6 (9.7 ) 8.5 6.4 (1.2 ) .2 — (1.9 ) (.7 ) Total $ 1.6 $ (9.7 ) $ 8.5 $ 8.3 $ (1.0 ) $ .4 $ — $ (1.9 ) $ (.7 ) (1) Changes in the fair value of cash flow hedges are recorded in AOCI. Amounts recorded in AOCI associated with cash flow hedges are subsequently reclassified into contract drilling, depreciation or interest expense as earnings are affected by the underlying hedged forecasted transaction. (2) Gains and losses recognized in income for amounts excluded from effectiveness testing were included in other, net, in our consolidated statements of operations. As a result of our adoption of Update 2017-12 on January 1, 2019, ineffectiveness is no longer separately measured and recognized. (3) Losses on interest rate lock derivatives reclassified from AOCI into income were included in interest expense, net, in our consolidated statements of operations. (4) During the year ended December 31, 2019 , $7.3 million of losses were reclassified from AOCI into contract drilling expense and $0.9 million of gains were reclassified from AOCI into depreciation expense in our consolidated statement of operations. During the year ended December 31, 2018 , $400,000 of gains were reclassified from AOCI into contract drilling expense and $800,000 of gains were reclassified from AOCI into depreciation expense in our consolidated statement of operations. During the year ended December 31, 2017 , $1.1 million of losses were reclassified from AOCI into contract drilling expense and $900,000 of gains were reclassified from AOCI into depreciation expense in our consolidated statement of operations. We have net assets and liabilities denominated in numerous foreign currencies and use various methods to manage our exposure to foreign currency exchange rate risk. We predominantly structure our drilling contracts in U.S. dollars, which significantly reduces the portion of our cash flows and assets denominated in foreign currencies. We occasionally enter into derivatives that hedge the fair value of recognized foreign currency denominated assets or liabilities but do not designate such derivatives as hedging instruments. In these situations, a natural hedging relationship generally exists whereby changes in the fair value of the derivatives offset changes in the fair value of the underlying hedged items. As of December 31, 2019 , we held derivatives not designated as hedging instruments to exchange an aggregate $47.1 million for various foreign currencies, including $15.4 million for British pounds, $6.6 million for Israeli New shekel, $5.9 million for Norwegian krone, $4.9 million for Nigerian naira, $4.5 million for Thai baht, $4.3 million for Australian dollars and $5.5 million for other currencies. Net losses of $6.4 million and $11.8 million and gains of $10.0 million associated with our derivatives not designated as hedging instruments were included in other, net, in our consolidated statements of operations for the years ended December 31, 2019, 2018 and 2017 , respectively. As of December 31, 2019 , the estimated amount of net gains associated with derivatives, net of tax, that will be reclassified to earnings during the next 12 months was as follows (in millions): Net unrealized losses to be reclassified to contract drilling expense $ 3.4 Net realized gains to be reclassified to depreciation expense .8 Net losses to be reclassified to earnings $ 4.2

Shareholders' Equity

Shareholders' Equity	12 Months Ended
	Dec. 31, 2019
Stockholders' Equity Note [Abstract]
Shareholders' Equity	SHAREHOLDERS' EQUITY Activity in our various shareholders' equity accounts for each of the years in the three-year period ended December 31, 2019 was as follows (in millions): Shares Par Value Additional Paid-in Capital Retained Earnings AOCI Treasury Shares Non-controlling Interest BALANCE, December 31, 2016 77.6 $ 31.1 $ 6,402.2 $ 1,864.1 $ 19.0 $ (65.8 ) $ 4.4 Net loss — — — (303.7 ) — — (.5 ) Dividends paid ($0.16 per share) — — — (13.6 ) — — — Cumulative-effect reduction from adoption of ASU 2016-16 (14.1 ) Distributions to noncontrolling interests — — — — — — (6.0 ) Equity issuance in connection with Atwood Merger 33.1 13.2 757.5 — — — — Shares issued under share-based compensation plans, net 1.1 .5 (.4 ) — — (1.3 ) — Repurchase of shares — — — — — (1.9 ) — Share-based compensation cost — — 35.7 — — — — Net other comprehensive income — — — — 9.6 — — BALANCE, December 31, 2017 111.8 44.8 7,195.0 1,532.7 28.6 (69.0 ) (2.1 ) Net loss — — — (639.7 ) — — 3.1 Dividends paid ($0.16 per share) — — — (18.0 ) — — — Cumulative-effect reduction from adoption of ASU 2018-02 — — — (.8 ) .8 — — Shares issued under share-based compensation plans, net 3.4 1.4 (.6 ) — — (1.3 ) — Distributions to noncontrolling interests — — — — — — (3.6 ) Repurchase of shares — — — — — (1.9 ) — Share-based compensation cost — — 30.6 — — — — Net other comprehensive income — — — — (11.2 ) — — BALANCE, December 31, 2018 115.2 46.2 7,225.0 874.2 18.2 (72.2 ) (2.6 ) Net loss — — — (198.0 ) — — 5.8 Dividends paid ($0.04 per share) — — — (4.5 ) — — — Equity issuance in connection with the Rowan Transaction 88.0 35.2 1,367.5 — — .1 — Shares issued under share-based compensation plans, net 2.7 1.1 (1.3 ) — — (.7 ) — Repurchase of shares — — — — — (4.5 ) — Share-based compensation cost — — 37.2 — — — — Equity issuance cost — — (.6 ) — — — — Net changes in pension and other postretirement benefits — — — — (21.7 ) — — Distributions to noncontrolling interests — — — — — — (4.5 ) Net other comprehensive income — — — — 9.7 — — BALANCE, December 31, 2019 205.9 $ 82.5 $ 8,627.8 $ 671.7 $ 6.2 $ (77.3 ) $ (1.3 ) In connection with the Rowan Transaction on April 11, 2019, we issued 88.3 million Class A ordinary shares with an aggregate value of $1.4 billion . See Note 3 for additional information. On April 11, 2019, we completed our combination with Rowan and effected the Reverse Stock Split. All share and per-share amounts in these consolidated financial statements have been retrospectively adjusted to reflect the Reverse Stock Split. In October 2017, as a result of our acquisition of Atwood Oceanics, Inc. (the "Atwood Merger"), we issued 33.1 million of our Class A Ordinary shares, representing total equity consideration of $770.7 million based on a closing price of $5.83 per Class A ordinary share on October 5, 2017, the last trading day before the Merger Date. As a U.K. company governed in part by the U.K. Companies Act 2006, we cannot issue new shares (other than in limited circumstances) without being authorized by our shareholders. At our 2019 annual general meeting, our shareholders authorized the allotment of 67.6 million Class A ordinary shares (or 135.3 million Class A ordinary shares in connection with an offer by way of a rights issue or other similar issue), subject to the completion of the Rowan Transaction. Under English law, we are only able to declare dividends and return funds to our shareholders out of the accumulated distributable reserves on our statutory balance sheet. The declaration and amount of future dividends is at the discretion of our Board of Directors and will depend on our profitability, liquidity, financial condition, market outlook, reinvestment opportunities, capital requirements and other factors and restrictions our Board of Directors deems relevant. There can be no assurance that we will pay a dividend in the future. Our shareholders approved a share repurchase program at our annual shareholder meeting held in May 2018. Subject to certain provisions under English law, including the requirement of Valaris plc to have sufficient distributable reserves, we may repurchase shares up to a maximum of $500.0 million in the aggregate from one or more financial intermediaries under the program, but in no case more than 16.3 million shares. The program terminates in May 2023. As of December 31, 2019 , there had been no share repurchases under this program.

Benefit Plans

Benefit Plans	12 Months Ended
	Dec. 31, 2019
Share-based Payment Arrangement [Abstract]
Benefit Plans	SHARE BASED COMPENSATION In May 2018, our shareholders approved the 2018 Long-Term Incentive Plan (the "2018 LTIP") effective January 1, 2018, to provide for the issuance of non-vested share awards, share option awards and performance awards (collectively "awards"). The 2018 LTIP is similar to and replaces the Company's previously adopted 2012 Long-Term Incentive Plan (the “2012 LTIP”). No further awards will be granted under the 2012 LTIP. Under the 2018 LTIP, 14.8 million shares were reserved for issuance as awards to officers, non-employee directors and key employees who are in a position to contribute materially to our growth, development and long-term success. As of December 31, 2019 , there were 2.5 million shares available for issuance as awards under the 2018 LTIP. Awards may be satisfied by newly issued shares, including shares held by a subsidiary or affiliated entity, or by delivery of shares held in an affiliated employee benefit trust at the Company's discretion. In connection with the Rowan Transaction, we assumed the Amended and Restated 2013 Rowan Companies plc Incentive Plan (the "Rowan LTIP") and the non-vested share unit awards, options and share appreciation rights outstanding thereunder. As of December 31, 2019 , there were 2.3 million shares remaining available for future issuance as awards under the Rowan LTIP which may be granted to employees and other service providers who were not employed or engaged with Valaris prior to the Rowan Transaction. In connection with the Atwood Merger, we assumed Atwood’s Amended and Restated 2007 Long-Term Incentive Plan (the “Atwood LTIP”, and together with the 2018 LTIP and the Rowan LTIP, the "LTIP Plans") and the options outstanding thereunder. As of December 31, 2019 , there were 100,000 shares remaining available for future issuance as awards under the Atwood LTIP, which may be granted to employees and other service providers who were not employed or engaged with Valaris prior to the Atwood Merger. Non-Vested Share Awards, Cash-Settled Awards and Non-employee Director Deferred Awards Grants of share awards and share units (collectively "share awards") and share units to be settled in cash ("cash-settled awards"), generally vest at rates of 20% or 33% per year, as determined by a committee of the Board of Directors at the time of grant. Additionally, non-employee directors may annually elect to receive deferred share awards. Deferred share awards vest at the earlier of the first anniversary of the grant date or the next annual meeting of shareholders following the grant but are not settled until the director terminates service from the Board. Deferred share awards are settled in cash, shares or a combination thereof at the discretion of the Compensation Committee. During 2019 , no cash-settled awards were granted while 4.5 million share unit awards were granted to our employees and non-employee directors pursuant to the LTIP Plans. Our non-vested share awards have voting and dividend rights effective on the date of grant, and our non-vested share units have dividend rights effective on the date of grant. Compensation expense for share awards is measured at fair value on the date of grant and recognized on a straight-line basis over the requisite service period (usually the vesting period). Compensation expense for cash-settled awards is remeasured each quarter with a cumulative adjustment to compensation cost during the period based on changes in our share price. Our compensation cost is reduced for forfeited awards in the period in which the forfeitures occur. The following table summarizes share award and cash-settled award compensation expense recognized during each of the years in the three-year period ended December 31, 2019 (in millions): 2019 2018 2017 Contract drilling $ 22.1 $ 18.9 $ 18.3 General and administrative 17.4 14.5 14.5 39.5 33.4 32.8 Tax benefit (2.5 ) (2.8 ) (4.8 ) Total $ 37.0 $ 30.6 $ 28.0 The following table summarizes the value of share awards and cash-settled awards granted and vested during each of the years in the three-year period ended December 31, 2019 : Share Awards Cash-Settled Awards 2019 2018 2017 2019 2018 2017 Weighted-average grant-date fair value of share awards granted (per share) $ 11.50 $ 24.62 $ 31.48 $ — $ 21.35 $ 25.08 Total fair value of share awards vested during the period (in millions) $ 17.7 $ 7.5 $ 8.2 $ 3.5 $ 9.9 $ 3.9 The following table summarizes share awards and cash-settled awards activity for the year ended December 31, 2019 (shares in thousands): Share Awards Cash-settled Awards Awards Weighted-Average Grant-Date Fair Value Awards Weighted-Average Grant-Date Fair Value Share awards and cash-settled awards as of December 31, 2018 2,017 $ 31.36 1,279 $ 29.20 Granted 4,460 11.50 — — Rowan share awards assumed 2,329 15.88 — — Vested (1,519 ) 10.53 (453 ) 7.97 Forfeited (854 ) 8.87 (129 ) 11.58 Share awards and cash-settled awards as of December 31, 2019 6,433 $ 19.89 697 $ 46.28 As of December 31, 2019 , there was $115.9 million of total unrecognized compensation cost related to share awards, which is expected to be recognized over a weighted-average period of 1.7 years. Share Appreciation Rights Share Appreciation Rights ("SARs") granted to employees generally become exercisable in 33% increments over a three-year period and, to the extent not exercised, expire on the tenth anniversary of the date of grant. The exercise price of SARs granted under the Rowan LTIP equals the excess of the market value of the underlying shares on the date of exercise over the market value of the shares on date of grant multiplied by the number of shares covered by the SAR. The Company intends to share-settle any exercises of SARs and has therefore accounted for SARs as equity awards. As of December 31, 2019 , SARs granted to purchase 530,923 shares with a weighted-average exercise price of $50.70 were outstanding under the Rowan LTIP. No SARs have been granted since 2010 under the Rowan LTIP, and there was no unrecognized compensation cost related to SARs as of December 31, 2019 . Share Option Awards Share option awards ("options") granted to employees generally become exercisable in 25% increments over a four-year period or 33% increments over a three-year period or 100% after a four - year period and, to the extent not exercised, expire on either the seventh or tenth anniversary of the date of grant. The exercise price of options granted under the 2018 LTIP equals the market value of the underlying shares on the date of grant. As of December 31, 2019 , options granted to purchase 375,701 shares with a weighted-average exercise price of $52.77 were outstanding under the Company LTIPs. Excluding options assumed under the Atwood LTIP, no options have been granted since 2011, and there was no unrecognized compensation cost related to options as of December 31, 2019 . Performance Awards Under the Company LTIPs, performance awards may be issued to our senior executive officers. The 2019 performance awards are subject to achievement of specified performance goals based on both relative and absolute total shareholder return ("TSR"), while the 2017 and 2018 performance awards are subject to achievement of specified performance goals based on relative TSR and relative return on capital employed ("ROCE") as compared to a specified peer group. The performance goals are determined by a committee or subcommittee of the Board of Directors. Awards are payable in either Valaris shares or cash upon attainment of relative TSR and ROCE performance goals. Performance awards granted since 2017 are payable in cash. Performance awards generally vest at the end of a three -year measurement period based on attainment of performance goals. Our performance awards granted during 2017, 2018 and 2019 are classified as liability awards, all with compensation expense recognized over the requisite service period. The estimated probable outcome of attainment of the specified performance goals is based primarily on relative performance over the requisite performance period. Any subsequent changes in this estimate are recognized as a cumulative adjustment to compensation cost in the period in which the change in estimate occurs. The aggregate grant-date fair value of performance awards granted during 2019, 2018 and 2017 totaled $6.7 million . The aggregate fair value of performance awards vested during 2019, 2018 and 2017 totaled $2.2 million , $0.7 million and $2.9 million , respectively. During the years ended December 31, 2019, 2018 and 2017 , we recognized $3.2 million , $8.2 million and $8.4 million of compensation expense for performance awards, respectively, which was included in general and administrative expense in our consolidated statements of operations. As of December 31, 2019 , there was $0.8 million of total unrecognized compensation cost related to unvested performance awards, which is expected to be recognized over a weighted-average period of 1.1 years. Savings Plans We have savings plans, (the Ensco Savings Plan, the Ensco Multinational Savings Plan, the Ensco Limited Retirement Plan, the Rowan Companies, Inc. Savings & Investment Plan (the "Rowan Savings Plan"), the RDIS International Savings Plan and the Rowan Drilling UK Pension Scheme), which cover eligible employees as defined within each plan. The Ensco Savings Plan and the Rowan Savings Plan include a 401(k) savings plan feature, which allows eligible employees to make tax-deferred contributions to the plans. The Ensco Limited Retirement Plan and the Rowan Drilling UK Pension Scheme also allows eligible employees to make tax-deferred contributions to the plan. Contributions made to the Ensco Multinational Savings Plan and the RDIS International Savings Plan may or may not qualify for tax deferral based on each plan participant's local tax requirements. We generally make matching cash contributions to the plans. The legacy Ensco plans match 100% of the amount contributed by the employee up to a maximum of 5% of eligible salary, where the legacy Rowan plans also provide up to a 5% match of eligible salary; however, depending on the plan and the tier, the match percentage could vary. Matching contributions totaled $18.7 million , $14.4 million and $12.2 million for the years ended December 31, 2019, 2018 and 2017 , respectively. Any additional discretionary contributions made into the plans require approval of the Board of Directors and are generally paid in cash. As of January 1, 2019, the plans were modified such that all previous, current and future employer contributions become 100% vested. We have 1.0 million shares reserved for issuance as matching contributions under the Ensco Savings Plan.

Pension and Other Post-retireme

Pension and Other Post-retirement Benefits	12 Months Ended
	Dec. 31, 2019
Retirement Benefits [Abstract]
Pension and Other Post-retirement Benefits	Pension and Other Post-retirement Benefits Prior to the Rowan Transaction, Rowan established various defined-benefit pension plans and a post-retirement health and life insurance plan that provide benefits upon retirement for certain full-time employees. The defined-benefit pension plans include: (1) the Rowan Pension Plan; (2) Restoration Plan of Rowan Companies, Inc. (the “Rowan SERP”); (3) the Norway Onshore Plan; and (4) the Norway Offshore Plan. The Retiree Life & Medical Supplemental Plan of Rowan Companies, Inc. (the “Retiree Medical Plan”) provides post-retirement health and life insurance benefits. On November 27, 2017, Rowan purchased annuities to cover post-65 retiree medical benefits for current retirees as of the purchase date. The annuity purchase settled post-65 medical benefits (i.e., Health Reimbursement Account, or “HRA”, amounts) for affected participants, with the insurer taking responsibility for all benefit payments on and after January 1, 2019. As a result of the Rowan Transaction, we assumed these plans and obligations, which were remeasured as of the Transaction Date. Each of the plans has a benefit obligation that exceeds the fair value of plan assets. As of the Transaction Date, the net projected benefit obligations totaled $239.3 million , of which $19.2 million was classified as current. The current and non-current portions of the net benefit obligations are included in accrued liabilities and other liabilities in our consolidated balance sheet, respectively. The most significant of the assumed plans is the Rowan Pension Plan, which had a net projected benefit obligation of $202.1 million . Prior to the Transaction Date, Rowan amended the Rowan Pension Plan to freeze the plan as to any future benefit accruals. As a result, eligible employees no longer receive pay credits in the pension plan and newly hired employees are not eligible to participate in the pension plan. The following table presents the changes in benefit obligations and plan assets for the year ended December 31, 2019 and the funded status and weighted-average assumptions used to determine the benefit obligation at year end (dollars in millions): 2019 Pension Benefits Other Benefits Total Projected benefit obligation: Balance, April 11 $ 800.1 $ 15.9 $ 816.0 Interest cost 21.3 0.4 21.7 Service cost 1.5 — 1.5 Actuarial loss 43.8 0.2 44.0 Benefits paid (34.1 ) (0.4 ) (34.5 ) Foreign currency adjustments (0.2 ) — (0.2 ) Balance, December 31 $ 832.4 $ 16.1 $ 848.5 Plan assets Fair value, April 11 $ 576.8 $ — $ 576.8 Actual return 43.6 — 43.6 Employer contributions 12.8 — 12.8 Benefits paid (34.1 ) — (34.1 ) Foreign currency adjustments (0.2 ) — (0.2 ) Fair value, December 31 $ 598.9 — $ 598.9 Net benefit liabilities $ 233.5 $ 16.1 $ 249.6 Amounts recognized in consolidated balance sheet: Accrued liabilities $ (1.4 ) $ (1.5 ) $ (2.9 ) Other liabilities (long-term) (232.1 ) (14.6 ) (246.7 ) Net benefit liabilities $ (233.5 ) $ (16.1 ) $ (249.6 ) Accumulated contributions in excess of (less than) net periodic benefit cost $ (206.2 ) $ (15.9 ) $ (222.1 ) Amounts not yet reflected in net periodic benefit cost: Actuarial loss $ (27.3 ) $ (0.2 ) $ (27.5 ) Total accumulated other comprehensive loss (27.3 ) (0.2 ) (27.5 ) Net benefit liabilities $ (233.5 ) $ (16.1 ) $ (249.6 ) Weighted-average assumptions: Discount rate 3.16 % 3.06 % Rate of compensation increase — % — % The projected benefit obligations for pension benefits in the preceding table reflect the actuarial present value of benefits accrued based on services rendered to date and include the estimated effect of future salary increases. The accumulated benefit obligations, which are presented below for all plans in the aggregate at December 31, 2019 , are based on services rendered to date, but exclude the effect of future salary increases (in millions): 2019 Accumulated benefit obligation $ 844.3 The components of net periodic pension cost and the weighted-average assumptions used to determine net periodic pension cost were as follows (dollars in millions): April 11, 2019 - December 31, 2019 Service cost (1) $ 1.5 Interest cost (2) 21.3 Expected return on plan assets (2) (27.1 ) Net periodic pension cost (benefit) $ (4.3 ) Discount rate 3.82 % (1) Included in contract drilling and general and administrative expense in our consolidated statements of operations. (2) Included in other, net, in our consolidated statements of operations. The pension plans' investment objectives for fund assets are: to achieve over the life of the plans a return equal to the plans' expected investment return or the inflation rate plus 3%, whichever is greater, to invest assets in a manner such that contributions are minimized and future assets are available to fund liabilities, to maintain liquidity sufficient to pay benefits when due, and to diversify among asset classes so that assets earn a reasonable return with an acceptable level of risk. The plans employ several active managers with proven long-term records in their specific investment discipline. Target allocations among asset categories and the fair value of each category of plan assets as of December 31, 2019 , classified by level within the US GAAP fair value hierarchy are presented below. The plans will reallocate assets in accordance with the allocation targets, after giving consideration to the expected level of cash required to pay current benefits and plan expenses (dollars in millions): Target range Total Quoted prices in active markets for identical assets (Level 1) Significant observable inputs (Level 2) Significant unobservable inputs (Level 3) December 31, 2019 Equities: 53% to 69% U.S. large cap 22% to 28% $ 148.9 $ — $ 148.9 $ — U.S. small cap 4% to 10% 41.1 — 41.1 — International all cap 21% to 29% 152.4 — 152.4 — International small cap 2% to 8% 34.7 — 34.7 — Real estate equities 0% to 13% 54.9 — 54.9 — Fixed income: 25% to 35% Cash and equivalents 0% to 10% 6.5 6.5 — — Aggregate 9% to 19% 76.7 — 76.7 — Core plus 9% to 19% 77.6 77.6 — — Group annuity contracts 6.1 — 6.1 — Total $ 598.9 $ 84.1 $ 514.8 $ — Assets in the U.S. equities category include investments in common and preferred stocks (and equivalents such as American Depository Receipts and convertible bonds) and may be held through separate accounts, commingled funds or an institutional mutual fund. Assets in the international equities category include investments in a broad range of international equity securities, including both developed and emerging markets, and may be held through a commingled or institutional mutual fund. The real estate category includes investments in pooled and commingled funds whose objectives are diversified equity investments in income-producing properties. Each real estate fund is intended to provide broad exposure to the real estate market by property type, geographic location and size and may invest internationally. Securities in both the aggregate and core plus fixed income categories include U.S. government, corporate, mortgage- and asset-backed securities and Yankee bonds, and both categories target an average credit rating of “A” or better at all times. Individual securities in the aggregate fixed income category must be investment grade or above at the time of purchase, whereas securities in the core plus category may have a rating of “B” or above. Additionally, the core plus category may invest in non-U.S. securities. Assets in the aggregate and core plus fixed income categories are held primarily through a commingled fund and an institutional mutual fund, respectively. Group annuity contracts are invested in a combination of equity, real estate, bond and other investments in connection with a pension plan in Norway. The following is a description of the valuation methodologies used for the pension plan assets as of December 31, 2019 : • Fair values of all U.S. equity securities, the international all cap equity securities and aggregate fixed income securities categorized as Level 2 were held in commingled funds which were valued daily based on a net asset value. • Fair value of international small cap equity securities categorized as Level 2 were held in a limited partnership fund which was valued monthly based on a net asset value. • The real estate equities categorized as Level 2 were held in two accounts (a commingled fund and a limited partnership). The assets in the commingled fund were valued monthly based on a net asset value and the assets in the limited partnership were valued quarterly based on a net asset value. • Cash and equivalents categorized as Level 1 were valued at cost, which approximates fair value. • Fair value of mutual fund investments in core plus fixed income securities categorized as Level 1 were based on quoted market prices which represent the net asset value of shares held. To develop the expected long-term rate of return on assets assumption, we considered the current level of expected returns on risk-free investments (primarily government bonds), the historical level of the risk premium associated with the plans’ other asset classes and the expectations for future returns of each asset class. The expected return for each asset class was then weighted based upon the current asset allocation to develop the expected long-term rate of return on assets assumption for the plans, which was 6.48% at December 31, 2019 . We currently expect to contribute approximately $35.7 million to our pension plans in 2020 and to directly pay other post-retirement benefits of approximately $1.5 million . Estimated future annual benefit payments from plan assets are presented below. Such amounts are based on existing benefit formulas and include the effect of future service (in millions): Pension Benefits Other Post-Retirement Benefits Year ended December 31, 2020 $ 45.0 $ 1.5 2021 45.0 1.4 2022 44.6 1.3 2023 44.2 1.3 2024 43.9 1.3 2025 through 2029 213.6 5.3

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2019
Components of Income Tax Expense (Benefit), Continuing Operations [Abstract]
Income Taxes	INCOME TAXES We generated profits of $39.0 million , losses of $115.1 million and profits of $6.3 million from continuing operations before income taxes in the U.S. and losses of $102.8 million , $423.8 million and $202.3 million from continuing operations before income taxes in non-U.S. jurisdictions for the years ended December 31, 2019 , 2018 and 2017 , respectively. The following table summarizes components of our provision for income taxes from continuing operations for each of the years in the three-year period ended December 31, 2019 (in millions): 2019 2018 2017 Current income tax expense (benefit): U.S. $ 31.3 $ (19.9 ) $ (2.2 ) Non-U.S. 73.2 52.9 56.4 104.5 33.0 54.2 Deferred income tax expense: U.S. 19.7 52.9 36.0 Non-U.S. 4.2 3.7 19.0 23.9 56.6 55.0 Total income tax expense $ 128.4 $ 89.6 $ 109.2 U.S. Tax Reform U.S. tax reform was enacted on December 22, 2017 and introduced significant changes to U.S. income tax law, including a reduction in the statutory income tax rate from 35% to 21% effective January 1, 2018, a one-time transition tax on deemed repatriation of deferred foreign income, a base erosion anti-abuse tax that effectively imposes a minimum tax on certain payments to non-U.S. affiliates, new and revised rules relating to the current taxation of certain income of foreign subsidiaries and revised rules associated with limitations on the deduction of interest. Due to the timing of the enactment of U.S. tax reform and the complexity involved in applying its provisions, we made reasonable estimates of its effects and recorded such amounts in our consolidated financial statements as of December 31, 2017 on a provisional basis. Throughout 2018, we continued to analyze applicable information and data, interpret rules and guidance issued by the U.S. Treasury Department and Internal Revenue Service, and make adjustments to the provisional amounts as provided for in Staff Accounting Bulletin No. 118. The U.S. Treasury Department continued finalizing rules associated with U.S. tax reform during 2018 and 2019. During 2019 , we recognized a tax expense of $13.8 million associated with final rules issued related to U.S. tax reform. During 2018 , we recognized a tax benefit of $11.7 million associated with the one-time transition tax on deemed repatriation of the deferred foreign income of our U.S. subsidiaries. We recognized a net tax expense of $16.5 million during 2017 in connection with enactment of U.S. tax reform, consisting of a $38.5 million tax expense associated with the one-time transition tax on deemed repatriation of the deferred foreign income of our U.S. subsidiaries, a $17.3 million tax expense associated with revisions to rules over the taxation of income of foreign subsidiaries, a $20.0 million tax benefit resulting from the re-measurement of our deferred tax assets and liabilities as of December 31, 2017 to reflect the reduced tax rate and a $19.3 million tax benefit resulting from adjustments to the valuation allowance on deferred tax assets. Deferred Taxes The following table summarizes significant components of deferred income tax assets and liabilities as of December 31, 2019 and 2018 (in millions): 2019 2018 Deferred tax assets : Net operating loss carryforwards $ 1,546.7 $ 148.4 Net capital loss carryforwards 998.0 — Foreign tax credits 142.9 123.6 Interest limitation carryforwards 41.5 40.2 Premiums on long-term debt — 23.8 Employee benefits, including share-based compensation 73.9 15.4 Deferred revenue 0.1 10.3 Other 11.6 14.5 Total deferred tax assets 2,814.7 376.2 Valuation allowance (2,588.7 ) (316.0 ) Net deferred tax assets 226.0 60.2 Deferred tax liabilities : Property and equipment (156.0 ) (54.5 ) Net discounts on long-term debt (49.5 ) — Deferred U.S. tax on foreign income (36.7 ) (31.5 ) Other (23.7 ) (9.0 ) Total deferred tax liabilities (265.9 ) (95.0 ) Net deferred tax asset (liability) $ (39.9 ) $ (34.8 ) The realization of substantially all of our deferred tax assets is dependent upon generating sufficient taxable income during future periods in various jurisdictions in which we operate. Realization of certain of our deferred tax assets is not assured. We recognize a valuation allowance for deferred tax assets when it is more-likely-than-not that the benefit from the deferred tax asset will not be realized. The amount of deferred tax assets considered realizable could increase or decrease in the near-term if our estimates of future taxable income change. As of December 31, 2019 , we had deferred tax assets of $142.9 million for U.S. foreign tax credits (“FTCs”), $1.5 billion related to $6.4 billion of net operating loss (“NOL”) carryforwards and $41.5 million for U.S. interest limitation carryforwards, which can be used to reduce our income taxes payable in future years. The FTCs expire between 2022 and 2029 . NOL carryforwards, which were generated in various jurisdictions worldwide, include $5.6 billion that do not expire and $773.0 million that will expire, if not utilized, between 2020 and 2037 . Deferred tax assets for NOL carryforwards at December 31, 2019 includes $1.3 billion acquired in the Rowan Transaction, substantially all of which pertains to NOL in Luxembourg. U.S. interest limitation carryforwards do not expire. Due to the uncertainty of realization, we have a $1.5 billion valuation allowance on FTC, NOL carryforwards and U.S. interest limitation carryforwards. During 2019 , we completed certain restructuring transactions that generated substantial U.S. capital gains and losses. As of December 31, 2019 , we had recognized a deferred tax asset of $998 million associated with the net capital loss arising from these transactions. Based on our current assessment, this deferred tax asset is subject to a full valuation allowance because we more-likely-than-not will be unable to realize a future benefit from it. Effective Tax Rate Valaris plc, our parent company, is domiciled and resident in the U.K. Our subsidiaries conduct operations and earn income in numerous countries and are subject to the laws of taxing jurisdictions within those countries. The income of our non-U.K. subsidiaries is generally not subject to U.K. taxation. Income tax rates imposed in the tax jurisdictions in which our subsidiaries conduct operations vary, as does the tax base to which the rates are applied. In some cases, tax rates may be applicable to gross revenues, statutory or negotiated deemed profits or other bases utilized under local tax laws, rather than to net income. Our drilling rigs frequently move from one taxing jurisdiction to another to perform contract drilling services. In some instances, the movement of drilling rigs among taxing jurisdictions will involve the transfer of ownership of the drilling rigs among our subsidiaries. As a result of frequent changes in the taxing jurisdictions in which our drilling rigs are operated and/or owned, changes in profitability levels and changes in tax laws, our annual effective income tax rate may vary substantially from one reporting period to another. In periods of declining profitability, our income tax expense may not decline proportionally with income, which could result in higher effective income tax rates. Further, we will continue to incur income tax expense in periods in which we operate at a loss. Our consolidated effective income tax rate on continuing operations for each of the years in the three-year period ended December 31, 2019 , differs from the U.K. statutory income tax rate as follows: 2019 2018 2017 U.K. statutory income tax rate 19.0 % 19.0 % 19.2 % Non-U.K. taxes (280.9 ) (18.0 ) (40.4 ) Bargain purchase gain 189.7 (.2 ) 13.8 Valuation allowance (145.1 ) (16.9 ) (18.0 ) Debt repurchases 48.7 (1.6 ) (2.8 ) Asset impairments (31.0 ) (1.4 ) (17.1 ) U.S. tax reform (21.6 ) 2.2 (8.4 ) Restructuring transaction 7.9 1.7 — Other 12.0 (1.4 ) (2.0 ) Effective income tax rate (201.3 )% (16.6 )% (55.7 )% Our 2019 consolidated effective income tax rate includes $2.3 million associated with the impact of various discrete tax items, including $28.3 million of tax expense associated with final rules related to U.S. tax reform, gains on repurchase of debt and settlement proceeds, partially offset by $26.0 million of tax benefit related to restructuring transactions, changes in liabilities for unrecognized tax benefits associated with tax positions taken in prior years and other resolutions of prior year tax matters and rig sales. Our 2018 consolidated effective income tax includes the impact of various discrete tax items, including $46.0 million of tax benefit associated with the utilization of foreign tax credits subject to a valuation allowance, the transition tax on deemed repatriation of the deferred foreign income of our U.S. subsidiaries and a restructuring transaction, partially offset by $21.0 million of tax expense related to recovery of certain costs associated with an ongoing legal matter, repurchase and redemption of senior notes, unrecognized tax benefits associated with tax positions taken in prior years and rig sales. Our 2017 consolidated effective income tax rate includes $32.2 million associated with the impact of various discrete tax items, including $16.5 million of tax expense associated with U.S. tax reform and $15.7 million of tax expense associated with the exchange offers and debt repurchases, rig sales, a restructuring transaction, settlement of a previously disclosed legal contingency, the effective settlement of a liability for unrecognized tax benefits associated with a tax position taken in prior years and other resolutions of prior year tax matters. Excluding the impact of the aforementioned discrete tax items, our consolidated effective income tax rates for the years ended December 31, 2019 , 2018 and 2017 were (14.6)% , (24.8)% and (96.0)% . The changes in our consolidated effective income tax rate, excluding discrete tax items, during the three-year period result primarily from U.S. tax reform and changes in the relative components of our earnings from the various taxing jurisdictions in which our drilling rigs are operated and/or owned and differences in tax rates in such taxing jurisdictions. As discussed in Note 7, on February 3, 2020, Rowan and RCI transferred substantially all their assets and liabilities to Valaris plc and Valaris plc became the obligor on the Rowan Notes. We expect to recognize a deferred tax benefit ranging from $40 million to $60 million during the first quarter of 2020 in connection with this transaction. Unrecognized Tax Benefits Our tax positions are evaluated for recognition using a more-likely-than-not threshold, and those tax positions requiring recognition are measured as the largest amount of tax benefit that is greater than 50% likely of being realized upon effective settlement with a taxing authority that has full knowledge of all relevant information. As of December 31, 2019 , we had $296.7 million of unrecognized tax benefits, of which $264.2 million was included in other liabilities on our consolidated balance sheet and the remaining $32.5 million , which is associated with a tax position taken in tax years with NOL carryforwards, was presented as a reduction of deferred tax assets. As of December 31, 2018 , we had $143.0 million of unrecognized tax benefits, of which $136.5 million was included in other liabilities on our consolidated balance sheet and the remaining $6.5 million , which is associated with a tax position taken in tax years with NOL carryforwards, was presented as a reduction of deferred tax assets. If recognized, $253.9 million of the $296.7 million unrecognized tax benefits as of December 31, 2019 would impact our consolidated effective income tax rate. A reconciliation of the beginning and ending amount of unrecognized tax benefits for the years ended December 31, 2019 and 2018 is as follows (in millions): 2019 2018 Balance, beginning of year $ 143.0 $ 147.6 Increases in unrecognized tax benefits as a result of the Rowan Transaction 149.9 — Increases in unrecognized tax benefits as a result of tax positions taken during the current year 17.8 6.5 Impact of foreign currency exchange rates (.3 ) (5.0 ) Lapse of applicable statutes of limitations (4.4 ) (4.5 ) Increase in unrecognized tax benefits as a result of tax positions taken during prior years 1.1 2.5 Decreases in unrecognized tax benefits as a result (2.4 ) (3.8 ) Settlements with taxing authorities (8.0 ) (.3 ) Balance, end of year $ 296.7 $ 143.0 Several of our rigs are owned by subsidiaries in Switzerland that are subject to a special finance taxation regime under Swiss income tax rules. Swiss federal and cantonal governments have enacted tax legislation (“Swiss tax reform”) effective January 1, 2020. Under Swiss tax reform, the finance taxation regime has been abolished but our Swiss subsidiaries will remain subject to the finance taxation regime through December 31, 2021 and transition to deriving income tax based on net income beginning January 1, 2022. There are various uncertainties relating to the application of Swiss tax reform to finance taxation regime taxpayers, the most prominent of which is the determination of the Swiss tax basis of property and equipment. After considering these uncertainties and all information currently available, we have concluded the tax basis of the property and equipment of our Swiss subsidiaries will more likely than not approximate its U.S. GAAP basis and, accordingly, we have not recognized deferred taxes. As the Swiss tax authorities further clarify the application of Swiss tax reform to finance taxation regime taxpayers, we may recognize deferred tax adjustments and they may have a material effect on our consolidated financial statements. Accrued interest and penalties totaled $58.9 million and $40.5 million as of December 31, 2019 and 2018 , respectively, and were included in other liabilities on our consolidated balance sheets. We recognized a net expense of $5.7 million , $1.9 million and $4.4 million associated with interest and penalties during the years ended December 31, 2019 , 2018 , and 2017 respectively. Interest and penalties are included in current income tax expense in our consolidated statements of operations. Three of our subsidiaries file U.S. tax returns and the tax returns of one or more of these subsidiaries is under exam for years 2009 to 2012 and for 2014 and subsequent years. None of these examinations are expected to have an impact on the Company's consolidated results of operations and cash flows. Tax years as early as 2005 remain subject to examination in the other major tax jurisdictions in which we operated. Statutes of limitations applicable to certain of our tax positions lapsed during 2019, 2018 and 2017 , resulting in net income tax benefits, inclusive of interest and penalties, of $5.3 million , $5.3 million and $1.1 million , respectively. Absent the commencement of examinations by tax authorities, statutes of limitations applicable to certain of our tax positions will lapse during 2020 . Therefore, it is reasonably possible that our unrecognized tax benefits will decline during the next 12 months by $800,000 , inclusive of $550,000 of accrued interest and penalties, all of which would impact our consolidated effective income tax rate if recognized. Recent Tax Assessments During 2019 , the Luxembourg tax authorities issued aggregate tax assessments totaling approximately €142.0 million (approximately $159.0 million converted using the current period-end exchange rates) related to tax years 2014, 2015 and 2016 for several of Rowan's Luxembourg subsidiaries, which assessments accrue interest at the rate of 7.2% per annum. We may make a payment to the Luxembourg tax authorities in advance of the final resolution of these assessments. Although the outcome of such assessments cannot be predicted with certainty, unfavorable outcomes could have a material adverse effect on our financial position, operating results and cash flows. We have recorded a $104 million liability for these assessments as of December 31, 2019 . During 2019 , the Australian tax authorities issued aggregate tax assessments totaling approximately A$101 million (approximately $70.9 million converted at current period-end exchange rates) plus interest related to the examination of certain of our tax returns for the years 2011 through 2016. During the third quarter of 2019, we made a A$42 million payment (approximately $29 million at then-current exchange rates) to the Australian tax authorities to litigate the assessment. We have recorded a $15 million liability for these assessments as of December 31, 2019 . We believe our tax returns are materially correct as filed, and we are vigorously contesting these assessments. Although the outcome of such assessments and related administrative proceedings cannot be predicated with certainty, we do not expect these matters to have a material adverse effect on our financial position, operating results and cash flows. Undistributed Earnings Dividend income received by Valaris plc from its subsidiaries is exempt from U.K. taxation. We do not provide deferred taxes on undistributed earnings of certain subsidiaries because our policy and intention is to reinvest such earnings indefinitely. Each of the subsidiaries for which we maintain such policy has sufficient net assets, liquidity, contract backlog and/or other financial resources available to meet operational and capital investment requirements, which allows us to continue to maintain our policy of reinvesting the undistributed earnings indefinitely. As of December 31, 2019 , the aggregate undistributed earnings of the subsidiaries for which we maintain a policy and intention to reinvest earnings indefinitely totaled $289.0 million . Should we make a distribution from these subsidiaries in the form of dividends or otherwise, we would be subject to additional income taxes. The unrecognized deferred tax liability related to these undistributed earnings was not practicable to estimate as of December 31, 2019

Commitments And Contingencies

Commitments And Contingencies	12 Months Ended
	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments And Contingencies	COMMITMENTS AND CONTINGENCIES Capital Commitments The following table summarizes the estimated timing of our remaining contractual payments of our rigs under construction as of December 31, 2019 for our rigs under construction and (in millions): 2020 2021 2022 Thereafter Total (1) VALARIS DS-13 (2) $ — $ 83.9 $ — $ — $ 83.9 VALARIS DS-14 (2) — — 165.0 — 165.0 $ — $ 83.9 $ 165.0 $ — $ 248.9 (1) Total commitments are based on fixed-price shipyard construction contracts, exclusive of costs associated with project management, commissioning and systems integration testing. Total commitments also exclude holding costs and interest. Based on our current projections, excluding integration-related capital expenditures, we expect capital expenditures during 2020 to approximate $ 160 million for newbuild construction, rig enhancement projects and minor upgrades and improvements. Approximately $30 million of our projected capital expenditures is reimbursable by our customers. Depending on market conditions and opportunities, we may reduce our planned expenditures or make additional capital expenditures to upgrade rigs for customer requirements or acquire additional rigs. (2) During the third quarter of 2019, we entered into amendments to our construction agreements with the shipyard for VALARIS DS-13 and VALARIS DS-14 to provide for, among other things, two-year extensions of the delivery date of each rig in exchange for payment of all accrued holding costs through March 31, 2019, totaling approximately $23 million . The new delivery dates for the VALARIS DS-13 and VALARIS DS-14 are September 30, 2021 and June 30, 2022, respectively. We can elect to request earlier delivery in certain circumstances. The interest rate on the final milestone payments increased from 5% to 7% per annum from October 1, 2019, for the VALARIS DS-13, and from July 1, 2020, for the VALARIS DS-14, until the actual delivery dates. The final milestone payments and interest are due at the new delivery dates (or, if accelerated, the actual delivery dates) and are estimated to be approximately $313.3 million in aggregate for both rigs, inclusive of interest, assuming we take delivery on the new delivery dates. In lieu of making the final milestone payments, we have the option to take delivery of the rigs and issue a promissory note for each rig to the shipyard owner for the amount due. If we issue the promissory note to the shipyard owner, we would also be required to provide a guarantee from Valaris plc. Upon delivery, the remaining milestone payments and accrued interest thereon may be financed through a promissory note with the shipyard for each rig. The promissory notes will bear interest at a rate of 9% per annum with a maturity date of December 30, 2022 and will be secured by a mortgage on each respective rig. The remaining milestone payments for VALARIS DS-13 and VALARIS DS-14 are included in the table above in the period in which we expect to take delivery of the rig. However, we may elect to execute the promissory notes and defer payment until December 2022. DSA Dispute On January 4, 2016, Petrobras sent a notice to us declaring the drilling services agreement with Petrobras (the "DSA") for VALARIS DS-5, a drillship ordered from Samsung Heavy Industries, a shipyard in South Korea ("SHI"), void effective immediately, reserving its rights and stating its intention to seek any restitution to which it may be entitled. The previously disclosed arbitral hearing on liability related to the matter was held in March 2018. Prior to the arbitration tribunal issuing its decision, we and Petrobras agreed in August 2018 to a settlement of all claims relating to the DSA. No payments were made by either party in connection with the settlement agreement. The parties agreed to normalize business relations and the settlement agreement provides for our participation in current and future Petrobras tenders on the same basis as all other companies invited to these tenders. No losses were recognized during 2018 with respect to this settlement as all disputed receivables with Petrobras related to the DSA were fully reserved in 2015. In April 2016, we initiated separate arbitration proceedings in the U.K. against SHI for the losses incurred in connection with the foregoing Petrobras arbitration and certain other losses relating to the DSA. In January 2018, the arbitration tribunal for the SHI matter issued an award on liability fully in our favor. The January 2018 arbitration award provides that SHI is liable to us for $10 million or damages that we can prove. We submitted our claim for damages to the tribunal, and the arbitral hearing on damages owed to us by SHI took place during the first quarter of 2019. In May 2019, the arbitration tribunal for the SHI matter awarded us $180.0 million in damages. Further, we are entitled to claim interest on this award and costs incurred in connection with this matter. In June 2019, we and SHI filed separate applications with the English High Court to seek leave to appeal the damages awarded. In December 2019, the English High Court denied the parties’ applications for leave to appeal the tribunal’s $180.0 million damages award. Following this decision, the parties reached an agreement and SHI paid us $200.0 million in cash. Collection of this payment resulted in the recognition of a gain of the same amount, which is included in other, net, in our consolidated statement of operations for the year ended December 31, 2019 . This payment, along with the previously disclosed settlement and normalization of our business relationship with Petrobras, concludes our dispute surrounding VALARIS DS-5. Indonesian Well-Control Event In July 2019, a well being drilled offshore Indonesia by one of our jackup rigs experienced a well-control event requiring the cessation of drilling activities. The operator could seek to terminate the contract under certain circumstances. If this drilling contract were to be terminated for cause, it would result in an approximate $8.5 million decrease in our backlog as of December 31, 2019 . Indonesian authorities have initiated a preliminary investigation into the event and have contacted the customer, us and other parties involved in drilling the well for additional information. We are cooperating with the Indonesian authorities. We cannot predict the scope or ultimate outcome of this preliminary investigation or whether the Indonesian authorities will open a full investigation into our involvement in this matter. If the Indonesian authorities determine that we violated local laws in connection with this matter, we could be subject to penalties including environmental or other liabilities, which may have a material adverse impact on us. Middle East Dispute On July 30, 2019, we received notice that a local partner of legacy Ensco plc in the Middle East filed a lawsuit in the U.K. against the Company alleging it induced the breach of a non-compete provision in an agreement between the local partner and a subsidiary of the Company. The lawsuit included a claim for an unspecified amount of damages in excess of £100 million and other relief. The Company expects to reach an agreement to settle this matter and to acquire the local partner's interest in the subsidiary for an aggregate amount of $27.5 million . Of this amount, we concluded that $20.3 million was attributable to the settlement of the dispute and was recognized as a loss included in other, net, in our consolidated statement of operations for the year ended December 31, 2019. The remaining amount is attributable to the acquisition of the local partner's interest in the subsidiary and will be recorded to equity in 2020. ARO Funding Obligations Valaris and Saudi Aramco have agreed to take all steps necessary to ensure that ARO purchases at least 20 newbuild jackup rigs ratably over an approximate 10-year period. In January 2020, ARO ordered the first two newbuild jackups for delivery scheduled in 2022. The partners intend for the newbuild jackup rigs to be financed out of available cash from ARO's operations and/or funds available from third-party debt financing. In the event ARO has insufficient cash from operations or is unable to obtain third-party financing, each partner may periodically be required to make additional capital contributions to ARO, up to a maximum aggregate contribution of $1.25 billion from each partner to fund the newbuild program. Each partner's commitment shall be reduced by the actual cost of each newbuild rig, on a proportionate basis. The partners agreed that Saudi Aramco, as a customer, will provide drilling contracts to ARO in connection with the acquisition of the newbuild rigs. The initial contracts for each newbuild rig will be determined using a pricing mechanism that targets a six-year payback period for construction costs on an EBITDA basis. The initial eight-year contracts will be followed by a minimum of another eight years of term, re-priced in three-year intervals based on a market pricing mechanism. Other Matters In addition to the foregoing, we are named defendants or parties in certain other lawsuits, claims or proceedings incidental to our business and are involved from time to time as parties to governmental investigations or proceedings, including matters related to taxation, arising in the ordinary course of business. Although the outcome of such lawsuits or other proceedings cannot be predicted with certainty and the amount of any liability that could arise with respect to such lawsuits or other proceedings cannot be predicted accurately, we do not expect these matters to have a material adverse effect on our financial position, operating results and cash flows. In the ordinary course of business with customers and others, we have entered into letters of credit to guarantee our performance as it relates to our drilling contracts, contract bidding, customs duties, tax appeals and other obligations in various jurisdictions. Letters of credit outstanding as of December 31, 2019 totaled $99.5 million and are issued under facilities provided by various banks and other financial institutions. Obligations under these letters of credit and surety bonds are not normally called, as we typically comply with the underlying performance requirement. As of December 31, 2019 , we had not been required to make collateral deposits with respect to these agreements.

Leases Leases

Leases Leases	12 Months Ended
	Dec. 31, 2019
Leases [Abstract]
Leases	We have operating leases for office space, facilities, equipment, employee housing and certain rig berthing facilities. For all asset classes, except office space, we account for the lease component and the non-lease component as a single lease component. Our leases have remaining lease terms of less than one year to 10 years, some of which include options to extend. Additionally, we sublease certain office space to third parties. During the year ended December 31, 2019 , we recorded lease impairments of $5.6 million related to the impairment of the right-of-use assets associated with an office space and a leased yard facility that were abandoned due to the consolidation of certain corporate offices and leased facilities. The components of lease expense as of December 31, 2019 is as follows (in millions): Long-term operating lease cost $ 29.5 Short-term operating lease cost 12.2 Sublease income (2.4 ) Total operating lease cost $ 39.3 Supplemental balance sheet information related to our operating leases is as follows (in millions, except lease term and discount rate) as of December 31, 2019 : Operating lease right-of-use assets (1) $ 58.1 Current lease liability (1) $ 21.1 Long-term lease liability (1) 51.8 Total operating lease liabilities $ 72.9 Weighted-average remaining lease term (in years) 5.1 Weighted-average discount rate (2) 8.23 % (1) The right-of-use assets include $12.2 million acquired in the Rowan Transaction. The current and long-term lease liabilities include $3.9 million and $10.6 million , respectively, assumed in the Rowan Transaction. (2) Represents our estimated incremental borrowing cost on a secured basis for similar terms as the underlying leases. For the year ended December 31, 2019 , cash paid for amounts included in the measurement of our operating lease liabilities was $29.9 million . We are obligated under leases for certain of our offices and equipment. Rental expense relating to operating leases was $40.1 million and $37.0 million during the years ended December 31, 2018 and 2017 , respectively. Maturities of lease liabilities as of December 31, 2019 were as follows (in millions): 2020 $ 25.4 2021 18.4 2022 12.6 2023 10.7 2024 8.1 Thereafter 17.2 Total lease payments $ 92.4 Less imputed interest 19.5 Total $ 72.9 Future minimum rental payments under non-cancelable operating leases as of December 31, 2018 were as follows (in millions): 2019 $ 32.3 2020 18.7 2021 11.9 2022 9.2 2023 8.9 Thereafter 15.2 Total lease payments $ 96.2

Segment Information

Segment Information	12 Months Ended
	Dec. 31, 2019
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Segment Information	SEGMENT INFORMATION Prior to the Rowan Transaction, our business consisted of three operating segments: (1) Floaters, which included our drillships and semisubmersible rigs, (2) Jackups, and (3) Other, which consisted of management services on rigs owned by third-parties. Floaters and Jackups were also reportable segments. As a result of the Rowan Transaction, we concluded that we would maintain the aforementioned segment structure while adding ARO as a reportable segment for the new combined company. We also concluded that the activities associated with our arrangements with ARO, consisting of our Transition Services Agreement, Rig Lease Agreements and Secondment Agreement, do not constitute reportable segments and are therefore included within Other in the following segment disclosures. Substantially all of the expenses incurred associated with our Transition Services Agreement are included in general and administrative under "Reconciling Items" in the table set forth below. General and administrative expense and depreciation expense incurred by our corporate office are not allocated to our operating segments for purposes of measuring segment operating income (loss) and are included in "Reconciling Items." We measure segment assets as property and equipment. The full operating results included below for ARO (representing only results of ARO from the Transaction Date) are not included within our consolidated results and thus deducted under "Reconciling Items" and replaced with our equity in earnings of ARO. See Note 4 for additional information on ARO and related arrangements. Segment information for each of the years in the three-year period ended December 31, 2019 is presented below (in millions). Year Ended December 31, 2019 Floaters Jackups ARO Other Reconciling Items Consolidated Total Revenues $ 1,014.4 $ 834.6 $ 410.5 $ 204.2 $ (410.5 ) $ 2,053.2 Operating expenses Contract drilling (exclusive of depreciation) 898.6 788.9 280.2 118.5 (280.2 ) 1,806.0 Loss on impairment 88.2 10.2 — — 5.6 104.0 Depreciation 378.6 212.4 40.3 — (21.6 ) 609.7 General and administrative — — 27.1 — 161.8 188.9 Equity in earnings of ARO — — — — (12.6 ) (12.6 ) Operating income (loss) $ (351.0 ) $ (176.9 ) $ 62.9 $ 85.7 $ (288.7 ) $ (668.0 ) Property and equipment, net $ 10,073.1 $ 4,322.7 $ 650.7 $ 701.1 $ (650.7 ) $ 15,096.9 Capital expenditures $ 31.4 $ 184.6 $ 27.5 $ — $ (16.5 ) $ 227.0 Year Ended December 31, 2018 Floaters Jackups ARO Other Reconciling Items Consolidated Total Revenues $ 1,013.5 $ 630.9 $ — $ 61.0 $ — $ 1,705.4 Operating expenses — Contract drilling (exclusive of depreciation) 737.4 526.5 — 55.5 — 1,319.4 Loss on impairment — 40.3 — — — 40.3 Depreciation 311.8 153.3 — — 13.8 478.9 General and administrative — — — — 102.7 102.7 Operating income (loss) $ (35.7 ) $ (89.2 ) $ — $ 5.5 $ (116.5 ) $ (235.9 ) Property and equipment, net $ 9,465.6 $ 3,114.1 $ — $ — $ 36.5 $ 12,616.2 Capital expenditures $ 105.5 $ 317.7 $ — $ — $ 3.5 $ 426.7 Year Ended December 31, 2017 Floaters Jackups ARO Other Reconciling Items Consolidated Total Revenues $ 1,143.5 $ 640.3 $ — $ 59.2 $ — $ 1,843.0 Operating expenses — Contract drilling (exclusive of depreciation) 624.2 512.1 — 53.2 — 1,189.5 Loss on impairment 174.7 8.2 — — — 182.9 Depreciation 297.4 131.5 — — 15.9 444.8 General and administrative — — — — 157.8 157.8 Operating income (loss) $ 47.2 $ (11.5 ) $ — $ 6.0 $ (173.7 ) $ (132.0 ) Property and equipment, net $ 9,650.9 $ 3,177.6 $ — $ — $ 45.2 $ 12,873.7 Capital expenditures $ 470.3 $ 62.1 $ — $ — $ 4.3 $ 536.7 Information about Geographic Areas As of December 31, 2019 , our Floaters segment consisted of 16 drillships, eight dynamically positioned semisubmersible rigs and two moored semisubmersible rigs deployed in various locations. Of the drillships included in our Floaters segment, two ultra-deepwater drillships are under construction in South Korea. Our Jackups segment consisted of 41 jackup rigs which were deployed in various locations and our Other segment consisted of nine jackup rigs that are leased to our 50/50 joint venture with Saudi Aramco. Additionally, we had three rigs classified as held-for-sale. As of December 31, 2019 , the geographic distribution of our and ARO's drilling rigs was as follows: Floaters Jackups Other Total ARO North & South America 10 8 — 18 — Europe & the Mediterranean 7 14 — 21 — Middle East & Africa 4 12 9 25 7 Asia & Pacific Rim 3 7 — 10 — Asia & Pacific Rim (under construction) 2 — — 2 — Held-for-sale 1 2 — 3 — Total 27 43 9 79 7 We provide management services on two rigs owned by third-parties not included in the table above. For purposes of our long-lived asset geographic disclosure, we attribute assets to the geographic location of the drilling rig as of the end of the applicable year. For new construction projects, assets are attributed to the location of future operation if known or to the location of construction if the ultimate location of operation is undetermined. Information by country for those countries that account for more than 10% of our long-lived assets as well as the United Kingdom, our country of domicile, was as follows (in millions): Long-lived Assets 2019 2018 2017 Spain $ 3,012.4 $ 2,306.6 $ 2,004.2 United States 2,943.9 2,270.0 2,764.9 Saudi Arabia 1,257.7 668.6 93.6 United Kingdom 1,204.0 1,185.2 609.4 Nigeria 787.3 1,368.2 583.3 Singapore 22.6 23.9 2,859.3 Other countries 5,869.0 4,793.7 3,959.0 Total $ 15,096.9 $ 12,616.2 $ 12,873.7

Supplemental Financial Informat

Supplemental Financial Information	12 Months Ended
	Dec. 31, 2019
Supplemental Financial Information [Abstract]
Supplemental Balance Sheet Disclosures [Text Block]	. SUPPLEMENTAL FINANCIAL INFORMATION Consolidated Balance Sheet Information Accounts receivable, net, as of December 31, 2019 and 2018 consisted of the following (in millions): 2019 2018 Trade $ 466.4 $ 301.7 Other 60.3 46.4 526.7 348.1 Allowance for doubtful accounts (6.0 ) (3.4 ) $ 520.7 $ 344.7 Other current assets as of December 31, 2019 and 2018 consisted of the following (in millions): 2019 2018 Materials and supplies $ 340.1 $ 268.1 Prepaid taxes 36.2 35.0 Deferred costs 23.3 23.5 Prepaid expenses 13.5 15.2 Other 33.4 19.1 $ 446.5 $ 360.9 Other assets as of December 31, 2019 and 2018 consisted of the following (in millions): 2019 2018 Right-of-use assets $ 58.1 $ — Tax receivables 36.3 8.4 Deferred tax assets 26.6 29.4 Supplemental executive retirement plan assets 26.0 27.2 Intangible assets 11.9 2.5 Deferred costs 7.1 13.5 Other 22.3 16.8 $ 188.3 $ 97.8 Accrued liabilities and other as of December 31, 2019 and 2018 consisted of the following (in millions): 2019 2018 Personnel costs $ 134.4 $ 82.5 Accrued interest 115.2 100.6 Income and other taxes payable 61.2 36.9 Deferred revenue 30.0 56.9 Lease liabilities 21.1 — Other 55.8 41.1 $ 417.7 $ 318.0 Other liabilities as of December 31, 2019 and 2018 consisted of the following (in millions): 2019 2018 Unrecognized tax benefits (inclusive of interest and penalties) $ 323.1 $ 177.0 Pension and other post-retirement benefits 246.7 — Deferred tax liabilities 99.0 70.7 Intangible liabilities 52.1 53.5 Lease liabilities 51.8 — Supplemental executive retirement plan liabilities 26.7 28.1 Personnel costs 24.5 25.1 Deferred revenue 9.7 20.5 Other 33.8 21.1 $ 867.4 $ 396.0 Accumulated other comprehensive income as of December 31, 2019 and 2018 consisted of the following (in millions): 2019 2018 Derivative instruments $ 22.6 $ 12.6 Pension and other post-retirement benefits (21.7 ) — Currency translation adjustment 7.1 7.3 Other (1.8 ) (1.7 ) $ 6.2 $ 18.2 Consolidated Statement of Operations Information Repair and maintenance expense related to continuing operations for each of the years in the three-year period ended December 31, 2019 was as follows (in millions): 2019 2018 2017 Repair and maintenance expense $ 303.7 $ 198.4 $ 188.7 Other, net, for each of the years in the three-year period ended December 31, 2019 consisted of the following (in millions): 2019 2018 2017 Gain on bargain purchase and measurement period adjustments $ 637.0 $ 1.8 $ 140.2 SHI settlement 200.0 — — Gain (loss) on extinguishment of debt 194.1 (19.0 ) (2.6 ) Settlement of legal dispute (20.3 ) — — Currency translation adjustments (7.4 ) (17.2 ) (5.1 ) Other 1.0 (.4 ) 1.9 $ 1,004.4 $ (34.8 ) $ 134.4 Consolidated Statement of Cash Flows Information Net cash provided by (used in) operating activities of continuing operations attributable to the net change in operating assets and liabilities for each of the years in the three-year period ended December 31, 2019 was as follows (in millions): 2019 2018 2017 (Increase) decrease in accounts receivable $ 29.5 $ (6.2 ) $ 83.2 Increase in other assets (32.0 ) (2.8 ) (14.0 ) Increase (Decrease) in liabilities (25.4 ) 2.7 3.2 $ (27.9 ) $ (6.3 ) $ 72.4 During periods in which our business contracts, resulting in significantly lower revenues and expenses as compared to the prior year, we typically generate positive cash flows from the net change in operating assets and liabilities as the impact from the collection of receivables that were accrued during the prior period is generally larger than the impact from the payment of expenses incurred in the prior period. During 2019, we experienced moderate improvements in fleet utilization coupled with the Rowan Transaction that resulted in negative cash flows from changes in operating assets and liabilities. During 2018 , our business contracted at a more moderate pace, resulting in modest negative cash flows from the net change in operating assets and liabilities. During 2017, our business contracted significantly as compared to the respective prior year periods resulting in positive cash generated from the net change in operating assets and liabilities. Cash paid for interest and income taxes for each of the years in the three-year period ended December 31, 2019 was as follows (in millions): 2019 2018 2017 Interest, net of amounts capitalized $ 410.0 $ 232.6 $ 199.8 Income taxes 107.6 58.4 62.8 Capitalized interest totaled $20.9 million , $62.6 million and $72.5 million during the years ended December 31, 2019, 2018 and 2017 , respectively. Capital expenditure accruals totaling $16.3 million , $27.8 million and $243.3 million for the years ended December 31, 2019, 2018 and 2017 , respectively, were excluded from investing activities in our consolidated statements of cash flows. Amortization, net, includes amortization of deferred mobilization revenues and costs, deferred capital upgrade revenues, intangible amortization and other amortization. Other includes amortization of debt discounts and premiums, deferred financing costs, deferred charges for income taxes incurred on intercompany transfers of drilling rigs and other items. Concentration of Risk We are exposed to credit risk relating to our receivables from customers, our cash and cash equivalents, investments 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 investments by focusing on diversification and quality of instruments. Short-term investments consist of a portfolio of time deposits held with several well-capitalized financial institutions, and we monitor the financial condition of those financial institutions. We mitigate our credit risk relating to counterparties of our derivatives through a variety of techniques, including transacting with multiple, high-quality financial institutions, thereby limiting our exposure to individual counterparties and by entering into ISDA Master Agreements, which include provisions for a legally enforceable master netting agreement, with our derivative counterparties. See " Note 8 - Derivative Instruments" for additional information on our derivative activity. 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. Consolidated revenues by customer for the years ended December 31, 2019 , 2018 and 2017 were as follows: 2019 2018 2017 Total (1) 16 % 15 % 22 % BP (2) 9 % 7 % 15 % Saudi Aramco (3) 7 % 11 % 9 % Petrobras (4) 4 % 8 % 11 % Other 64 % 59 % 43 % 100 % 100 % 100 % (1) For the years ended December 31, 2019 , 93% of revenues provided by Total were attributable to the Floaters segment and the remainder was attributable to the Jackup segment. During the years 2018 and 2017 , all Total revenues were attributable to the Floater segment. (2) For the year ended December 31, 2019, 16% , 43% and 41% of BP revenues were attributable to our Floater, Other and Jackup segments, respectively. For the year ended December 31, 2018, 27% , 53% and 20% of BP revenues were attributable to our Floater, Other and Jackup segments, respectively. For the year ended December 31, 2017, 78% of BP revenues were attributable to our Floater segment and the remaining revenues were attributable to our Other segment. (3) For the years ended December 31, 2019, 2018 and 2017 , all Saudi Aramco revenues were attributable to the Jackup segment. (4) For the years ended December 31, 2019, 2018 and 2017 , all Petrobras revenues were attributable to the Floater segment. For purposes of our geographic disclosure, we attribute revenues to the geographic location where such revenues are earned. Consolidated revenues by region, including the United Kingdom, our country of domicile, for the years ended December 31, 2019, 2018 and 2017 were as follows (in millions): 2019 2018 2017 Saudi Arabia (1) $ 313.4 $ 182.2 $ 171.8 U.S. Gulf of Mexico (2) 301.0 214.7 149.8 Angola (3) 284.0 285.7 445.7 United Kingdom (4) 213.1 192.6 164.6 Australia (5) 204.2 283.9 206.7 Brazil (6) 117.8 139.6 196.2 Egypt (7) 40.4 31.2 214.8 Other 579.3 375.5 293.4 $ 2,053.2 $ 1,705.4 $ 1,843.0 (1) For the years ended December 31, 2019 , 65% and 35% of revenues were attributable to our Jackup and Other segments, respectively. For the years ended December 31, 2018 and 2017 , all revenues earned were attributable to our Jackup segment. (2) For the years ended December 31, 2019, 2018 and 2017 , 46% , 30% and 29% of revenues earned in the U.S. Gulf of Mexico, respectively, were attributable to our Floaters segment, 28% , 42% and 31% of revenues were attributable to our Jackup segment, respectively, and the remaining revenues were attributable to our Other segment, respectively. (3) For the years ended December 31, 2019, 2018 and 2017 , 87% , 86% and 88% of revenues earned in Angola, respectively, were attributable to our Floaters segment with the remaining revenues attributable to our Jackup segment. (4) For the years ended December 31, 2019, 2018 and 2017 , all revenues earned in the United Kingdom were attributable to our Jackup segment. (5) For the years ended December 31, 2019, 2018 and 2017 , 90% , 92% and 87% of revenues earned in Australia, respectively, were attributable to our Floaters segment with the remaining revenues attributable to our Jackup segment. (6) For the years ended December 31, 2019, 2018 and 2017 , all revenues earned in Brazil were attributable to our Floaters segment. (7) For the years ended December 31, 2019, 2018 and 2017 , all revenues earned in Egypt were attributable to our Floaters segment.

Guarantee Of Registered Securit

Guarantee Of Registered Securities	12 Months Ended
	Dec. 31, 2019
Guarantees [Abstract]
Guarantee Of Registered Securities	GUARANTEE OF REGISTERED SECURITIES In connection with the Pride acquisition, Valaris and Pride entered into a supplemental indenture to the indenture dated as of July 1, 2004 between Pride and the Bank of New York Mellon, as indenture trustee, providing for, among other matters, the full and unconditional guarantee by Valaris of Pride’s 6.875% senior notes due 2020 and 7.875% senior notes due 2040 , which had an aggregate outstanding principal balance of $422.9 million as of December 31, 2019 . The Valaris guarantee provides for the unconditional and irrevocable guarantee of the prompt payment, when due, of any amount owed to the holders of the notes. Valaris is also a full and unconditional guarantor of the 7.2% Debentures due 2027 issued by Ensco International Incorporated in November 1997, which had an aggregate outstanding principal balance of $112.1 million as of December 31, 2019 . Pride International LLC and Ensco International Incorporated are 100% owned subsidiaries of Valaris. All guarantees are unsecured obligations of Valaris ranking equal in right of payment with all of its existing and future unsecured and unsubordinated indebtedness. The following tables present our condensed consolidating statements of operations for each of the years in the three-year period ended December 31, 2019 ; our condensed consolidating statements of comprehensive income (loss) for each of the years in the three-year period ended December 31, 2019 ; our condensed consolidating balance sheets as of December 31, 2019 and 2018 ; and our condensed consolidating statements of cash flows for each of the years in the three-year period ended December 31, 2019 , in accordance with Rule 3-10 of Regulation S-X. VALARIS PLC AND SUBSIDIARIES Valaris plc ENSCO International Incorporated Pride International LLC Other Non-guarantor Subsidiaries of Valaris Consolidating Adjustments Total OPERATING REVENUES $ 56.7 $ 165.5 $ — $ 2,168.9 $ (337.9 ) $ 2,053.2 OPERATING EXPENSES Contract drilling (exclusive of depreciation) 82.6 147.1 — 1,914.2 (337.9 ) 1,806.0 Loss on impairment — — — 104.0 — 104.0 Depreciation .1 17.3 — 592.3 — 609.7 General and administrative 85.5 .4 — 103.0 — 188.9 168.2 164.8 — 2,713.5 (337.9 ) 2,708.6 EQUITY IN EARNINGS OF ARO — — — (12.6 ) — (12.6 ) OPERATING INCOME (LOSS) (111.5 ) 0.7 — (557.2 ) — (668.0 ) OTHER INCOME (EXPENSE), NET 723.9 (35.7 ) (80.8 ) (20.2 ) 17.0 604.2 INCOME (LOSS) FROM CONTINUING OPERATIONS BEFORE INCOME TAXES 612.4 (35.0 ) (80.8 ) (577.4 ) 17.0 (63.8 ) INCOME TAX EXPENSE — 39.8 — 88.6 — 128.4 EQUITY EARNINGS (LOSSES) IN AFFILIATES, NET OF TAX (810.4 ) 47.8 25.0 — 737.6 — NET LOSS (198.0 ) (27.0 ) (55.8 ) (666.0 ) 754.6 (192.2 ) NET INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS — — — (5.8 ) — (5.8 ) NET LOSS ATTRIBUTABLE TO VALARIS $ (198.0 ) $ (27.0 ) $ (55.8 ) $ (671.8 ) $ 754.6 $ (198.0 ) VALARIS PLC AND SUBSIDIARIES Valaris plc ENSCO International Incorporated Pride International LLC Other Non-guarantor Subsidiaries of Valaris Consolidating Adjustments Total OPERATING REVENUES $ 49.5 $ 155.2 $ — $ 1,802.8 $ (302.1 ) $ 1,705.4 OPERATING EXPENSES Contract drilling (exclusive of depreciation) 51.0 139.5 — 1,431.0 (302.1 ) 1,319.4 Loss on impairment — — — 40.3 — 40.3 Depreciation — 14.2 — 464.7 — 478.9 General and administrative 46.3 .4 — 56.0 — 102.7 OPERATING INCOME (LOSS) (47.8 ) 1.1 — (189.2 ) — (235.9 ) OTHER INCOME (EXPENSE), NET 2.7 (135.2 ) (89.0 ) (109.0 ) 27.5 (303.0 ) LOSS FROM CONTINUING OPERATIONS BEFORE INCOME TAXES (45.1 ) (134.1 ) (89.0 ) (298.2 ) 27.5 (538.9 ) INCOME TAX EXPENSE — 43.3 — 46.3 — 89.6 DISCONTINUED OPERATIONS, NET — — — (8.1 ) — (8.1 ) EQUITY EARNINGS (LOSSES) IN AFFILIATES, NET OF TAX (594.6 ) 121.8 93.3 — 379.5 — NET INCOME (LOSS) (639.7 ) (55.6 ) 4.3 (352.6 ) 407.0 (636.6 ) NET INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS — — — (3.1 ) — (3.1 ) NET INCOME (LOSS) ATTRIBUTABLE TO VALARIS $ (639.7 ) $ (55.6 ) $ 4.3 $ (355.7 ) $ 407.0 $ (639.7 ) VALARIS PLC AND SUBSIDIARIES Valaris plc ENSCO International Incorporated Pride International LLC Other Non-guarantor Subsidiaries of Valaris Consolidating Adjustments Total OPERATING REVENUES $ 52.9 $ 163.3 $ — $ 1,941.2 $ (314.4 ) $ 1,843.0 OPERATING EXPENSES Contract drilling (exclusive of depreciation) 50.0 149.9 — 1,304.0 (314.4 ) 1,189.5 Loss on impairment — — — 182.9 — 182.9 Depreciation — 15.9 — 428.9 — 444.8 General and administrative 45.4 50.8 — 61.6 — 157.8 OPERATING LOSS (42.5 ) (53.3 ) — (36.2 ) — (132.0 ) OTHER INCOME (EXPENSE), NET (6.8 ) (110.5 ) (71.7 ) 110.5 14.5 (64.0 ) INCOME (LOSS) FROM CONTINUING OPERATIONS BEFORE INCOME TAXES (49.3 ) (163.8 ) (71.7 ) 74.3 14.5 (196.0 ) INCOME TAX EXPENSE — 45.0 — 64.2 — 109.2 DISCONTINUED OPERATIONS, NET — — — 1.0 — 1.0 EQUITY EARNINGS (LOSSES) IN AFFILIATES, NET OF TAX (254.4 ) 129.6 84.2 — 40.6 — NET INCOME (LOSS) (303.7 ) (79.2 ) 12.5 11.1 55.1 (304.2 ) NET LOSS ATTRIBUTABLE TO NONCONTROLLING INTERESTS — — — .5 — .5 NET INCOME (LOSS) ATTRIBUTABLE TO VALARIS $ (303.7 ) $ (79.2 ) $ 12.5 $ 11.6 $ 55.1 $ (303.7 ) VALARIS PLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME Year Ended December 31, 2019 (in millions) Valaris plc ENSCO International Incorporated Pride International LLC Other Non-Guarantor Subsidiaries of Valaris Consolidating Adjustments Total NET LOSS $ (198.0 ) $ (27.0 ) $ (55.8 ) $ (666.0 ) $ 754.6 $ (192.2 ) OTHER COMPREHENSIVE INCOME (LOSS), NET Net changes in pension and other postretirement plan assets and benefit obligations recognized in other comprehensive loss, net of income tax benefits of ($5.9 million) — — — (21.7 ) — $ (21.7 ) Net change in fair value of derivatives — 1.6 — — — 1.6 Reclassification of net gains on derivative instruments from other comprehensive loss into net loss — 8.3 — — — 8.3 Other — — — (.2 ) — (.2 ) NET OTHER COMPREHENSIVE INCOME (LOSS) — 9.9 — (21.9 ) — (12.0 ) COMPREHENSIVE LOSS (198.0 ) (17.1 ) (55.8 ) (687.9 ) 754.6 (204.2 ) COMPREHENSIVE INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS — — — (5.8 ) — (5.8 ) COMPREHENSIVE LOSS ATTRIBUTABLE TO VALARIS $ (198.0 ) $ (17.1 ) $ (55.8 ) $ (693.7 ) $ 754.6 $ (210.0 ) VALARIS PLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME Year Ended December 31, 2018 (in millions) ENSCO International Incorporated Pride International LLC Other Non-Guarantor Subsidiaries of Valaris Consolidating Adjustments Total NET INCOME (LOSS) $ (639.7 ) $ (55.6 ) $ 4.3 $ (352.6 ) $ 407.0 $ (636.6 ) OTHER COMPREHENSIVE LOSS, NET Net change in fair value of derivatives — (9.7 ) — — — (9.7 ) Reclassification of net losses on derivative instruments from other comprehensive income into net income — (1.0 ) — — — (1.0 ) Other — — — (.5 ) — (.5 ) NET OTHER COMPREHENSIVE LOSS — (10.7 ) — (.5 ) — (11.2 ) COMPREHENSIVE INCOME (LOSS) (639.7 ) (66.3 ) 4.3 (353.1 ) 407.0 (647.8 ) COMPREHENSIVE INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS — — — (3.1 ) — (3.1 ) COMPREHENSIVE INCOME (LOSS) ATTRIBUTABLE TO VALARIS $ (639.7 ) $ (66.3 ) $ 4.3 $ (356.2 ) $ 407.0 $ (650.9 ) VALARIS PLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME Year Ended December 31, 2017 (in millions) ENSCO International Incorporated Pride International LLC Other Non-Guarantor Subsidiaries of Valaris Consolidating Adjustments Total NET INCOME (LOSS) $ (303.7 ) $ (79.2 ) $ 12.5 $ 11.1 $ 55.1 $ (304.2 ) OTHER COMPREHENSIVE INCOME, NET Net change in fair value of derivatives — 8.5 — — — 8.5 Reclassification of net gains on derivative instruments from other comprehensive income into net loss — .4 — — — .4 Other — — — .7 — .7 NET OTHER COMPREHENSIVE INCOME — 8.9 — .7 — 9.6 COMPREHENSIVE INCOME (LOSS) (303.7 ) (70.3 ) 12.5 11.8 55.1 (294.6 ) COMPREHENSIVE LOSS ATTRIBUTABLE TO NONCONTROLLING INTERESTS — — — .5 — .5 COMPREHENSIVE INCOME (LOSS) ATTRIBUTABLE TO VALARIS $ (303.7 ) $ (70.3 ) $ 12.5 $ 12.3 $ 55.1 $ (294.1 ) VALARIS PLC AND SUBSIDIARIES Valaris plc ENSCO International Incorporated Pride International LLC Other Consolidating Adjustments Total ASSETS CURRENT ASSETS Cash and cash equivalents $ 21.5 $ — $ — $ 75.7 $ — $ 97.2 Short-term investments — — — Accounts receivable, net 0.2 19.7 500.8 — 520.7 Accounts receivable from affiliates 4,031.4 386.0 897.2 (5,314.6 ) — Other .6 11.6 434.3 446.5 Total current assets 4,053.7 417.3 — 1,908.0 (5,314.6 ) 1,064.4 PROPERTY AND EQUIPMENT, AT COST 1.9 108.8 18,283.1 18,393.8 Less accumulated depreciation 1.9 84.7 3,210.3 3,296.9 Property and equipment, net — 24.1 — 15,072.8 — 15,096.9 SHAREHOLDER NOTE FROM ARO — — — 452.9 — 452.9 INVESTMENT IN ARO — — — 128.7 — 128.7 DUE FROM AFFILIATES 73.8 — 38.9 1,775.7 (1,888.4 ) — INVESTMENTS IN AFFILIATES 9,778.5 788.8 1,224.9 — (11,792.2 ) — OTHER ASSETS 7.9 3.8 — 182.6 (6.0 ) 188.3 $ 13,913.9 $ 1,234.0 $ 1,263.8 $ 19,520.7 $ (19,001.2 ) $ 16,931.2 LIABILITIES AND SHAREHOLDERS' EQUITY CURRENT LIABILITIES Accounts payable and accrued liabilities $ 99.2 $ 29.3 $ 12.2 $ 565.2 $ — $ 705.9 Accounts payable to affiliates 818.8 147.8 815.1 3,532.9 (5,314.6 ) — Current maturities of long - term debt — — 124.8 — — 124.8 Total current liabilities 918.0 177.1 952.1 4,098.1 (5,314.6 ) 830.7 DUE TO AFFILIATES 710.3 478.8 586.6 112.7 (1,888.4 ) — LONG-TERM DEBT 2,990.6 111.7 373.3 2,447.9 — 5,923.5 OTHER LIABILITIES (14.6 ) 90.6 — 797.4 (6.0 ) 867.4 VALARIS SHAREHOLDERS' EQUITY (DEFICIT) 9,309.6 375.8 (648.2 ) 12,065.9 (11,792.2 ) 9,310.9 NONCONTROLLING INTERESTS — — — (1.3 ) — (1.3 ) Total equity (deficit) 9,309.6 375.8 (648.2 ) 12,064.6 (11,792.2 ) 9,309.6 $ 13,913.9 $ 1,234.0 $ 1,263.8 $ 19,520.7 $ (19,001.2 ) $ 16,931.2 VALARIS PLC AND SUBSIDIARIES Valaris plc ENSCO International Incorporated Pride International LLC Other Consolidating Adjustments Total ASSETS CURRENT ASSETS Cash and cash equivalents $ 199.8 $ — $ 2.7 $ 72.6 $ — $ 275.1 Short-term investments 329.0 — — — — 329.0 Accounts receivable, net 7.3 25.4 — 312.0 — 344.7 Accounts receivable from affiliates 1,861.2 171.4 — 131.7 (2,164.3 ) — Other .6 6.0 — 354.3 — 360.9 Total current assets 2,397.9 202.8 2.7 870.6 (2,164.3 ) 1,309.7 PROPERTY AND EQUIPMENT, AT COST 1.8 125.2 — 15,390.0 — 15,517.0 Less accumulated depreciation 1.8 91.3 — 2,807.7 — 2,900.8 Property and equipment, net — 33.9 — 12,582.3 — 12,616.2 DUE FROM AFFILIATES 2,413.8 234.5 125.0 2,715.1 (5,488.4 ) — INVESTMENTS IN AFFILIATES 8,522.6 3,713.7 1,199.9 — (13,436.2 ) — OTHER ASSETS 8.1 — — 89.7 — 97.8 $ 13,342.4 $ 4,184.9 $ 1,327.6 $ 16,257.7 $ (21,088.9 ) $ 14,023.7 LIABILITIES AND SHAREHOLDERS' EQUITY CURRENT LIABILITIES Accounts payable and accrued liabilities $ 85.3 $ 32.0 $ 12.7 $ 398.5 $ — $ 528.5 Accounts payable to affiliates 59.7 139.5 38.2 1,926.9 (2,164.3 ) — Total current liabilities 145.0 171.5 50.9 2,325.4 (2,164.3 ) 528.5 DUE TO AFFILIATES 1,432.0 1,226.9 1,366.5 1,463.0 (5,488.4 ) — LONG-TERM DEBT 3,676.5 149.3 502.6 682.0 — 5,010.4 OTHER LIABILITIES 0.1 64.3 — 331.6 — 396.0 VALARIS SHAREHOLDERS' EQUITY (DEFICIT) 8,088.8 2,572.9 (592.4 ) 11,458.3 (13,436.2 ) 8,091.4 NONCONTROLLING INTERESTS — — — (2.6 ) — (2.6 ) Total equity (deficit) 8,088.8 2,572.9 (592.4 ) 11,455.7 (13,436.2 ) 8,088.8 $ 13,342.4 $ 4,184.9 $ 1,327.6 $ 16,257.7 $ (21,088.9 ) $ 14,023.7 VALARIS PLC AND SUBSIDIARIES Valaris plc ENSCO International Incorporated Pride International LLC Other Non-guarantor Subsidiaries of Valaris Consolidating Adjustments Total OPERATING ACTIVITIES Net cash provided by (used in) operating activities of continuing operations $ (181.2 ) $ (57.9 ) $ (111.3 ) $ 73.5 $ — $ (276.9 ) INVESTING ACTIVITIES Acquisition of Rowan, net of cash acquired — — — 931.9 — 931.9 Maturities of short-term investments 474.0 — — — — 474.0 Purchases of short-term investments (145.0 ) — — — — (145.0 ) Additions to property and equipment — — — (227.0 ) — (227.0 ) Net proceeds from disposition of assets — — 17.7 — 17.7 Other (.1 ) — — .1 — — Net cash provided by investing activities of continuing operations 328.9 — — 722.7 — 1,051.6 FINANCING ACTIVITIES Reduction of long-term borrowings (536.6 ) (30.4 ) — (361.1 ) — (928.1 ) Borrowings on credit facility 215.0 — — — — 215.0 Repayments of credit facility borrowings (215.0 ) — — — — (215.0 ) Advances from (to) affiliates 220.6 88.3 108.6 (417.5 ) — — Debt solicitation fees — — — (9.5 ) — (9.5 ) Cash dividends paid (4.5 ) — — — — (4.5 ) Other (5.5 ) — — (4.7 ) — (10.2 ) Net cash provided by (used in) financing activities (326.0 ) 57.9 108.6 (792.8 ) — (952.3 ) Effect of exchange rate changes on cash and cash equivalents — — — (.3 ) — (.3 ) NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS (178.3 ) — (2.7 ) 3.1 — (177.9 ) CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR 199.8 — 2.7 72.6 — 275.1 CASH AND CASH EQUIVALENTS, END OF YEAR $ 21.5 $ — $ — $ 75.7 $ — $ 97.2 VALARIS PLC AND SUBSIDIARIES Valaris plc ENSCO International Incorporated Pride International LLC Other Non-guarantor Subsidiaries of Valaris Consolidating Adjustments Total OPERATING ACTIVITIES Net cash provided by (used in) operating activities of continuing operations $ 18.1 $ (135.1 ) $ (97.6 ) $ 158.9 $ — $ (55.7 ) INVESTING ACTIVITIES Maturities of short-term investments 1,030.0 — — — — 1,030.0 Purchases of short-term investments (919.0 ) — — — — (919.0 ) Additions to property and equipment — — — (426.7 ) — (426.7 ) Net proceeds from disposition of assets — — — 11.0 — 11.0 Purchase of affiliate debt (551.7 ) — — — 551.7 — Sale of affiliate debt 479.0 — — — (479.0 ) — Net cash provided by (used in) investing activities of continuing operations 38.3 — — (415.7 ) 72.7 (304.7 ) FINANCING ACTIVITIES Proceeds from issuance of senior notes 1,000.0 — — — — 1,000.0 Advances from (to) affiliates (845.0 ) 135.1 612.5 97.4 — — Reduction of long-term borrowings (159.9 ) — (537.8 ) (0.8 ) (72.7 ) (771.2 ) Debt issuance costs (17.0 ) — — — — (17.0 ) Cash dividends paid (17.9 ) — — — — (17.9 ) Other (2.0 ) — — (3.7 ) — (5.7 ) Net cash provided by (used in) financing activities (41.8 ) 135.1 74.7 92.9 (72.7 ) 188.2 Net cash provided by discontinued operations — — — 2.5 — 2.5 Effect of exchange rate changes on cash and cash equivalents — — — (.6 ) — (.6 ) NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS 14.6 — (22.9 ) (162.0 ) — (170.3 ) CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR 185.2 — 25.6 234.6 — 445.4 CASH AND CASH EQUIVALENTS, END OF YEAR $ 199.8 $ — $ 2.7 $ 72.6 $ — $ 275.1 VALARIS PLC AND SUBSIDIARIES Valaris plc ENSCO International Incorporated Pride International LLC Other Non-guarantor Subsidiaries of Valaris Consolidating Adjustments Total OPERATING ACTIVITIES Net cash provided by (used in) operating activities of continuing operations $ (18.2 ) $ (117.6 ) $ (100.1 ) $ 495.3 $ — $ 259.4 INVESTING ACTIVITIES Purchases of short-term investments (1,022.9 ) — — (17.1 ) — (1,040.0 ) Additions to property and equipment — — — (536.7 ) — (536.7 ) Maturities of short-term investments 1,748.0 5.5 — 289.0 — 2,042.5 Net proceeds from disposition of assets — — — 2.8 — 2.8 Purchase of affiliate debt (316.3 ) — — — 316.3 — Acquisition of Atwood, net of cash acquired — — — (871.6 ) — (871.6 ) Net cash provided by (used in) investing activities of continuing operations 408.8 5.5 — (1,133.6 ) 316.3 (403.0 ) FINANCING ACTIVITIES Reduction of long-term borrowing (220.7 ) — — — (316.3 ) (537.0 ) Cash dividends paid (13.8 ) — — — — (13.8 ) Debt issuance costs (12.0 ) — — — — (12.0 ) Advances from (to) affiliates (848.9 ) 112.1 105.9 630.9 — — Other (2.6 ) — — (5.1 ) — (7.7 ) Net cash provided by (used in) financing activities (1,098.0 ) 112.1 105.9 625.8 (316.3 ) (570.5 ) Net cash used in discontinued operations — — — (.8 ) — (.8 ) Effect of exchange rate changes on cash and cash equivalents — — — .6 — .6 NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS (707.4 ) — 5.8 (12.7 ) — (714.3 ) CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR 892.6 — 19.8 247.3 — 1,159.7 CASH AND CASH EQUIVALENTS, END OF YEAR $ 185.2 $ — $ 25.6 $ 234.6 $ — $ 445.4

Unaudited Quarterly Financial D

Unaudited Quarterly Financial Data	12 Months Ended
	Dec. 31, 2019
Quarterly Financial Data [Abstract]
Unaudited Quarterly Financial Data	UNAUDITED QUARTERLY FINANCIAL DATA The following tables summarize our unaudited quarterly condensed consolidated income statement data for the years ended December 31, 2019 and 2018 (in millions, except per share amounts): 2019 First Quarter Second Quarter Third Quarter Fourth Quarter Year Operating revenues $ 405.9 $ 583.9 $ 551.3 $ 512.1 $ 2,053.2 Operating expenses Contract drilling (exclusive of depreciation) 332.6 500.3 496.5 476.6 1,806.0 Loss on impairment (1) — 2.5 88.2 13.3 104.0 Depreciation 125.0 157.9 163.0 163.8 609.7 General and administrative 29.6 81.2 36.1 42.0 188.9 Equity in earnings of ARO — 0.6 (3.7 ) (9.5 ) (12.6 ) Operating loss (81.3 ) (157.4 ) (236.2 ) (193.1 ) (668.0 ) Other income (expense), net (75.2 ) 597.3 40.2 41.9 604.2 Income (loss) from continuing operations before income taxes (156.5 ) 439.9 (196.0 ) (151.2 ) (63.8 ) Income tax expense 31.5 32.6 1.5 62.8 128.4 Net income (loss) (188.0 ) 407.3 (197.5 ) (214.0 ) (192.2 ) Net (income) loss attributable to noncontrolling interests (2.4 ) (1.8 ) .4 (2.0 ) (5.8 ) Net income (loss) attributable to Valaris $ (190.4 ) $ 405.5 $ (197.1 ) $ (216.0 ) $ (198.0 ) Income (loss) per share – basic and diluted Continuing operations $ (1.75 ) $ 2.09 $ (1.00 ) $ (1.09 ) $ (1.14 ) Discontinued operations — — — — — $ (1.75 ) $ 2.09 $ (1.00 ) $ (1.09 ) $ (1.14 ) (1) The quarterly periods included losses associated with the impairment of older, less capable, non-core rigs and operating lease impairments. See " Note 6 - Property and Equipment" and " Note 14 - Leases" for additional information. 2018 First Quarter Second Quarter Third Quarter Fourth Quarter Year Operating revenues $ 417.0 $ 458.5 $ 430.9 $ 399.0 $ 1,705.4 Operating expenses Contract drilling (exclusive of depreciation) 325.2 344.3 327.1 322.8 1,319.4 Loss on impairment (1) — — — 40.3 40.3 Depreciation 115.2 120.7 120.6 122.4 478.9 General and administrative 27.9 26.1 25.1 23.6 102.7 Operating loss (51.3 ) (32.6 ) (41.9 ) (110.1 ) (235.9 ) Other expense, net (70.7 ) (84.8 ) (77.7 ) (69.8 ) (303.0 ) Loss from continuing operations before income taxes (122.0 ) (117.4 ) (119.6 ) (179.9 ) (538.9 ) Income tax expense 18.4 24.7 23.3 23.2 89.6 Loss from continuing operations (140.4 ) (142.1 ) (142.9 ) (203.1 ) (628.5 ) Loss from discontinued operations, net (.1 ) (8.0 ) — — (8.1 ) Net loss (140.5 ) (150.1 ) (142.9 ) (203.1 ) (636.6 ) Net (income) loss attributable to noncontrolling interests .4 (.9 ) (2.1 ) (.5 ) (3.1 ) Net loss attributable to Valaris $ (140.1 ) $ (151.0 ) $ (145.0 ) $ (203.6 ) $ (639.7 ) Loss per share – basic and diluted Continuing operations $ (1.29 ) $ (1.31 ) $ (1.34 ) $ (1.88 ) $ (5.82 ) Discontinued operations — (0.08 ) — — (0.08 ) $ (1.29 ) $ (1.39 ) $ (1.34 ) $ (1.88 ) $ (5.90 ) (1) Fourth quarter included an aggregate loss of $40.3 million associated with the impairment of an older, non-core jackup rig. See " Note 6 - Property and Equipment" for additional information.

Description Of The Business A_2

Description Of The Business And Summary Of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Documents Incorporated by Reference [Text Block]	Portions of the Company's Proxy Statement for the 2020 General Meeting of Shareholders are incorporated by reference into Part III of this report.
Business	Business We are a leading provider of offshore contract drilling services to the international oil and gas industry. Exclusive of two rigs under construction and one rigs marked for retirement and classified as held-for-sale, we currently own and operate an offshore drilling rig fleet of 74 rigs, with drilling operations in almost every major offshore market across six continents. Inclusive of our rigs under construction, our fleet includes 16 drillships, eight dynamically positioned semisubmersible rigs, two moored semisubmersible rigs and 50 jackup rigs, nine of which are leased to our 50/50 joint venture with Saudi Aramco. We operate the world's largest fleet amongst competitive rigs, including one of the newest ultra-deepwater fleets in the industry and a leading premium jackup fleet. Our customers include many of the leading national and international oil companies, in addition to many independent operators. We are among the most geographically diverse offshore drilling companies, with current operations spanning 24 countries on six continents. The markets in which we operate include the Gulf of Mexico, Brazil, the Mediterranean, the North Sea, Norway, the Middle East, West Africa, Australia and Southeast Asia. We provide drilling services on a day rate contract basis. Under day rate contracts, we provide an integrated service that includes the provision of a drilling rig and rig crews for which we receive a daily rate that may vary between the full rate and zero rate throughout the duration of the contractual term, depending on the operations of the rig. We also may receive lump-sum fees or similar compensation for the mobilization, demobilization and capital upgrades of our rigs. Our customers bear substantially all of the costs of constructing the well and supporting drilling operations, as well as the economic risk relative to the success of the well.
Rowan Transaction	Rowan Transaction On October 7, 2018 , we entered into a transaction agreement (the "Transaction Agreement") with Rowan Companies Limited (formerly Rowan Companies plc ("Rowan")) and on April 11, 2019 (the "Transaction Date"), we completed our combination with Rowan pursuant to the Transaction Agreement (the "Rowan Transaction") and changed our name to Ensco Rowan plc. On July 30, 2019 , we changed our name to Valaris plc. Rowan's financial results are included in our consolidated results beginning on the Transaction Date. As a result of the Rowan Transaction, Rowan shareholders received 2.750 Valaris Class A ordinary shares for each Rowan Class A ordinary share, representing a value of $43.67 per Rowan share based on a closing price of $15.88 per Valaris share on April 10, 2019 , the last trading day before the Transaction Date. Total consideration delivered in the Rowan Transaction consisted of 88.3 million Valaris shares with an aggregate value of $1.4 billion . All share and per share data included in this report have been retroactively adjusted to reflect the Reverse Stock Split (as defined herein). Prior to the Rowan Transaction, Rowan and Saudi Aramco formed a 50/50 joint venture to own, manage and operate drilling rigs offshore Saudi Arabia ("Saudi Aramco Rowan Offshore Drilling Company" or "ARO"). ARO currently owns a fleet of seven jackup rigs, leases another nine jackup rigs from us and has plans to purchase up to 20 newbuild jackup rigs over an approximate 10 year period. In January 2020, ARO ordered the first two newbuild jackups scheduled for delivery in 2022. The rigs we lease to ARO are done so through bareboat charter agreements whereby substantially all operating costs are incurred by ARO. All nine jackup rigs leased to ARO are under three-year contracts with Saudi Aramco. All seven ARO-owned jackup rigs are under long-term contracts with Saudi Aramco. The Rowan Transaction enhanced the market leadership of the combined company with a fleet of high-specification floaters and jackups and positions us well to meet increasing and evolving customer demand. The increased scale, diversification and financial strength of the combined company provides us advantages to better serve our customers. Exclusive of two older jackup rigs marked for retirement, Rowan’s offshore rig fleet at the Transaction Date consisted of four ultra-deepwater drillships and 19 jackup rigs. Reverse Stock Split Upon closing of the Rowan Transaction, we effected a consolidation (being a reverse stock split under English law) where every four existing Class A ordinary shares, each with a nominal value of $0.10 , were consolidated into one Class A ordinary share, each with a nominal value of $0.40 (the "Reverse Stock Split"). All share and per share data included in this report have been retroactively adjusted to reflect the Reverse Stock Split.
Basis Of Presentation-U.K. Companies Act 2006 Section 435 Statement	Basis of Presentation—U.K. Companies Act 2006 Section 435 Statement The accompanying consolidated financial statements have been prepared in accordance with U.S. GAAP, which the Board of Directors consider to be the most meaningful presentation of our results of operations and financial position. The accompanying consolidated financial statements do not constitute U.K. statutory accounts for the year ended December 31, 2019 and 2018 as required to be prepared under the U.K. Companies Act 2006. The U.K. statutory accounts are prepared in accordance with Financial Reporting Standard 102, the financial reporting standard applicable in the U.K. and Republic of Ireland (“FRS 102”). The auditor has reported on the U.K. statutory accounts for the year ended December 31, 2018; their report was (i) unqualified, (ii) did not include a reference to any matters to which the auditor drew attention by way of emphasis without qualifying their report and (iii) did not contain a statement under section 498 (2) or (3) of the U.K. Companies Act 2006. The U.K. statutory accounts for the year ended December 31, 2019 have yet to be finalized and will be delivered to the U.K. registrar of companies during 2020.
Principles Of Consolidation	Principles of Consolidation The accompanying consolidated financial statements include the accounts of Valaris plc, those of our wholly-owned subsidiaries and entities in which we hold a controlling financial interest. All intercompany accounts and transactions have been eliminated. Investments in operating entities in which we have the ability to exercise significant influence, but where we do not control operating and financial policies are accounted for using the equity method. Significant influence generally exists if we have an ownership interest representing between 20% and 50% of the voting stock of the investee. We account for our interest in ARO using the equity method of accounting and only recognize our portion of equity in earnings in our consolidated financial statements. ARO is a variable interest entity; however, we are not the primary beneficiary and therefore do not consolidate ARO.
Pervasiveness Of Estimates	Pervasiveness of Estimates The preparation of financial statements in conformity with U.S. GAAP requires us to make certain estimates, judgments and assumptions that affect the reported amounts of assets and liabilities, the related revenues and expenses and disclosures of gain and loss contingencies as of the date of the financial statements. Actual results could differ from those estimates.
Foreign Currency Remeasurement And Translation	Foreign Currency Remeasurement and Translation Our functional currency is the U.S. dollar. As is customary in the oil and gas industry, a majority of our revenues and expenses are denominated in U.S. dollars; however, a portion of the revenues earned and expenses incurred by certain of our subsidiaries are denominated in currencies other than the U.S. dollar. These transactions are remeasured in U.S. dollars based on a combination of both current and historical exchange rates. Most transaction gains and losses, including certain gains and losses on our derivative instruments, are included in other, net, in our consolidated statement of operations. Certain gains and losses from the translation of foreign currency balances of our non-U.S. dollar functional currency subsidiaries are included in accumulated other comprehensive income on our consolidated balance sheet. Net foreign currency exchange losses, inclusive of offsetting fair value derivatives, were $7.4 million , $17.2 million and $5.1 million , and were included in other, net, in our consolidated statements of operations for the years ended December 31, 2019, 2018 and 2017 , respectively.
Cash Equivalents And Short-Term Investments	Cash Equivalents and Short-Term Investments Highly liquid investments with maturities of three months or less at the date of purchase are considered cash equivalents. Highly liquid investments with maturities of greater than three months but less than one year at the date of purchase are classified as short-term investments. Short-term investments consisted of time deposits with initial maturities in excess of three months but less than one year and totaled $329.0 million as of December 31, 2018 . There were no short-term investments as of December 31, 2019 . Cash flows from purchases and maturities of short-term investments were classified as investing activities in our consolidated statements of cash flows for the years ended December 31, 2019, 2018 and 2017 . To mitigate our credit risk, our investments in time deposits are diversified across multiple, high-quality financial institutions.
Property And Equipment	Property and Equipment All costs incurred in connection with the acquisition, construction, major enhancement and improvement of assets are capitalized, including allocations of interest incurred during periods that our drilling rigs are under construction or undergoing major enhancements and improvements. Costs incurred to place an asset into service are capitalized, including costs related to the initial mobilization of a newbuild drilling rig. Repair and maintenance costs are charged to contract drilling expense in the period in which they are incurred. Upon the sale or retirement of assets, the related cost and accumulated depreciation are removed from the balance sheet, and the resulting gain or loss is included in contract drilling expense. Our property and equipment is depreciated on a straight-line basis, after allowing for salvage values, over the estimated useful lives of our assets. Drilling rigs and related equipment are depreciated over estimated useful lives ranging from four to 35 years . Buildings and improvements are depreciated over estimated useful lives ranging from seven to 30 years . Other equipment, including computer and communications hardware and software costs, is depreciated over estimated useful lives ranging from three to six years . We evaluate the carrying value of our property and equipment for impairment when events or changes in circumstances indicate that the carrying value of such assets may not be recoverable. For property and equipment used in our operations, recoverability generally is determined by comparing the carrying value of an asset to the expected undiscounted future cash flows of the asset. If the carrying value of an asset is not recoverable, the amount of impairment loss is measured as the difference between the carrying value of the asset and its estimated fair value. Property and equipment held-for-sale is recorded at the lower of net book value or fair value less cost to sell. We recorded pre-tax, non-cash impairment losses related to long-lived assets of $104.0 million , $40.3 million and $182.9 million during 2019 , 2018 and 2017 , respectively. See "Note 6 - Property and Equipment" for additional information on our impairment charges.
Operating Revenues And Expenses	Operating Revenues and Expenses See " Note 2 - Revenue from Contracts with Customers" for information on our accounting policies for revenue recognition and certain operating costs that are deferred and amortized over future periods.
Derivative Instruments	Derivative Instruments We use derivatives to reduce our exposure to various market risks, primarily foreign currency exchange rate risk. See " Note 8 - Derivative Instruments" for additional information on how and why we use derivatives. All derivatives are recorded on our consolidated balance sheet at fair value. Derivatives subject to legally enforceable master netting agreements are not offset on our consolidated balance sheet. Accounting for the gains and losses resulting from changes in the fair value of derivatives depends on the use of the derivative and whether it qualifies for hedge accounting. Derivatives qualify for hedge accounting when they are formally designated as hedges and are effective in reducing the risk exposure that they are designated to hedge. Changes in the fair value of derivatives that are designated as hedges of the variability in expected future cash flows associated with existing recognized assets or liabilities or forecasted transactions ("cash flow hedges") are recorded in accumulated other comprehensive income ("AOCI"). Amounts recorded in AOCI associated with cash flow hedges are subsequently reclassified into contract drilling, depreciation or interest expense as earnings are affected by the underlying hedged forecasted transactions. Gains and losses on a cash flow hedge, or a portion of a cash flow hedge, that no longer qualifies as effective due to an unanticipated change in the forecasted transaction are recognized currently in earnings and included in other, net, in our consolidated statement of operations based on the change in the fair value of the derivative. When a forecasted transaction becomes probable of not occurring, gains and losses on the derivative previously recorded in AOCI are reclassified currently into earnings and included in other, net, in our consolidated statement of operations. We occasionally enter into derivatives that hedge the fair value of recognized assets or liabilities but do not designate such derivatives as hedges or the derivatives otherwise do not qualify for hedge accounting. In these situations, a natural hedging relationship generally exists where changes in the fair value of the derivatives offset changes in the fair value of the underlying hedged items. Changes in the fair value of these derivatives are recognized currently in earnings in other, net, in our consolidated statement of operations. Derivatives with asset fair values are reported in other current assets or other assets, net, on our consolidated balance sheet depending on maturity date. Derivatives with liability fair values are reported in accrued liabilities and other, or other liabilities on our consolidated balance sheet depending on maturity date.
Income Taxes	Income Taxes We conduct operations and earn income in numerous countries. Current income taxes are recognized for the amount of taxes payable or refundable based on the laws and income tax rates in the taxing jurisdictions in which operations are conducted and income is earned. Deferred tax assets and liabilities are recognized for the anticipated future tax effects of temporary differences between the financial statement basis and the tax basis of our assets and liabilities using the enacted tax rates in effect at year-end. A valuation allowance for deferred tax assets is recorded when it is more-likely-than-not that the benefit from the deferred tax asset will not be realized. We do not offset deferred tax assets and deferred tax liabilities attributable to different tax paying jurisdictions. We operate in certain jurisdictions where tax laws relating to the offshore drilling industry are not well developed and change frequently. Furthermore, we may enter into transactions with affiliates or employ other tax planning strategies that generally are subject to complex tax regulations. As a result of the foregoing, the tax liabilities and assets we recognize in our financial statements may differ from the tax positions taken, or expected to be taken, in our tax returns. Our tax positions are evaluated for recognition using a more-likely-than-not threshold, and those tax positions requiring recognition are measured as the largest amount of tax benefit that is greater than 50% likely of being realized upon effective settlement with a taxing authority that has full knowledge of all relevant information. Interest and penalties relating to income taxes are included in current income tax expense in our consolidated statement of operations. Our drilling rigs frequently move from one taxing jurisdiction to another based on where they are contracted to perform drilling services. The movement of drilling rigs among taxing jurisdictions may involve a transfer of drilling rig ownership among our subsidiaries through an intercompany rig sale. The pre-tax profit resulting from an intercompany rig sale is eliminated from our consolidated financial statements, and the carrying value of a rig sold in an intercompany transaction remains at historical net depreciated cost prior to the transaction. Our consolidated financial statements do not reflect the asset disposition transaction of the selling subsidiary or the asset acquisition transaction of the acquiring subsidiary. The income tax effects resulting from intercompany rig sales are recognized in earnings in the period in which the sale occurs. In some instances, we may determine that certain temporary differences will not result in a taxable or deductible amount in future years, as it is more-likely-than-not we will commence operations and depart from a given taxing jurisdiction without such temporary differences being recovered or settled. Under these circumstances, no future tax consequences are expected and no deferred taxes are recognized in connection with such operations. We evaluate these determinations on a periodic basis and, in the event our expectations relative to future tax consequences change, the applicable deferred taxes are recognized or derecognized. We do not provide deferred taxes on the undistributed earnings of certain subsidiaries because our policy and intention is to reinvest such earnings indefinitely. Should we make a distribution from these subsidiaries in the form of dividends or otherwise, we may be subject to additional income taxes. The U.S. Tax Cuts and Jobs Act (“U.S. tax reform”) was enacted on December 22, 2017 and introduced significant changes to U.S. income tax law, including a reduction in the statutory income tax rate from 35% to 21% effective January 1, 2018, a one-time transition tax on deemed repatriation of deferred foreign income, a base erosion anti-abuse tax that effectively imposes a minimum tax on certain payments to non-U.S. affiliates, new and revised rules relating to the current taxation of certain income of foreign subsidiaries and revised rules associated with limitations on the deduction of interest. The U.S. Treasury Department issued guidance and continued finalizing rules associated with U.S. tax reform during 2018 and 2019. See " Note 12 - Income Taxes" for additional information.
Share-Based Compensation	Share-Based Compensation We sponsor share-based compensation plans that provide equity compensation to our key employees, officers and non-employee directors. Our Long-Term Incentive Plan (the “2018 LTIP”) allows our Board of Directors to authorize share grants to be settled in cash or shares. Compensation expense for share awards to be settled in shares is measured at fair value on the date of grant and recognized on a straight-line basis over the requisite service period (usually the vesting period). Compensation expense for share awards to be settled in cash is remeasured each quarter with a cumulative adjustment to compensation cost during the period based on changes in our share price. Any adjustments to the compensation cost recognized in our consolidated statement of operations for awards that are forfeited are recognized in the period in which the forfeitures occur. See " Note 10 - Share Based Compensation" for additional information on our share-based compensation.
Pension and Other Postretirement Plans, Pensions, Policy [Policy Text Block]	Pension and Other Post-retirement benefit plans We measure our actuarially determined obligations and related costs for our defined benefit pension and other post-retirement plans, retiree life and medical supplemental plan benefits, by applying assumptions, the most significant of which include long-term rate of return on plan assets, discount rates and mortality rates. For the long-term rate of return, we develop our assumptions regarding the expected rate of return on plan assets based on historical experience and projected long-term investment returns, and we weight the assumptions based on each plan's asset allocation. For the discount rate, we base our assumptions on a yield curve approach. Actual results may differ from the assumptions included in these calculations. If gains or losses exceed 10% of the greater of the plan assets or plan liabilities, we amortize such gains or losses into income over either the period of expected future service of active participants, or over the expected average remaining lifetime of all participants.
Fair Value Measurements	Fair Value Measurements We measure certain of our assets and liabilities based on a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy assigns the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities ("Level 1") and the lowest priority to unobservable inputs ("Level 3"). Level 2 measurements represent inputs that are observable for similar assets or liabilities, either directly or indirectly, other than quoted prices included within Level 1. See " Note 5 - Fair Value Measurements" for additional information on the fair value measurement of certain of our assets and liabilities.
Noncontrolling Interests	Noncontrolling Interests Third parties hold a noncontrolling ownership interest in certain of our non-U.S. subsidiaries. Noncontrolling interests are classified as equity on our consolidated balance sheet, and net income attributable to noncontrolling interests is presented separately in our consolidated statement of operations. For each of the years in the three-year period ended December 31, 2019 , all income attributable to noncontrolling interest was from continuing operations.
Earnings Per Share	Earnings Per Share We compute basic and diluted earnings per share ("EPS") in accordance with the two-class method. Net loss attributable to Valaris used in our computations of basic and diluted EPS is adjusted to exclude net income allocated to non-vested shares granted to our employees and non-employee directors. Weighted-average shares outstanding used in our computation of diluted EPS is calculated using the treasury stock method and includes the effect of all potentially dilutive stock options and excludes non-vested shares. In each of the years in the three-year period ended December 31, 2019 , our potentially dilutive instruments were not included in the computation of diluted EPS as the effect of including these shares in the calculation would have been anti-dilutive. The following table is a reconciliation of loss from continuing operations attributable to Valaris shares used in our basic and diluted EPS computations for each of the years in the three-year period ended December 31, 2019 (in millions): 2019 2018 2017 Loss from continuing operations attributable to Valaris $ (198.0 ) $ (631.6 ) $ (304.7 ) Income from continuing operations allocated to non-vested share awards (.1 ) (.5 ) (.4 ) Loss from continuing operations attributable to Valaris shares $ (198.1 ) $ (632.1 ) $ (305.1 ) Anti-dilutive share awards totaling 300,000 , 1.5 million and 2.0 million for the years ended December 31, 2019, 2018 and 2017 , respectively, were excluded from the computation of diluted EPS. We have the option to settle our 3.00% exchangeable senior notes due 2024 (the "2024 Convertible Notes") in cash, shares or a combination thereof for the aggregate amount due upon conversion. See " Note 7 - Debt" for additional information on this issuance. Our intent is to settle the principal amount of the 2024 Convertible Notes in cash upon conversion. If the conversion value exceeds the principal amount (i.e., our share price exceeds the exchange price on the date of conversion), we expect to deliver shares equal to the remainder of our conversion obligation in excess of the principal amount. During each respective reporting period that our average share price exceeds the exchange price, an assumed number of shares required to settle the conversion obligation in excess of the principal amount will be included in our denominator for the computation of diluted EPS using the treasury stock method. Our average share price did not exceed the exchange price during the years ended December 31, 2019, 2018 and 2017
New Accounting Pronouncements	New Accounting Pronouncements Recently adopted accounting pronouncements Leases - During 2016, the FASB issued ASU 2016-02, Leases (Topic 842) ("Update 2016-02"), which requires an entity to recognize lease assets and lease liabilities on the balance sheet and to disclose key qualitative and quantitative information about the entity's leasing arrangements. This update is effective for annual and interim periods beginning after December 15, 2018, with early adoption permitted. During our evaluation of Update 2016-02, we concluded that our drilling contracts contain a lease component. In July 2018, the FASB issued Accounting Standard Update 2018-11, Leases (Topic 842), Targeted Improvements , which (1) provided for a new transition method whereby entities could elect to adopt the Update using a prospective with cumulative catch-up approach (the "effective date method") and (2) provided lessors with a practical expedient, by class of underlying asset, to not separate lease and non-lease components and account for the combined component under Topic 606 when the non-lease component is the predominant element of the combined component. The lessor practical expedient is limited to circumstances in which the lease, if accounted for separately, would be classified as an operating lease under Topic 842. We adopted Update 2016-02, effective January 1, 2019, using the effective date method. With respect to our drilling contracts, which contain a lease component, we elected to apply the practical expedient to not separate the lease and non-lease components and account for the combined component under Topic 606. With respect to all of our drilling contracts that existed on the adoption date, we concluded that the criteria to elect the lessor practical expedient had been met. As a result, we will continue to recognize the revenue associated with our drilling contracts under Topic 606. Therefore, we do not expect any change in our revenue recognition patterns or disclosures as a result of our adoption of Topic 842. With respect to leases whereby we are the lessee, we elected several practical expedients afforded under Topic 842. We elected the package of practical expedients permitted under the transition guidance of Topic 842, including the hindsight practical expedient which permits entities to use hindsight in determining the lease term and assessing impairment. We also elected the practical expedient to not separate lease components from non-lease components for all asset classes, with the exception of office space. Furthermore, we also elected the practical expedient that permits entities not to apply the recognition requirements for leases with a term of 12 months or less. Upon adoption of Update 2016-02 on January 1, 2019, we recognized lease liabilities and right-of-use assets of $64.6 million and $53.7 million , respectively. See " Note 14 - Leases" for additional information. Derivatives and Hedging - In August 2017, the Financial Accounting Standards Board (the "FASB") issued ASU 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities ("Update 2017-12"), which makes more hedging strategies eligible for hedge accounting, amends presentation and disclosure requirements and changes how companies assess effectiveness, including the elimination of separate measurement and recognition of ineffectiveness on designated hedging instruments. This update is effective for annual and interim periods beginning after December 15, 2018, with early adoption permitted. We adopted Update 2017-12 effective January 1, 2019. As a result, beginning on the effective date, we no longer separately measure and recognize ineffectiveness on our designated cash flow hedges. Update 2017-02 requires a modified retrospective adoption approach whereby amounts previously recorded to earnings for hedge ineffectiveness on hedging relationships that existed as of the adoption date are recorded as a cumulative effect adjustment to opening retained earnings. As of our adoption date, we had no amounts previously recorded for ineffectiveness for hedging relationships that existed as of our adoption date and therefore no cumulative effect adjustment to retained earnings was recorded. Accounting pronouncements to be adopted Income Taxes - In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes ("Update 2019-12"), which removes certain exceptions for investments, intraperiod allocations and interim tax calculations and adds guidance to reduce complexity in accounting for income taxes. We will be required to adopt the amended guidance in annual and interim periods beginning after December 15, 2020, with early adoption permitted. The various amendments in Update 2019-12 are applied on a retrospective basis, modified retrospective basis and prospective basis, depending on the amendment. We are in the process of evaluating the impact this amendment will have on our consolidated financial statements. Defined Benefit Plans - In August 2018, the FASB issued ASU 2018-14, Compensation – Retirement Benefits – Defined Benefit Plans – General (Subtopic 715-20): Disclosure Framework – Changes to the Disclosure Requirements for Defined Benefit Plans ("Update 2018-14"), which modifies the disclosure requirements for employers that sponsor defined benefit pension or other post-retirement plans. We will be required to adopt the amended guidance in annual and interim reports beginning January 1, 2021, with early adoption permitted. Adoption is required to be applied on a retrospective basis to all periods presented. We will adopt the new standard effective January 1, 2021 and do not expect the adoption of Update 2018-14 to have a material impact on our consolidated financial statements. Credit Losses - In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments ("Update 2016-13"), which requires companies to measure credit losses of financial instruments, including customer accounts receivable, utilizing a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates. Subsequent to the issuance of Update 2016-13, the FASB issued several additional Accounting Standard Updates to clarify implementation guidance, provide narrow-scope improvements and provide additional disclosure guidance. Update 2016-13 is effective for fiscal years beginning after December 15, 2019, with early adoption permitted. We will adopt the new standard effective January 1, 2020 and do not expect the adoption of Update 2016-13 to have a material impact on our consolidated financial statements.

Description Of The Business A_3

Description Of The Business And Summary Of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Reconciliation Of Net Income Attributable To Ensco Shares Used In Basic And Diluted EPS Computations	The following table is a reconciliation of loss from continuing operations attributable to Valaris shares used in our basic and diluted EPS computations for each of the years in the three-year period ended December 31, 2019 (in millions): 2019 2018 2017 Loss from continuing operations attributable to Valaris $ (198.0 ) $ (631.6 ) $ (304.7 ) Income from continuing operations allocated to non-vested share awards (.1 ) (.5 ) (.4 ) Loss from continuing operations attributable to Valaris shares $ (198.1 ) $ (632.1 ) $ (305.1 )

Revenue from Contracts with Cus

Revenue from Contracts with Customers (Tables)	12 Months Ended
	Dec. 31, 2019
Revenue from Contract with Customer [Abstract]
Contract with Customer, Asset and Liability [Table Text Block]	The following table summarizes our contract assets and contract liabilities (in millions): December 31, 2019 December 31, 2018 Current contract assets $ 3.5 $ 4.0 Current contract liabilities (deferred revenue) $ 30.0 $ 56.9 Noncurrent contract liabilities (deferred revenue) $ 9.7 $ 20.5 Changes in contract assets and liabilities during the period are as follows (in millions): Contract Assets Contract Liabilities Balance as of January 1, 2019 $ 4.0 $ 77.4 Contract assets and liabilities acquired in the Rowan Transaction 8.4 5.3 Revenue recognized in advance of right to bill customer 1.3 — Increase due to cash received — 42.9 Decrease due to amortization of deferred revenue that was included in the beginning contract liability balance — (56.3 ) Decrease due to amortization of deferred revenue that was added during the period — (29.6 ) Decrease due to transfer to receivables during the period (10.2 ) — Balance as of December 31, 2019 $ 3.5 $ 39.7
Expected Future Amortization of Contract Liabilities	Expected future amortization of our contract liabilities and deferred costs recorded as of December 31, 2019 is set forth in the table below (in millions): 2020 2021 2022 2023 & Thereafter Total Amortization of contract liabilities $ 30.0 $ 7.8 $ 1.9 $ — $ 39.7 Amortization of deferred costs $ 23.2 $ 5.7 $ 1.2 $ 0.4 $ 30.5

Rowan Transaction (Tables)

Rowan Transaction (Tables)	12 Months Ended
	Dec. 31, 2019
Business Combinations [Abstract]
Schedule of Provisional Amounts for Assets Acquired and Liabilities Assumed	The provisional amounts recorded for assets and liabilities acquired are based on preliminary estimates of their fair values as of the Transaction Date and are as follows (in millions): Amounts Recognized as of Transaction Date Measurement Period Adjustments (1) Estimated Fair Value Assets: Cash and cash equivalents $ 931.9 $ — $ 931.9 Accounts receivable (2) 207.1 (3.6 ) 203.5 Other current assets 101.6 (2.4 ) 99.2 Long-term notes receivable from ARO 454.5 — 454.5 Investment in ARO 138.8 2.5 141.3 Property and equipment 2,989.8 (25.8 ) 2,964.0 Other assets 41.7 1.3 43.0 Liabilities: Accounts payable and accrued liabilities 259.4 13.7 273.1 Current portion of long-term debt 203.2 — 203.2 Long-term debt 1,910.9 — 1,910.9 Other liabilities 376.3 34.1 410.4 Net assets acquired 2,115.6 (75.8 ) 2,039.8 Less: Merger consideration (1,402.8 ) — (1,402.8 ) Bargain purchase gain $ 712.8 $ (75.8 ) $ 637.0 (1) The measurement period adjustments reflect changes in the estimated fair values of certain assets and liabilities, primarily related to long-lived assets, deferred income taxes and uncertain tax positions. The measurement period adjustments were recorded to reflect new information obtained about facts and circumstances existing as of the Transaction Date and did not result from subsequent intervening events. (2) Gross contractual amounts receivable totaled $208.3 million as of the Transaction Date.
Business Acquisition, Pro Forma Information	The pro forma results do not include any potential synergies or non-recurring charges that may result directly from the Rowan Transaction. (unaudited) (in millions, except per share amounts) Year Ended 2019 (1) 2018 (2) Revenues $ 2,240.5 $ 2,530.4 Net loss $ (994.3 ) $ (796.5 ) Earnings per share - basic and diluted $ (3.80 ) $ (4.05 ) (1) Pro forma net loss per share was adjusted to exclude an aggregate $108.1 million of transaction-related and integration costs incurred by Ensco and Rowan during 2019 and the $637.0 million bargain purchase gain. (2) Pro forma net loss per share was adjusted to exclude an aggregate $13.8 million

Equity Method Investment in A_2

Equity Method Investment in ARO (Tables)	12 Months Ended
	Dec. 31, 2019
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments	A reconciliation of those components is presented below (in millions): April 11, 2019 - December 31, 2019 50% interest in ARO net income $ 12.3 Amortization of basis differences (24.9 ) Equity in earnings of ARO $ (12.6 ) Summarized financial information for ARO is as follows (in millions): April 11, 2019 - December 31, 2019 Revenues $ 410.5 Operating expenses Contract drilling (exclusive of depreciation) 280.2 Depreciation 40.3 General and administrative 27.1 Operating income 62.9 Other expense, net 28.6 Provision for income taxes 9.7 Net income $ 24.6 December 31, 2019 Current assets $ 407.2 Non-current assets 874.8 Total assets $ 1,282.0 Current liabilities $ 183.2 Non-current liabilities 1,015.5 Total liabilities $ 1,198.7 The following summarizes the total assets and liabilities as reflected in our consolidated balance sheet as well as our maximum exposure to loss related to ARO (in millions). Our maximum exposure to loss is limited to (1) our equity investment in ARO; (2) the outstanding balance on our shareholder notes receivable; and (3) other receivables for services provided to ARO, partially offset by payables for services received. December 31, 2019 Total assets $ 623.5 Less: total liabilities .7 Maximum exposure to loss $ 622.8
Schedule of Related Party Transactions	Revenues recognized by us related to the Lease Agreements, Transition Services Agreement and Secondment Agreement are as follows (in millions): Year Ended December 31, 2019 Lease revenue $ 58.2 Secondment revenue 49.9 Transition Services revenue 17.3 Total revenue from ARO (1) $ 125.4 (1) All of the revenues presented above are included in our Other segment in our segment disclosures. See Note 15 for additional information.
Schedule of Notes Receivable	The following table summarizes the maturity schedule of our notes receivable from ARO as of December 31, 2019 (in millions): Maturity Date Principal Amount October 2027 $ 275.2 October 2028 177.7 Total $ 452.9

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Schedule Of Financial Assets And Liabilities Measured At Fair Value On A Recurring Basis	The following fair value hierarchy table categorizes information regarding our financial assets and liabilities measured at fair value on a recurring basis as of December 31, 2019 and 2018 (in millions): Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total As of December 31, 2019 Supplemental executive retirement plan assets $ 26.0 $ — $ — $ 26.0 Derivatives, net — 5.4 — 5.4 Total financial assets $ 26.0 $ 5.4 $ — $ 31.4 As of December 31, 2018 Supplemental executive retirement plan assets $ 27.2 $ — $ — $ 27.2 Total financial assets 27.2 — — 27.2 Derivatives, net — (10.7 ) — (10.7 ) Total financial liabilities $ — $ (10.7 ) $ — $ (10.7 )
Schedule Of Carrying Values And Estimated Fair Values Of Debt Instruments	The carrying values and estimated fair values of our debt instruments as of December 31, 2019 and 2018 were as follows (in millions): December 31, 2019 December 31, 2018 Carrying Value Estimated Fair Value Carrying Value Estimated Fair Value 6.875% Senior notes due 2020 $ 124.8 $ 117.3 $ 127.5 $ 121.6 4.70% Senior notes due 2021 113.2 95.5 112.7 101.8 4.875% Senior notes due 2022 (2) 599.2 460.5 — — 3.00% Exchangeable senior notes due 2024 (1) 699.0 607.4 666.8 575.5 4.50% Senior notes due 2024 302.0 167.2 619.8 405.2 4.75% Senior notes due 2024 (2) 276.5 201.4 — — 8.00% Senior notes due 2024 295.7 181.7 337.0 273.7 5.20% Senior notes due 2025 331.7 186.7 664.4 443.9 7.375% Senior notes due 2025 (2) 329.2 218.6 — — 7.75% Senior notes due 2026 987.1 575.1 985.0 725.5 7.20% Debentures due 2027 111.7 70.0 149.3 109.1 7.875% Senior notes due 2040 373.3 153.5 375.0 223.2 5.40% Senior notes due 2042 (2) 262.8 194.4 — — 5.75% Senior notes due 2044 973.3 450.0 972.9 566.3 5.85% Senior notes due 2044 (2) 268.8 194.8 — — Total debt $ 6,048.3 $ 3,874.1 $ 5,010.4 $ 3,545.8 Less: current maturities 124.8 — — — Total long-term debt $ 5,923.5 $ 3,874.1 $ 5,010.4 $ 3,545.8 (1) Our 2024 Convertible Notes were issued with a conversion feature. The 2024 Convertible Notes were separated into their liability and equity components on our consolidated balance sheet. The equity component was initially recorded to additional paid-in capital and as a debt discount that will be amortized to interest expense over the life of the instrument. Excluding the unamortized discount, the carrying value of the 2024 Convertible Notes was $838.3 million and $836.3 million as of December 31, 2019 and 2018 , respectively. See "Note 7 - Debt" for additional information on this issuance. (2)

Property And Equipment (Tables)

Property And Equipment (Tables)	12 Months Ended
	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Schedule Of Property And Equipment	Property and equipment as of December 31, 2019 and 2018 consisted of the following (in millions): 2019 2018 Drilling rigs and equipment $ 17,714.0 $ 14,542.5 Work-in-progress 473.6 779.2 Other 206.2 195.3 $ 18,393.8 $ 15,517.0

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
Schedule Of Long-Term Debt Instruments	The carrying value of our long-term debt as of December 31, 2019 and 2018 consisted of the following (in millions): 2019 2018 6.875% Senior notes due 2020 $ 124.8 $ 127.5 4.70% Senior notes due 2021 113.2 112.7 4.875% Senior notes due 2022 (3) 599.2 — 3.00% Exchangeable senior notes due 2024 (2) 699.0 666.8 4.50% Senior notes due 2024 (1) 302.0 619.8 4.75% Senior notes due 2024 (3) 276.5 — 8.00% Senior notes due 2024 (1) 295.7 337.0 5.20% Senior notes due 2025 (1) 331.7 664.4 7.375% Senior notes due 2025 (3) 329.2 — 7.75% Senior notes due 2026 987.1 985.0 7.20% Debentures due 2027 (1) 111.7 149.3 7.875% Senior notes due 2040 373.3 375.0 5.40% Senior notes due 2042 (3) 262.8 — 5.75% Senior notes due 2044 973.3 972.9 5.85% Senior notes due 2044 (3) 268.8 — Total debt $ 6,048.3 $ 5,010.4 Less: current maturities 124.8 — Total long-term debt $ 5,923.5 $ 5,010.4 (1) The decline in the carrying value of our 4.50% and 8.00% senior notes due 2024, 5.20% senior notes due 2025 and 7.20% debentures due 2027 resulted from repurchases made pursuant to the tender offer discussed below. (2) Our 2024 Convertible Notes were issued with a conversion feature. The 2024 Convertible Notes were separated into their liability and equity components on our consolidated balance sheet. The equity component was initially recorded to additional paid-in capital and as a debt discount that will be amortized to interest expense over the life of the instrument. Excluding the unamortized discount, the carrying value of the 2024 Convertible Notes was $838.3 million and $836.3 million as of December 31, 2019 and 2018 , respectively. (3) These senior notes were acquired in the Rowan Transaction.
Convertible Debt	As of December 31, 2019 and 2018 , the 2024 Convertible Notes consist of the following (in millions): Liability component: 2019 2018 Principal $ 849.5 $ 849.5 Less: Unamortized debt discount and issuance costs (150.5 ) (182.7 ) Net carrying amount 699.0 666.8 Equity component, net $ 220.0 $ 220.0
Schedule of Extinguishment of Debt	The exchange offers resulted in the tender of $649.5 million aggregate principal amount of our outstanding notes that were settled and exchanged as follows (in millions): Aggregate Principal Amount Repurchased 8% Senior Notes Due 2024 Consideration Cash Total Consideration 8.50% Senior notes due 2019 $ 145.8 $ 81.6 $ 81.7 $ 163.3 6.875% Senior notes due 2020 129.8 69.3 69.4 138.7 4.70% Senior notes due 2021 373.9 181.1 181.4 362.5 $ 649.5 $ 332.0 $ 332.5 $ 664.5 Our tender offers and open market repurchases during the three-year period ended December 31, 2019 were as follows (in millions): Aggregate Principal Amount Repurchased Aggregate Repurchase Price (1) Year Ended December 31, 2019 4.50% Senior notes due 2024 $ 320.0 $ 240.0 4.75% Senior notes due 2024 79.5 61.2 8.00% Senior notes due 2024 39.7 33.8 5.20% Senior notes due 2025 335.5 250.0 7.375% Senior notes due 2025 139.2 109.2 7.20% Senior notes due 2027 37.9 29.9 $ 951.8 $ 724.1 Year Ended December 31, 2018 8.50% Senior notes due 2019 $ 237.6 $ 256.8 6.875% Senior notes due 2020 328.0 354.7 4.70% Senior notes due 2021 156.2 159.7 $ 721.8 $ 771.2 Year Ended December 31, 2017 8.50% Senior notes due 2019 $ 54.6 $ 60.1 6.875% Senior notes due 2020 100.1 105.1 4.70% Senior notes due 2021 39.4 39.3 $ 194.1 $ 204.5 (1) Excludes accrued interest paid to holders of the repurchased senior notes.
Aggregate Maturities Of Long-Term Debt	The descriptions of our senior notes above reflect the original principal amounts issued, which have subsequently changed as a result of our tenders, repurchases, exchanges, redemptions and new debt issuances such that the maturities of our debt were as follows (in millions): Senior Notes Original Principal 2016 Tenders, Repurchases and Equity Exchange 2017 Exchange Offers and Repurchases 2018 Tender Offers, Redemption and Debt Issuance 2019 Tender Offers, Redemption and Debt Issuance Remaining Principal 6.875% due 2020 $ 900.0 $ (219.2 ) $ (229.9 ) $ (328.0 ) $ — $ 122.9 4.70% due 2021 1,500.0 (817.0 ) (413.3 ) (156.2 ) — 113.5 4.875% due 2022 (1) — — — — 620.8 620.8 3.00% Exchangeable senior notes due 2024 849.5 — — — — 849.5 4.50% due 2024 625.0 (1.7 ) — — (320.0 ) 303.3 4.75% due 2024 (1) — — — — 318.6 318.6 8.00% due 2024 — — 332.0 — (39.7 ) 292.3 5.20% due 2025 700.0 (30.7 ) — — (335.5 ) 333.8 7.375% due 2025 (1) — — — — 360.8 360.8 7.75% due 2026 — — — 1,000.0 — 1,000.0 7.20% due 2027 150.0 — — — (37.9 ) 112.1 7.875% due 2040 300.0 — — — — 300.0 5.40% due 2042 (1) — — — — 400.0 400.0 5.75% due 2044 1,025.0 (24.5 ) — — — 1,000.5 5.85% due 2044 (1) — — — — 400.0 400.0 Total $ 6,049.5 $ (1,093.1 ) $ (311.2 ) $ 515.8 $ 1,367.1 $ 6,528.1 (1) These senior notes were acquired in the Rowan Transaction.

Derivative Instruments (Tables)

Derivative Instruments (Tables)	12 Months Ended
	Dec. 31, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule Of Derivatives At Fair Value	Derivatives recorded at fair value on our consolidated balance sheets as of December 31, 2019 and 2018 consisted of the following (in millions): Derivative Assets Derivative Liabilities 2019 2018 2019 2018 Derivatives Designated as Hedging Instruments Foreign currency forward contracts - current (1) $ 4.2 $ .2 $ .7 $ 8.3 Foreign currency forward contracts - non-current (2) .8 — — .4 5.0 .2 .7 8.7 Derivatives not Designated as Hedging Instruments Foreign currency forward contracts - current (1) 1.3 .4 .2 2.6 Total $ 6.3 $ .6 $ .9 $ 11.3 (1) Derivative assets and liabilities that have maturity dates equal to or less than 12 months from the respective balance sheet dates were included in other current assets and accrued liabilities and other, respectively, on our consolidated balance sheets. (2) Derivative assets and liabilities that have maturity dates greater than 12 months from the respective balance sheet dates were included in other assets and other liabilities, respectively, on our consolidated balance sheets.
Gains And Losses On Derivatives Designated As Cash Flow Hedges	Gains and losses, net of tax, on derivatives designated as cash flow hedges included in our consolidated statements of operations and comprehensive loss for each of the years in the three-year period ended December 31, 2019 were as follows (in millions): Gain (Loss) Recognized in Other Comprehensive Income ("OCI") on Derivatives (Effective Portion) (Gain) Loss Reclassified from AOCI into Income (Effective Portion) (1) Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion and Amount Excluded from Effectiveness Testing) (2) 2019 2018 2017 2019 2018 2017 2019 2018 2017 Interest rate lock contracts (3) $ — $ — $ — $ 1.9 $ .2 $ .2 $ — $ — $ — Foreign currency forward contracts (4) 1.6 (9.7 ) 8.5 6.4 (1.2 ) .2 — (1.9 ) (.7 ) Total $ 1.6 $ (9.7 ) $ 8.5 $ 8.3 $ (1.0 ) $ .4 $ — $ (1.9 ) $ (.7 ) (1) Changes in the fair value of cash flow hedges are recorded in AOCI. Amounts recorded in AOCI associated with cash flow hedges are subsequently reclassified into contract drilling, depreciation or interest expense as earnings are affected by the underlying hedged forecasted transaction. (2) Gains and losses recognized in income for amounts excluded from effectiveness testing were included in other, net, in our consolidated statements of operations. As a result of our adoption of Update 2017-12 on January 1, 2019, ineffectiveness is no longer separately measured and recognized. (3) Losses on interest rate lock derivatives reclassified from AOCI into income were included in interest expense, net, in our consolidated statements of operations. (4) During the year ended December 31, 2019 , $7.3 million of losses were reclassified from AOCI into contract drilling expense and $0.9 million of gains were reclassified from AOCI into depreciation expense in our consolidated statement of operations. During the year ended December 31, 2018 , $400,000 of gains were reclassified from AOCI into contract drilling expense and $800,000 of gains were reclassified from AOCI into depreciation expense in our consolidated statement of operations. During the year ended December 31, 2017 , $1.1 million of losses were reclassified from AOCI into contract drilling expense and $900,000 of gains were reclassified from AOCI into depreciation expense in our consolidated statement of operations.
Schedule Of Estimated Amount Of Net Gains Associated With Derivatives	As of December 31, 2019 , the estimated amount of net gains associated with derivatives, net of tax, that will be reclassified to earnings during the next 12 months was as follows (in millions): Net unrealized losses to be reclassified to contract drilling expense $ 3.4 Net realized gains to be reclassified to depreciation expense .8 Net losses to be reclassified to earnings $ 4.2

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2019
Stockholders' Equity Note [Abstract]
Schedule Of Activity In Our Various Shareholders' Equity	Activity in our various shareholders' equity accounts for each of the years in the three-year period ended December 31, 2019 was as follows (in millions): Shares Par Value Additional Paid-in Capital Retained Earnings AOCI Treasury Shares Non-controlling Interest BALANCE, December 31, 2016 77.6 $ 31.1 $ 6,402.2 $ 1,864.1 $ 19.0 $ (65.8 ) $ 4.4 Net loss — — — (303.7 ) — — (.5 ) Dividends paid ($0.16 per share) — — — (13.6 ) — — — Cumulative-effect reduction from adoption of ASU 2016-16 (14.1 ) Distributions to noncontrolling interests — — — — — — (6.0 ) Equity issuance in connection with Atwood Merger 33.1 13.2 757.5 — — — — Shares issued under share-based compensation plans, net 1.1 .5 (.4 ) — — (1.3 ) — Repurchase of shares — — — — — (1.9 ) — Share-based compensation cost — — 35.7 — — — — Net other comprehensive income — — — — 9.6 — — BALANCE, December 31, 2017 111.8 44.8 7,195.0 1,532.7 28.6 (69.0 ) (2.1 ) Net loss — — — (639.7 ) — — 3.1 Dividends paid ($0.16 per share) — — — (18.0 ) — — — Cumulative-effect reduction from adoption of ASU 2018-02 — — — (.8 ) .8 — — Shares issued under share-based compensation plans, net 3.4 1.4 (.6 ) — — (1.3 ) — Distributions to noncontrolling interests — — — — — — (3.6 ) Repurchase of shares — — — — — (1.9 ) — Share-based compensation cost — — 30.6 — — — — Net other comprehensive income — — — — (11.2 ) — — BALANCE, December 31, 2018 115.2 46.2 7,225.0 874.2 18.2 (72.2 ) (2.6 ) Net loss — — — (198.0 ) — — 5.8 Dividends paid ($0.04 per share) — — — (4.5 ) — — — Equity issuance in connection with the Rowan Transaction 88.0 35.2 1,367.5 — — .1 — Shares issued under share-based compensation plans, net 2.7 1.1 (1.3 ) — — (.7 ) — Repurchase of shares — — — — — (4.5 ) — Share-based compensation cost — — 37.2 — — — — Equity issuance cost — — (.6 ) — — — — Net changes in pension and other postretirement benefits — — — — (21.7 ) — — Distributions to noncontrolling interests — — — — — — (4.5 ) Net other comprehensive income — — — — 9.7 — — BALANCE, December 31, 2019 205.9 $ 82.5 $ 8,627.8 $ 671.7 $ 6.2 $ (77.3 ) $ (1.3 )

Benefit Plans (Tables)

Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2019
Share-based Payment Arrangement [Abstract]
Summary Of Non-Vested Share Award Related Compensation Expense Recognized	The following table summarizes share award and cash-settled award compensation expense recognized during each of the years in the three-year period ended December 31, 2019 (in millions): 2019 2018 2017 Contract drilling $ 22.1 $ 18.9 $ 18.3 General and administrative 17.4 14.5 14.5 39.5 33.4 32.8 Tax benefit (2.5 ) (2.8 ) (4.8 ) Total $ 37.0 $ 30.6 $ 28.0
Summary Of Value Of Non-Vested Share Awards Granted And Vested	The following table summarizes the value of share awards and cash-settled awards granted and vested during each of the years in the three-year period ended December 31, 2019 : Share Awards Cash-Settled Awards 2019 2018 2017 2019 2018 2017 Weighted-average grant-date fair value of share awards granted (per share) $ 11.50 $ 24.62 $ 31.48 $ — $ 21.35 $ 25.08 Total fair value of share awards vested during the period (in millions) $ 17.7 $ 7.5 $ 8.2 $ 3.5 $ 9.9 $ 3.9
Summary Of Non-Vested Share Award Activity	The following table summarizes share awards and cash-settled awards activity for the year ended December 31, 2019 (shares in thousands): Share Awards Cash-settled Awards Awards Weighted-Average Grant-Date Fair Value Awards Weighted-Average Grant-Date Fair Value Share awards and cash-settled awards as of December 31, 2018 2,017 $ 31.36 1,279 $ 29.20 Granted 4,460 11.50 — — Rowan share awards assumed 2,329 15.88 — — Vested (1,519 ) 10.53 (453 ) 7.97 Forfeited (854 ) 8.87 (129 ) 11.58 Share awards and cash-settled awards as of December 31, 2019 6,433 $ 19.89 697 $ 46.28

Pension and Other Post-retire_2

Pension and Other Post-retirement Benefits (Tables)	12 Months Ended
	Dec. 31, 2019
Retirement Benefits [Abstract]
Schedule of Changes in Benefit Obligations and Plan Assets	The following table presents the changes in benefit obligations and plan assets for the year ended December 31, 2019 and the funded status and weighted-average assumptions used to determine the benefit obligation at year end (dollars in millions): 2019 Pension Benefits Other Benefits Total Projected benefit obligation: Balance, April 11 $ 800.1 $ 15.9 $ 816.0 Interest cost 21.3 0.4 21.7 Service cost 1.5 — 1.5 Actuarial loss 43.8 0.2 44.0 Benefits paid (34.1 ) (0.4 ) (34.5 ) Foreign currency adjustments (0.2 ) — (0.2 ) Balance, December 31 $ 832.4 $ 16.1 $ 848.5 Plan assets Fair value, April 11 $ 576.8 $ — $ 576.8 Actual return 43.6 — 43.6 Employer contributions 12.8 — 12.8 Benefits paid (34.1 ) — (34.1 ) Foreign currency adjustments (0.2 ) — (0.2 ) Fair value, December 31 $ 598.9 — $ 598.9 Net benefit liabilities $ 233.5 $ 16.1 $ 249.6 Amounts recognized in consolidated balance sheet: Accrued liabilities $ (1.4 ) $ (1.5 ) $ (2.9 ) Other liabilities (long-term) (232.1 ) (14.6 ) (246.7 ) Net benefit liabilities $ (233.5 ) $ (16.1 ) $ (249.6 ) Accumulated contributions in excess of (less than) net periodic benefit cost $ (206.2 ) $ (15.9 ) $ (222.1 ) Amounts not yet reflected in net periodic benefit cost: Actuarial loss $ (27.3 ) $ (0.2 ) $ (27.5 ) Total accumulated other comprehensive loss (27.3 ) (0.2 ) (27.5 ) Net benefit liabilities $ (233.5 ) $ (16.1 ) $ (249.6 ) Weighted-average assumptions: Discount rate 3.16 % 3.06 % Rate of compensation increase — % — %
Schedule of Accumulated and Projected Benefit Obligations	The accumulated benefit obligations, which are presented below for all plans in the aggregate at December 31, 2019 , are based on services rendered to date, but exclude the effect of future salary increases (in millions): 2019 Accumulated benefit obligation $ 844.3
Schedule of Net Periodic Pension Costs and Weighted Average Assumptions	The components of net periodic pension cost and the weighted-average assumptions used to determine net periodic pension cost were as follows (dollars in millions): April 11, 2019 - December 31, 2019 Service cost (1) $ 1.5 Interest cost (2) 21.3 Expected return on plan assets (2) (27.1 ) Net periodic pension cost (benefit) $ (4.3 ) Discount rate 3.82 % (1) Included in contract drilling and general and administrative expense in our consolidated statements of operations. (2) Included in other, net, in our consolidated statements of operations.
Schedule of Allocation of Plan Assets	Target allocations among asset categories and the fair value of each category of plan assets as of December 31, 2019 , classified by level within the US GAAP fair value hierarchy are presented below. The plans will reallocate assets in accordance with the allocation targets, after giving consideration to the expected level of cash required to pay current benefits and plan expenses (dollars in millions): Target range Total Quoted prices in active markets for identical assets (Level 1) Significant observable inputs (Level 2) Significant unobservable inputs (Level 3) December 31, 2019 Equities: 53% to 69% U.S. large cap 22% to 28% $ 148.9 $ — $ 148.9 $ — U.S. small cap 4% to 10% 41.1 — 41.1 — International all cap 21% to 29% 152.4 — 152.4 — International small cap 2% to 8% 34.7 — 34.7 — Real estate equities 0% to 13% 54.9 — 54.9 — Fixed income: 25% to 35% Cash and equivalents 0% to 10% 6.5 6.5 — — Aggregate 9% to 19% 76.7 — 76.7 — Core plus 9% to 19% 77.6 77.6 — — Group annuity contracts 6.1 — 6.1 — Total $ 598.9 $ 84.1 $ 514.8 $ —
Schedule of Expected Benefit Payments	Estimated future annual benefit payments from plan assets are presented below. Such amounts are based on existing benefit formulas and include the effect of future service (in millions): Pension Benefits Other Post-Retirement Benefits Year ended December 31, 2020 $ 45.0 $ 1.5 2021 45.0 1.4 2022 44.6 1.3 2023 44.2 1.3 2024 43.9 1.3 2025 through 2029 213.6 5.3

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2019
Components of Income Tax Expense (Benefit), Continuing Operations [Abstract]
Summary Of Components Of Provision For Income Taxes From Continuing Operations	The following table summarizes components of our provision for income taxes from continuing operations for each of the years in the three-year period ended December 31, 2019 (in millions): 2019 2018 2017 Current income tax expense (benefit): U.S. $ 31.3 $ (19.9 ) $ (2.2 ) Non-U.S. 73.2 52.9 56.4 104.5 33.0 54.2 Deferred income tax expense: U.S. 19.7 52.9 36.0 Non-U.S. 4.2 3.7 19.0 23.9 56.6 55.0 Total income tax expense $ 128.4 $ 89.6 $ 109.2
Summary Of Significant Components Of Deferred Income Tax Assets (Liabilities)	The following table summarizes significant components of deferred income tax assets and liabilities as of December 31, 2019 and 2018 (in millions): 2019 2018 Deferred tax assets : Net operating loss carryforwards $ 1,546.7 $ 148.4 Net capital loss carryforwards 998.0 — Foreign tax credits 142.9 123.6 Interest limitation carryforwards 41.5 40.2 Premiums on long-term debt — 23.8 Employee benefits, including share-based compensation 73.9 15.4 Deferred revenue 0.1 10.3 Other 11.6 14.5 Total deferred tax assets 2,814.7 376.2 Valuation allowance (2,588.7 ) (316.0 ) Net deferred tax assets 226.0 60.2 Deferred tax liabilities : Property and equipment (156.0 ) (54.5 ) Net discounts on long-term debt (49.5 ) — Deferred U.S. tax on foreign income (36.7 ) (31.5 ) Other (23.7 ) (9.0 ) Total deferred tax liabilities (265.9 ) (95.0 ) Net deferred tax asset (liability) $ (39.9 ) $ (34.8 )
Summary Of Effective Income Tax Rate On Continuing Operations	Our consolidated effective income tax rate on continuing operations for each of the years in the three-year period ended December 31, 2019 , differs from the U.K. statutory income tax rate as follows: 2019 2018 2017 U.K. statutory income tax rate 19.0 % 19.0 % 19.2 % Non-U.K. taxes (280.9 ) (18.0 ) (40.4 ) Bargain purchase gain 189.7 (.2 ) 13.8 Valuation allowance (145.1 ) (16.9 ) (18.0 ) Debt repurchases 48.7 (1.6 ) (2.8 ) Asset impairments (31.0 ) (1.4 ) (17.1 ) U.S. tax reform (21.6 ) 2.2 (8.4 ) Restructuring transaction 7.9 1.7 — Other 12.0 (1.4 ) (2.0 ) Effective income tax rate (201.3 )% (16.6 )% (55.7 )%
Summary Of Reconciliation Of The Beginning And Ending Amount Of Unrecognized Tax Benefits	A reconciliation of the beginning and ending amount of unrecognized tax benefits for the years ended December 31, 2019 and 2018 is as follows (in millions): 2019 2018 Balance, beginning of year $ 143.0 $ 147.6 Increases in unrecognized tax benefits as a result of the Rowan Transaction 149.9 — Increases in unrecognized tax benefits as a result of tax positions taken during the current year 17.8 6.5 Impact of foreign currency exchange rates (.3 ) (5.0 ) Lapse of applicable statutes of limitations (4.4 ) (4.5 ) Increase in unrecognized tax benefits as a result of tax positions taken during prior years 1.1 2.5 Decreases in unrecognized tax benefits as a result (2.4 ) (3.8 ) Settlements with taxing authorities (8.0 ) (.3 ) Balance, end of year $ 296.7 $ 143.0

Commitments And Contingencies (

Commitments And Contingencies (Tables)	12 Months Ended
	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Capital Commitments	The following table summarizes the estimated timing of our remaining contractual payments of our rigs under construction as of December 31, 2019 for our rigs under construction and (in millions): 2020 2021 2022 Thereafter Total (1) VALARIS DS-13 (2) $ — $ 83.9 $ — $ — $ 83.9 VALARIS DS-14 (2) — — 165.0 — 165.0 $ — $ 83.9 $ 165.0 $ — $ 248.9 (1) Total commitments are based on fixed-price shipyard construction contracts, exclusive of costs associated with project management, commissioning and systems integration testing. Total commitments also exclude holding costs and interest. Based on our current projections, excluding integration-related capital expenditures, we expect capital expenditures during 2020 to approximate $ 160 million for newbuild construction, rig enhancement projects and minor upgrades and improvements. Approximately $30 million of our projected capital expenditures is reimbursable by our customers. Depending on market conditions and opportunities, we may reduce our planned expenditures or make additional capital expenditures to upgrade rigs for customer requirements or acquire additional rigs. (2) During the third quarter of 2019, we entered into amendments to our construction agreements with the shipyard for VALARIS DS-13 and VALARIS DS-14 to provide for, among other things, two-year extensions of the delivery date of each rig in exchange for payment of all accrued holding costs through March 31, 2019, totaling approximately $23 million . The new delivery dates for the VALARIS DS-13 and VALARIS DS-14 are September 30, 2021 and June 30, 2022, respectively. We can elect to request earlier delivery in certain circumstances. The interest rate on the final milestone payments increased from 5% to 7% per annum from October 1, 2019, for the VALARIS DS-13, and from July 1, 2020, for the VALARIS DS-14, until the actual delivery dates. The final milestone payments and interest are due at the new delivery dates (or, if accelerated, the actual delivery dates) and are estimated to be approximately $313.3 million in aggregate for both rigs, inclusive of interest, assuming we take delivery on the new delivery dates. In lieu of making the final milestone payments, we have the option to take delivery of the rigs and issue a promissory note for each rig to the shipyard owner for the amount due. If we issue the promissory note to the shipyard owner, we would also be required to provide a guarantee from Valaris plc. Upon delivery, the remaining milestone payments and accrued interest thereon may be financed through a promissory note with the shipyard for each rig. The promissory notes will bear interest at a rate of 9% per annum with a maturity date of December 30, 2022 and will be secured by a mortgage on each respective rig. The remaining milestone payments for VALARIS DS-13 and VALARIS DS-14 are included in the table above in the period in which we expect to take delivery of the rig. However, we may elect to execute the promissory notes and defer payment until December 2022.

Leases Leases (Tables)

Leases Leases (Tables)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Leases [Abstract]
Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block]		Future minimum rental payments under non-cancelable operating leases as of December 31, 2018 were as follows (in millions): 2019 $ 32.3 2020 18.7 2021 11.9 2022 9.2 2023 8.9 Thereafter 15.2 Total lease payments $ 96.2
Components of Lease Expense	The components of lease expense as of December 31, 2019 is as follows (in millions): Long-term operating lease cost $ 29.5 Short-term operating lease cost 12.2 Sublease income (2.4 ) Total operating lease cost $ 39.3
Supplemental Balance Sheet Information	Supplemental balance sheet information related to our operating leases is as follows (in millions, except lease term and discount rate) as of December 31, 2019 : Operating lease right-of-use assets (1) $ 58.1 Current lease liability (1) $ 21.1 Long-term lease liability (1) 51.8 Total operating lease liabilities $ 72.9 Weighted-average remaining lease term (in years) 5.1 Weighted-average discount rate (2) 8.23 % (1) The right-of-use assets include $12.2 million acquired in the Rowan Transaction. The current and long-term lease liabilities include $3.9 million and $10.6 million , respectively, assumed in the Rowan Transaction. (2) Represents our estimated incremental borrowing cost on a secured basis for similar terms as the underlying leases.
Maturities of Lease Liabilities	Maturities of lease liabilities as of December 31, 2019 were as follows (in millions): 2020 $ 25.4 2021 18.4 2022 12.6 2023 10.7 2024 8.1 Thereafter 17.2 Total lease payments $ 92.4 Less imputed interest 19.5 Total $ 72.9

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2019
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Schedule Of Segment Reporting Information	Year Ended December 31, 2019 Floaters Jackups ARO Other Reconciling Items Consolidated Total Revenues $ 1,014.4 $ 834.6 $ 410.5 $ 204.2 $ (410.5 ) $ 2,053.2 Operating expenses Contract drilling (exclusive of depreciation) 898.6 788.9 280.2 118.5 (280.2 ) 1,806.0 Loss on impairment 88.2 10.2 — — 5.6 104.0 Depreciation 378.6 212.4 40.3 — (21.6 ) 609.7 General and administrative — — 27.1 — 161.8 188.9 Equity in earnings of ARO — — — — (12.6 ) (12.6 ) Operating income (loss) $ (351.0 ) $ (176.9 ) $ 62.9 $ 85.7 $ (288.7 ) $ (668.0 ) Property and equipment, net $ 10,073.1 $ 4,322.7 $ 650.7 $ 701.1 $ (650.7 ) $ 15,096.9 Capital expenditures $ 31.4 $ 184.6 $ 27.5 $ — $ (16.5 ) $ 227.0 Year Ended December 31, 2018 Floaters Jackups ARO Other Reconciling Items Consolidated Total Revenues $ 1,013.5 $ 630.9 $ — $ 61.0 $ — $ 1,705.4 Operating expenses — Contract drilling (exclusive of depreciation) 737.4 526.5 — 55.5 — 1,319.4 Loss on impairment — 40.3 — — — 40.3 Depreciation 311.8 153.3 — — 13.8 478.9 General and administrative — — — — 102.7 102.7 Operating income (loss) $ (35.7 ) $ (89.2 ) $ — $ 5.5 $ (116.5 ) $ (235.9 ) Property and equipment, net $ 9,465.6 $ 3,114.1 $ — $ — $ 36.5 $ 12,616.2 Capital expenditures $ 105.5 $ 317.7 $ — $ — $ 3.5 $ 426.7 Year Ended December 31, 2017 Floaters Jackups ARO Other Reconciling Items Consolidated Total Revenues $ 1,143.5 $ 640.3 $ — $ 59.2 $ — $ 1,843.0 Operating expenses — Contract drilling (exclusive of depreciation) 624.2 512.1 — 53.2 — 1,189.5 Loss on impairment 174.7 8.2 — — — 182.9 Depreciation 297.4 131.5 — — 15.9 444.8 General and administrative — — — — 157.8 157.8 Operating income (loss) $ 47.2 $ (11.5 ) $ — $ 6.0 $ (173.7 ) $ (132.0 ) Property and equipment, net $ 9,650.9 $ 3,177.6 $ — $ — $ 45.2 $ 12,873.7 Capital expenditures $ 470.3 $ 62.1 $ — $ — $ 4.3 $ 536.7
Schedule Of Geographic Distribution Of Rigs By Segment	As of December 31, 2019 , the geographic distribution of our and ARO's drilling rigs was as follows: Floaters Jackups Other Total ARO North & South America 10 8 — 18 — Europe & the Mediterranean 7 14 — 21 — Middle East & Africa 4 12 9 25 7 Asia & Pacific Rim 3 7 — 10 — Asia & Pacific Rim (under construction) 2 — — 2 — Held-for-sale 1 2 — 3 — Total 27 43 9 79 7
Schedule Of Revenues And Long-Lived Assets By Geographical Segment	Information by country for those countries that account for more than 10% of our long-lived assets as well as the United Kingdom, our country of domicile, was as follows (in millions): Long-lived Assets 2019 2018 2017 Spain $ 3,012.4 $ 2,306.6 $ 2,004.2 United States 2,943.9 2,270.0 2,764.9 Saudi Arabia 1,257.7 668.6 93.6 United Kingdom 1,204.0 1,185.2 609.4 Nigeria 787.3 1,368.2 583.3 Singapore 22.6 23.9 2,859.3 Other countries 5,869.0 4,793.7 3,959.0 Total $ 15,096.9 $ 12,616.2 $ 12,873.7

Supplemental Financial Inform_2

Supplemental Financial Information (Tables)	12 Months Ended
	Dec. 31, 2019
Supplemental Financial Information [Abstract]
Accounts Receivable, Net	Accounts receivable, net, as of December 31, 2019 and 2018 consisted of the following (in millions): 2019 2018 Trade $ 466.4 $ 301.7 Other 60.3 46.4 526.7 348.1 Allowance for doubtful accounts (6.0 ) (3.4 ) $ 520.7 $ 344.7
Other Current Assets	Other current assets as of December 31, 2019 and 2018 consisted of the following (in millions): 2019 2018 Materials and supplies $ 340.1 $ 268.1 Prepaid taxes 36.2 35.0 Deferred costs 23.3 23.5 Prepaid expenses 13.5 15.2 Other 33.4 19.1 $ 446.5 $ 360.9
Other Assets, Net	Other assets as of December 31, 2019 and 2018 consisted of the following (in millions): 2019 2018 Right-of-use assets $ 58.1 $ — Tax receivables 36.3 8.4 Deferred tax assets 26.6 29.4 Supplemental executive retirement plan assets 26.0 27.2 Intangible assets 11.9 2.5 Deferred costs 7.1 13.5 Other 22.3 16.8 $ 188.3 $ 97.8
Accrued Liabilities And Other	Accrued liabilities and other as of December 31, 2019 and 2018 consisted of the following (in millions): 2019 2018 Personnel costs $ 134.4 $ 82.5 Accrued interest 115.2 100.6 Income and other taxes payable 61.2 36.9 Deferred revenue 30.0 56.9 Lease liabilities 21.1 — Other 55.8 41.1 $ 417.7 $ 318.0
Other Liabilities	Other liabilities as of December 31, 2019 and 2018 consisted of the following (in millions): 2019 2018 Unrecognized tax benefits (inclusive of interest and penalties) $ 323.1 $ 177.0 Pension and other post-retirement benefits 246.7 — Deferred tax liabilities 99.0 70.7 Intangible liabilities 52.1 53.5 Lease liabilities 51.8 — Supplemental executive retirement plan liabilities 26.7 28.1 Personnel costs 24.5 25.1 Deferred revenue 9.7 20.5 Other 33.8 21.1 $ 867.4 $ 396.0
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]	Accumulated other comprehensive income as of December 31, 2019 and 2018 consisted of the following (in millions): 2019 2018 Derivative instruments $ 22.6 $ 12.6 Pension and other post-retirement benefits (21.7 ) — Currency translation adjustment 7.1 7.3 Other (1.8 ) (1.7 ) $ 6.2 $ 18.2
Repair And Maintenance Expense Related To Continuing Operations	Repair and maintenance expense related to continuing operations for each of the years in the three-year period ended December 31, 2019 was as follows (in millions): 2019 2018 2017 Repair and maintenance expense $ 303.7 $ 198.4 $ 188.7
Schedule of Other Nonoperating Income, by Component [Table Text Block]	Other, net, for each of the years in the three-year period ended December 31, 2019 consisted of the following (in millions): 2019 2018 2017 Gain on bargain purchase and measurement period adjustments $ 637.0 $ 1.8 $ 140.2 SHI settlement 200.0 — — Gain (loss) on extinguishment of debt 194.1 (19.0 ) (2.6 ) Settlement of legal dispute (20.3 ) — — Currency translation adjustments (7.4 ) (17.2 ) (5.1 ) Other 1.0 (.4 ) 1.9 $ 1,004.4 $ (34.8 ) $ 134.4
Schedule of Cash Flows Information	Net cash provided by (used in) operating activities of continuing operations attributable to the net change in operating assets and liabilities for each of the years in the three-year period ended December 31, 2019 was as follows (in millions): 2019 2018 2017 (Increase) decrease in accounts receivable $ 29.5 $ (6.2 ) $ 83.2 Increase in other assets (32.0 ) (2.8 ) (14.0 ) Increase (Decrease) in liabilities (25.4 ) 2.7 3.2 $ (27.9 ) $ (6.3 ) $ 72.4
Cash Paid For Interest And Income Taxes	Cash paid for interest and income taxes for each of the years in the three-year period ended December 31, 2019 was as follows (in millions): 2019 2018 2017 Interest, net of amounts capitalized $ 410.0 $ 232.6 $ 199.8 Income taxes 107.6 58.4 62.8
Revenue from External Customers by Products and Services [Table Text Block]	Consolidated revenues by customer for the years ended December 31, 2019 , 2018 and 2017 were as follows: 2019 2018 2017 Total (1) 16 % 15 % 22 % BP (2) 9 % 7 % 15 % Saudi Aramco (3) 7 % 11 % 9 % Petrobras (4) 4 % 8 % 11 % Other 64 % 59 % 43 % 100 % 100 % 100 % (1) For the years ended December 31, 2019 , 93% of revenues provided by Total were attributable to the Floaters segment and the remainder was attributable to the Jackup segment. During the years 2018 and 2017 , all Total revenues were attributable to the Floater segment. (2) For the year ended December 31, 2019, 16% , 43% and 41% of BP revenues were attributable to our Floater, Other and Jackup segments, respectively. For the year ended December 31, 2018, 27% , 53% and 20% of BP revenues were attributable to our Floater, Other and Jackup segments, respectively. For the year ended December 31, 2017, 78% of BP revenues were attributable to our Floater segment and the remaining revenues were attributable to our Other segment. (3) For the years ended December 31, 2019, 2018 and 2017 , all Saudi Aramco revenues were attributable to the Jackup segment. (4) For the years ended December 31, 2019, 2018 and 2017 , all Petrobras revenues were attributable to the Floater segment.
Reconciliation of Revenue from Segments to Consolidated [Table Text Block]	Consolidated revenues by region, including the United Kingdom, our country of domicile, for the years ended December 31, 2019, 2018 and 2017 were as follows (in millions): 2019 2018 2017 Saudi Arabia (1) $ 313.4 $ 182.2 $ 171.8 U.S. Gulf of Mexico (2) 301.0 214.7 149.8 Angola (3) 284.0 285.7 445.7 United Kingdom (4) 213.1 192.6 164.6 Australia (5) 204.2 283.9 206.7 Brazil (6) 117.8 139.6 196.2 Egypt (7) 40.4 31.2 214.8 Other 579.3 375.5 293.4 $ 2,053.2 $ 1,705.4 $ 1,843.0 (1) For the years ended December 31, 2019 , 65% and 35% of revenues were attributable to our Jackup and Other segments, respectively. For the years ended December 31, 2018 and 2017 , all revenues earned were attributable to our Jackup segment. (2) For the years ended December 31, 2019, 2018 and 2017 , 46% , 30% and 29% of revenues earned in the U.S. Gulf of Mexico, respectively, were attributable to our Floaters segment, 28% , 42% and 31% of revenues were attributable to our Jackup segment, respectively, and the remaining revenues were attributable to our Other segment, respectively. (3) For the years ended December 31, 2019, 2018 and 2017 , 87% , 86% and 88% of revenues earned in Angola, respectively, were attributable to our Floaters segment with the remaining revenues attributable to our Jackup segment. (4) For the years ended December 31, 2019, 2018 and 2017 , all revenues earned in the United Kingdom were attributable to our Jackup segment. (5) For the years ended December 31, 2019, 2018 and 2017 , 90% , 92% and 87% of revenues earned in Australia, respectively, were attributable to our Floaters segment with the remaining revenues attributable to our Jackup segment. (6) For the years ended December 31, 2019, 2018 and 2017 , all revenues earned in Brazil were attributable to our Floaters segment. (7) For the years ended December 31, 2019, 2018 and 2017 , all revenues earned in Egypt were attributable to our Floaters segment.

Guarantee Of Registered Secur_2

Guarantee Of Registered Securities (Tables)	12 Months Ended
	Dec. 31, 2019
Guarantees [Abstract]
Condensed Consolidating Statements Of Income	VALARIS PLC AND SUBSIDIARIES Valaris plc ENSCO International Incorporated Pride International LLC Other Non-guarantor Subsidiaries of Valaris Consolidating Adjustments Total OPERATING REVENUES $ 56.7 $ 165.5 $ — $ 2,168.9 $ (337.9 ) $ 2,053.2 OPERATING EXPENSES Contract drilling (exclusive of depreciation) 82.6 147.1 — 1,914.2 (337.9 ) 1,806.0 Loss on impairment — — — 104.0 — 104.0 Depreciation .1 17.3 — 592.3 — 609.7 General and administrative 85.5 .4 — 103.0 — 188.9 168.2 164.8 — 2,713.5 (337.9 ) 2,708.6 EQUITY IN EARNINGS OF ARO — — — (12.6 ) — (12.6 ) OPERATING INCOME (LOSS) (111.5 ) 0.7 — (557.2 ) — (668.0 ) OTHER INCOME (EXPENSE), NET 723.9 (35.7 ) (80.8 ) (20.2 ) 17.0 604.2 INCOME (LOSS) FROM CONTINUING OPERATIONS BEFORE INCOME TAXES 612.4 (35.0 ) (80.8 ) (577.4 ) 17.0 (63.8 ) INCOME TAX EXPENSE — 39.8 — 88.6 — 128.4 EQUITY EARNINGS (LOSSES) IN AFFILIATES, NET OF TAX (810.4 ) 47.8 25.0 — 737.6 — NET LOSS (198.0 ) (27.0 ) (55.8 ) (666.0 ) 754.6 (192.2 ) NET INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS — — — (5.8 ) — (5.8 ) NET LOSS ATTRIBUTABLE TO VALARIS $ (198.0 ) $ (27.0 ) $ (55.8 ) $ (671.8 ) $ 754.6 $ (198.0 ) VALARIS PLC AND SUBSIDIARIES Valaris plc ENSCO International Incorporated Pride International LLC Other Non-guarantor Subsidiaries of Valaris Consolidating Adjustments Total OPERATING REVENUES $ 49.5 $ 155.2 $ — $ 1,802.8 $ (302.1 ) $ 1,705.4 OPERATING EXPENSES Contract drilling (exclusive of depreciation) 51.0 139.5 — 1,431.0 (302.1 ) 1,319.4 Loss on impairment — — — 40.3 — 40.3 Depreciation — 14.2 — 464.7 — 478.9 General and administrative 46.3 .4 — 56.0 — 102.7 OPERATING INCOME (LOSS) (47.8 ) 1.1 — (189.2 ) — (235.9 ) OTHER INCOME (EXPENSE), NET 2.7 (135.2 ) (89.0 ) (109.0 ) 27.5 (303.0 ) LOSS FROM CONTINUING OPERATIONS BEFORE INCOME TAXES (45.1 ) (134.1 ) (89.0 ) (298.2 ) 27.5 (538.9 ) INCOME TAX EXPENSE — 43.3 — 46.3 — 89.6 DISCONTINUED OPERATIONS, NET — — — (8.1 ) — (8.1 ) EQUITY EARNINGS (LOSSES) IN AFFILIATES, NET OF TAX (594.6 ) 121.8 93.3 — 379.5 — NET INCOME (LOSS) (639.7 ) (55.6 ) 4.3 (352.6 ) 407.0 (636.6 ) NET INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS — — — (3.1 ) — (3.1 ) NET INCOME (LOSS) ATTRIBUTABLE TO VALARIS $ (639.7 ) $ (55.6 ) $ 4.3 $ (355.7 ) $ 407.0 $ (639.7 ) VALARIS PLC AND SUBSIDIARIES Valaris plc ENSCO International Incorporated Pride International LLC Other Non-guarantor Subsidiaries of Valaris Consolidating Adjustments Total OPERATING REVENUES $ 52.9 $ 163.3 $ — $ 1,941.2 $ (314.4 ) $ 1,843.0 OPERATING EXPENSES Contract drilling (exclusive of depreciation) 50.0 149.9 — 1,304.0 (314.4 ) 1,189.5 Loss on impairment — — — 182.9 — 182.9 Depreciation — 15.9 — 428.9 — 444.8 General and administrative 45.4 50.8 — 61.6 — 157.8 OPERATING LOSS (42.5 ) (53.3 ) — (36.2 ) — (132.0 ) OTHER INCOME (EXPENSE), NET (6.8 ) (110.5 ) (71.7 ) 110.5 14.5 (64.0 ) INCOME (LOSS) FROM CONTINUING OPERATIONS BEFORE INCOME TAXES (49.3 ) (163.8 ) (71.7 ) 74.3 14.5 (196.0 ) INCOME TAX EXPENSE — 45.0 — 64.2 — 109.2 DISCONTINUED OPERATIONS, NET — — — 1.0 — 1.0 EQUITY EARNINGS (LOSSES) IN AFFILIATES, NET OF TAX (254.4 ) 129.6 84.2 — 40.6 — NET INCOME (LOSS) (303.7 ) (79.2 ) 12.5 11.1 55.1 (304.2 ) NET LOSS ATTRIBUTABLE TO NONCONTROLLING INTERESTS — — — .5 — .5 NET INCOME (LOSS) ATTRIBUTABLE TO VALARIS $ (303.7 ) $ (79.2 ) $ 12.5 $ 11.6 $ 55.1 $ (303.7 )
Schedule of Condensed Consolidated Statements of Comprehensive Income	PLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME Year Ended December 31, 2019 (in millions) Valaris plc ENSCO International Incorporated Pride International LLC Other Non-Guarantor Subsidiaries of Valaris Consolidating Adjustments Total NET LOSS $ (198.0 ) $ (27.0 ) $ (55.8 ) $ (666.0 ) $ 754.6 $ (192.2 ) OTHER COMPREHENSIVE INCOME (LOSS), NET Net changes in pension and other postretirement plan assets and benefit obligations recognized in other comprehensive loss, net of income tax benefits of ($5.9 million) — — — (21.7 ) — $ (21.7 ) Net change in fair value of derivatives — 1.6 — — — 1.6 Reclassification of net gains on derivative instruments from other comprehensive loss into net loss — 8.3 — — — 8.3 Other — — — (.2 ) — (.2 ) NET OTHER COMPREHENSIVE INCOME (LOSS) — 9.9 — (21.9 ) — (12.0 ) COMPREHENSIVE LOSS (198.0 ) (17.1 ) (55.8 ) (687.9 ) 754.6 (204.2 ) COMPREHENSIVE INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS — — — (5.8 ) — (5.8 ) COMPREHENSIVE LOSS ATTRIBUTABLE TO VALARIS $ (198.0 ) $ (17.1 ) $ (55.8 ) $ (693.7 ) $ 754.6 $ (210.0 ) VALARIS PLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME Year Ended December 31, 2018 (in millions) ENSCO International Incorporated Pride International LLC Other Non-Guarantor Subsidiaries of Valaris Consolidating Adjustments Total NET INCOME (LOSS) $ (639.7 ) $ (55.6 ) $ 4.3 $ (352.6 ) $ 407.0 $ (636.6 ) OTHER COMPREHENSIVE LOSS, NET Net change in fair value of derivatives — (9.7 ) — — — (9.7 ) Reclassification of net losses on derivative instruments from other comprehensive income into net income — (1.0 ) — — — (1.0 ) Other — — — (.5 ) — (.5 ) NET OTHER COMPREHENSIVE LOSS — (10.7 ) — (.5 ) — (11.2 ) COMPREHENSIVE INCOME (LOSS) (639.7 ) (66.3 ) 4.3 (353.1 ) 407.0 (647.8 ) COMPREHENSIVE INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS — — — (3.1 ) — (3.1 ) COMPREHENSIVE INCOME (LOSS) ATTRIBUTABLE TO VALARIS $ (639.7 ) $ (66.3 ) $ 4.3 $ (356.2 ) $ 407.0 $ (650.9 ) VALARIS PLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME Year Ended December 31, 2017 (in millions) ENSCO International Incorporated Pride International LLC Other Non-Guarantor Subsidiaries of Valaris Consolidating Adjustments Total NET INCOME (LOSS) $ (303.7 ) $ (79.2 ) $ 12.5 $ 11.1 $ 55.1 $ (304.2 ) OTHER COMPREHENSIVE INCOME, NET Net change in fair value of derivatives — 8.5 — — — 8.5 Reclassification of net gains on derivative instruments from other comprehensive income into net loss — .4 — — — .4 Other — — — .7 — .7 NET OTHER COMPREHENSIVE INCOME — 8.9 — .7 — 9.6 COMPREHENSIVE INCOME (LOSS) (303.7 ) (70.3 ) 12.5 11.8 55.1 (294.6 ) COMPREHENSIVE LOSS ATTRIBUTABLE TO NONCONTROLLING INTERESTS — — — .5 — .5 COMPREHENSIVE INCOME (LOSS) ATTRIBUTABLE TO VALARIS $ (303.7 ) $ (70.3 ) $ 12.5 $ 12.3 $ 55.1 $ (294.1 )
Condensed Consolidating Balance Sheets	VALARIS PLC AND SUBSIDIARIES Valaris plc ENSCO International Incorporated Pride International LLC Other Consolidating Adjustments Total ASSETS CURRENT ASSETS Cash and cash equivalents $ 21.5 $ — $ — $ 75.7 $ — $ 97.2 Short-term investments — — — Accounts receivable, net 0.2 19.7 500.8 — 520.7 Accounts receivable from affiliates 4,031.4 386.0 897.2 (5,314.6 ) — Other .6 11.6 434.3 446.5 Total current assets 4,053.7 417.3 — 1,908.0 (5,314.6 ) 1,064.4 PROPERTY AND EQUIPMENT, AT COST 1.9 108.8 18,283.1 18,393.8 Less accumulated depreciation 1.9 84.7 3,210.3 3,296.9 Property and equipment, net — 24.1 — 15,072.8 — 15,096.9 SHAREHOLDER NOTE FROM ARO — — — 452.9 — 452.9 INVESTMENT IN ARO — — — 128.7 — 128.7 DUE FROM AFFILIATES 73.8 — 38.9 1,775.7 (1,888.4 ) — INVESTMENTS IN AFFILIATES 9,778.5 788.8 1,224.9 — (11,792.2 ) — OTHER ASSETS 7.9 3.8 — 182.6 (6.0 ) 188.3 $ 13,913.9 $ 1,234.0 $ 1,263.8 $ 19,520.7 $ (19,001.2 ) $ 16,931.2 LIABILITIES AND SHAREHOLDERS' EQUITY CURRENT LIABILITIES Accounts payable and accrued liabilities $ 99.2 $ 29.3 $ 12.2 $ 565.2 $ — $ 705.9 Accounts payable to affiliates 818.8 147.8 815.1 3,532.9 (5,314.6 ) — Current maturities of long - term debt — — 124.8 — — 124.8 Total current liabilities 918.0 177.1 952.1 4,098.1 (5,314.6 ) 830.7 DUE TO AFFILIATES 710.3 478.8 586.6 112.7 (1,888.4 ) — LONG-TERM DEBT 2,990.6 111.7 373.3 2,447.9 — 5,923.5 OTHER LIABILITIES (14.6 ) 90.6 — 797.4 (6.0 ) 867.4 VALARIS SHAREHOLDERS' EQUITY (DEFICIT) 9,309.6 375.8 (648.2 ) 12,065.9 (11,792.2 ) 9,310.9 NONCONTROLLING INTERESTS — — — (1.3 ) — (1.3 ) Total equity (deficit) 9,309.6 375.8 (648.2 ) 12,064.6 (11,792.2 ) 9,309.6 $ 13,913.9 $ 1,234.0 $ 1,263.8 $ 19,520.7 $ (19,001.2 ) $ 16,931.2 VALARIS PLC AND SUBSIDIARIES Valaris plc ENSCO International Incorporated Pride International LLC Other Consolidating Adjustments Total ASSETS CURRENT ASSETS Cash and cash equivalents $ 199.8 $ — $ 2.7 $ 72.6 $ — $ 275.1 Short-term investments 329.0 — — — — 329.0 Accounts receivable, net 7.3 25.4 — 312.0 — 344.7 Accounts receivable from affiliates 1,861.2 171.4 — 131.7 (2,164.3 ) — Other .6 6.0 — 354.3 — 360.9 Total current assets 2,397.9 202.8 2.7 870.6 (2,164.3 ) 1,309.7 PROPERTY AND EQUIPMENT, AT COST 1.8 125.2 — 15,390.0 — 15,517.0 Less accumulated depreciation 1.8 91.3 — 2,807.7 — 2,900.8 Property and equipment, net — 33.9 — 12,582.3 — 12,616.2 DUE FROM AFFILIATES 2,413.8 234.5 125.0 2,715.1 (5,488.4 ) — INVESTMENTS IN AFFILIATES 8,522.6 3,713.7 1,199.9 — (13,436.2 ) — OTHER ASSETS 8.1 — — 89.7 — 97.8 $ 13,342.4 $ 4,184.9 $ 1,327.6 $ 16,257.7 $ (21,088.9 ) $ 14,023.7 LIABILITIES AND SHAREHOLDERS' EQUITY CURRENT LIABILITIES Accounts payable and accrued liabilities $ 85.3 $ 32.0 $ 12.7 $ 398.5 $ — $ 528.5 Accounts payable to affiliates 59.7 139.5 38.2 1,926.9 (2,164.3 ) — Total current liabilities 145.0 171.5 50.9 2,325.4 (2,164.3 ) 528.5 DUE TO AFFILIATES 1,432.0 1,226.9 1,366.5 1,463.0 (5,488.4 ) — LONG-TERM DEBT 3,676.5 149.3 502.6 682.0 — 5,010.4 OTHER LIABILITIES 0.1 64.3 — 331.6 — 396.0 VALARIS SHAREHOLDERS' EQUITY (DEFICIT) 8,088.8 2,572.9 (592.4 ) 11,458.3 (13,436.2 ) 8,091.4 NONCONTROLLING INTERESTS — — — (2.6 ) — (2.6 ) Total equity (deficit) 8,088.8 2,572.9 (592.4 ) 11,455.7 (13,436.2 ) 8,088.8 $ 13,342.4 $ 4,184.9 $ 1,327.6 $ 16,257.7 $ (21,088.9 ) $ 14,023.7
Condensed Consolidating Statements Of Cash Flows	VALARIS PLC AND SUBSIDIARIES Valaris plc ENSCO International Incorporated Pride International LLC Other Non-guarantor Subsidiaries of Valaris Consolidating Adjustments Total OPERATING ACTIVITIES Net cash provided by (used in) operating activities of continuing operations $ (181.2 ) $ (57.9 ) $ (111.3 ) $ 73.5 $ — $ (276.9 ) INVESTING ACTIVITIES Acquisition of Rowan, net of cash acquired — — — 931.9 — 931.9 Maturities of short-term investments 474.0 — — — — 474.0 Purchases of short-term investments (145.0 ) — — — — (145.0 ) Additions to property and equipment — — — (227.0 ) — (227.0 ) Net proceeds from disposition of assets — — 17.7 — 17.7 Other (.1 ) — — .1 — — Net cash provided by investing activities of continuing operations 328.9 — — 722.7 — 1,051.6 FINANCING ACTIVITIES Reduction of long-term borrowings (536.6 ) (30.4 ) — (361.1 ) — (928.1 ) Borrowings on credit facility 215.0 — — — — 215.0 Repayments of credit facility borrowings (215.0 ) — — — — (215.0 ) Advances from (to) affiliates 220.6 88.3 108.6 (417.5 ) — — Debt solicitation fees — — — (9.5 ) — (9.5 ) Cash dividends paid (4.5 ) — — — — (4.5 ) Other (5.5 ) — — (4.7 ) — (10.2 ) Net cash provided by (used in) financing activities (326.0 ) 57.9 108.6 (792.8 ) — (952.3 ) Effect of exchange rate changes on cash and cash equivalents — — — (.3 ) — (.3 ) NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS (178.3 ) — (2.7 ) 3.1 — (177.9 ) CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR 199.8 — 2.7 72.6 — 275.1 CASH AND CASH EQUIVALENTS, END OF YEAR $ 21.5 $ — $ — $ 75.7 $ — $ 97.2 VALARIS PLC AND SUBSIDIARIES Valaris plc ENSCO International Incorporated Pride International LLC Other Non-guarantor Subsidiaries of Valaris Consolidating Adjustments Total OPERATING ACTIVITIES Net cash provided by (used in) operating activities of continuing operations $ 18.1 $ (135.1 ) $ (97.6 ) $ 158.9 $ — $ (55.7 ) INVESTING ACTIVITIES Maturities of short-term investments 1,030.0 — — — — 1,030.0 Purchases of short-term investments (919.0 ) — — — — (919.0 ) Additions to property and equipment — — — (426.7 ) — (426.7 ) Net proceeds from disposition of assets — — — 11.0 — 11.0 Purchase of affiliate debt (551.7 ) — — — 551.7 — Sale of affiliate debt 479.0 — — — (479.0 ) — Net cash provided by (used in) investing activities of continuing operations 38.3 — — (415.7 ) 72.7 (304.7 ) FINANCING ACTIVITIES Proceeds from issuance of senior notes 1,000.0 — — — — 1,000.0 Advances from (to) affiliates (845.0 ) 135.1 612.5 97.4 — — Reduction of long-term borrowings (159.9 ) — (537.8 ) (0.8 ) (72.7 ) (771.2 ) Debt issuance costs (17.0 ) — — — — (17.0 ) Cash dividends paid (17.9 ) — — — — (17.9 ) Other (2.0 ) — — (3.7 ) — (5.7 ) Net cash provided by (used in) financing activities (41.8 ) 135.1 74.7 92.9 (72.7 ) 188.2 Net cash provided by discontinued operations — — — 2.5 — 2.5 Effect of exchange rate changes on cash and cash equivalents — — — (.6 ) — (.6 ) NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS 14.6 — (22.9 ) (162.0 ) — (170.3 ) CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR 185.2 — 25.6 234.6 — 445.4 CASH AND CASH EQUIVALENTS, END OF YEAR $ 199.8 $ — $ 2.7 $ 72.6 $ — $ 275.1 VALARIS PLC AND SUBSIDIARIES Valaris plc ENSCO International Incorporated Pride International LLC Other Non-guarantor Subsidiaries of Valaris Consolidating Adjustments Total OPERATING ACTIVITIES Net cash provided by (used in) operating activities of continuing operations $ (18.2 ) $ (117.6 ) $ (100.1 ) $ 495.3 $ — $ 259.4 INVESTING ACTIVITIES Purchases of short-term investments (1,022.9 ) — — (17.1 ) — (1,040.0 ) Additions to property and equipment — — — (536.7 ) — (536.7 ) Maturities of short-term investments 1,748.0 5.5 — 289.0 — 2,042.5 Net proceeds from disposition of assets — — — 2.8 — 2.8 Purchase of affiliate debt (316.3 ) — — — 316.3 — Acquisition of Atwood, net of cash acquired — — — (871.6 ) — (871.6 ) Net cash provided by (used in) investing activities of continuing operations 408.8 5.5 — (1,133.6 ) 316.3 (403.0 ) FINANCING ACTIVITIES Reduction of long-term borrowing (220.7 ) — — — (316.3 ) (537.0 ) Cash dividends paid (13.8 ) — — — — (13.8 ) Debt issuance costs (12.0 ) — — — — (12.0 ) Advances from (to) affiliates (848.9 ) 112.1 105.9 630.9 — — Other (2.6 ) — — (5.1 ) — (7.7 ) Net cash provided by (used in) financing activities (1,098.0 ) 112.1 105.9 625.8 (316.3 ) (570.5 ) Net cash used in discontinued operations — — — (.8 ) — (.8 ) Effect of exchange rate changes on cash and cash equivalents — — — .6 — .6 NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS (707.4 ) — 5.8 (12.7 ) — (714.3 ) CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR 892.6 — 19.8 247.3 — 1,159.7 CASH AND CASH EQUIVALENTS, END OF YEAR $ 185.2 $ — $ 25.6 $ 234.6 $ — $ 445.4

Unaudited Quarterly Financial_2

Unaudited Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2019
Quarterly Financial Data [Abstract]
Summary Of Unaudited Quarterly Consolidated Income Statement	The following tables summarize our unaudited quarterly condensed consolidated income statement data for the years ended December 31, 2019 and 2018 (in millions, except per share amounts): 2019 First Quarter Second Quarter Third Quarter Fourth Quarter Year Operating revenues $ 405.9 $ 583.9 $ 551.3 $ 512.1 $ 2,053.2 Operating expenses Contract drilling (exclusive of depreciation) 332.6 500.3 496.5 476.6 1,806.0 Loss on impairment (1) — 2.5 88.2 13.3 104.0 Depreciation 125.0 157.9 163.0 163.8 609.7 General and administrative 29.6 81.2 36.1 42.0 188.9 Equity in earnings of ARO — 0.6 (3.7 ) (9.5 ) (12.6 ) Operating loss (81.3 ) (157.4 ) (236.2 ) (193.1 ) (668.0 ) Other income (expense), net (75.2 ) 597.3 40.2 41.9 604.2 Income (loss) from continuing operations before income taxes (156.5 ) 439.9 (196.0 ) (151.2 ) (63.8 ) Income tax expense 31.5 32.6 1.5 62.8 128.4 Net income (loss) (188.0 ) 407.3 (197.5 ) (214.0 ) (192.2 ) Net (income) loss attributable to noncontrolling interests (2.4 ) (1.8 ) .4 (2.0 ) (5.8 ) Net income (loss) attributable to Valaris $ (190.4 ) $ 405.5 $ (197.1 ) $ (216.0 ) $ (198.0 ) Income (loss) per share – basic and diluted Continuing operations $ (1.75 ) $ 2.09 $ (1.00 ) $ (1.09 ) $ (1.14 ) Discontinued operations — — — — — $ (1.75 ) $ 2.09 $ (1.00 ) $ (1.09 ) $ (1.14 ) (1) The quarterly periods included losses associated with the impairment of older, less capable, non-core rigs and operating lease impairments. See " Note 6 - Property and Equipment" and " Note 14 - Leases" for additional information. 2018 First Quarter Second Quarter Third Quarter Fourth Quarter Year Operating revenues $ 417.0 $ 458.5 $ 430.9 $ 399.0 $ 1,705.4 Operating expenses Contract drilling (exclusive of depreciation) 325.2 344.3 327.1 322.8 1,319.4 Loss on impairment (1) — — — 40.3 40.3 Depreciation 115.2 120.7 120.6 122.4 478.9 General and administrative 27.9 26.1 25.1 23.6 102.7 Operating loss (51.3 ) (32.6 ) (41.9 ) (110.1 ) (235.9 ) Other expense, net (70.7 ) (84.8 ) (77.7 ) (69.8 ) (303.0 ) Loss from continuing operations before income taxes (122.0 ) (117.4 ) (119.6 ) (179.9 ) (538.9 ) Income tax expense 18.4 24.7 23.3 23.2 89.6 Loss from continuing operations (140.4 ) (142.1 ) (142.9 ) (203.1 ) (628.5 ) Loss from discontinued operations, net (.1 ) (8.0 ) — — (8.1 ) Net loss (140.5 ) (150.1 ) (142.9 ) (203.1 ) (636.6 ) Net (income) loss attributable to noncontrolling interests .4 (.9 ) (2.1 ) (.5 ) (3.1 ) Net loss attributable to Valaris $ (140.1 ) $ (151.0 ) $ (145.0 ) $ (203.6 ) $ (639.7 ) Loss per share – basic and diluted Continuing operations $ (1.29 ) $ (1.31 ) $ (1.34 ) $ (1.88 ) $ (5.82 ) Discontinued operations — (0.08 ) — — (0.08 ) $ (1.29 ) $ (1.39 ) $ (1.34 ) $ (1.88 ) $ (5.90 ) (1) Fourth quarter included an aggregate loss of $40.3 million associated with the impairment of an older, non-core jackup rig. See " Note 6 - Property and Equipment" for additional information.

Description Of The Business A_4

Description Of The Business And Summary Of Significant Accounting Policies (Narrative) (Details) $ / shares in Units, $ in Millions

Apr. 11, 2019USD ($)rigs$ / sharesshares

Oct. 06, 2017

Dec. 31, 2019USD ($)

Sep. 30, 2019USD ($)

Jun. 30, 2019USD ($)

Mar. 31, 2019USD ($)

Dec. 31, 2018USD ($)$ / shares

Sep. 30, 2018USD ($)

Jun. 30, 2018USD ($)

Mar. 31, 2018USD ($)

Dec. 31, 2019USD ($)drillshipjackuprigsshares

Dec. 31, 2018USD ($)$ / sharesshares

Dec. 31, 2017USD ($)shares

Dec. 31, 2019$ / shares

Dec. 31, 2019USD ($)

Dec. 31, 2019jackup

Dec. 31, 2019continent

Dec. 31, 2019rigs

Dec. 31, 2019country

Apr. 10, 2019$ / shares

Jan. 01, 2019USD ($)

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Number of contract drilling rigs

74

Number of jackups leased by ARO

9

9

9

Number of different countries having drilling contracts spanning | country

24

Number of different continents having drilling contracts | continent

6

Number of Rigs Owned by ARO

7

7

Net foreign currency exchange gains (losses) | $

$ (7.4)

$ (17.2)

$ (5.1)

Short-term Investments | $

$ 329

329

$ 0

Asset Impairment Charges | $

$ 13.3

$ 88.2

$ 2.5

$ 0

40.3

$ 0

$ 0

$ 0

$ 104

$ 40.3

$ 182.9

Antidilutive share options excluded from computation of diluted earnings per share | shares

300,000

1,500,000

2,000,000

Operating Lease, Liability | $

72.9

Operating Lease, Right-of-Use Asset | $

$ 0

$ 0

$ 58.1

Three Percent Senior Notes Due Two Thousand Twenty Four [Member] | Senior Notes [Member]

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Debt instrument, interest rate, stated percentage

3.00%

3.00%

Common Class A [Member]

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Common Stock, Par or Stated Value Per Share | $ / shares

$ 0.40

$ 0.40

$ 0.40

Rowan Companies [Member]

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Business Acquisition, Equity Interest Issued or Issuable, Value Assigned, Per Share | $ / shares

$ 43.67

Consideration transferred | $

$ 1,400

$ 1,402.8

Rowan Companies [Member] | Common Class A [Member]

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Entity shares issued per acquiree share | shares

2.750

Shares Issued, Price Per Share | $ / shares

$ 15.88

Business Acquisition, Equity Interest Issued or Issuable, Value Assigned, Per Share | $ / shares

$ 2.75

Number of ordinary shares | shares

88,300,000

Common Stock, Par or Stated Value Per Share | $ / shares

$ 0.40

$ 0.10

Ultra Deepwater Drillships [Member] | Rowan Companies [Member]

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Number of contract drilling rigs

4

Jackup Rigs [Member]

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Number of contract drilling rigs

50

Jackup Rigs [Member] | Rowan Companies [Member]

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Number of contract drilling rigs

19

19

Held-for-sale

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Number of contract drilling rigs

1

Held-for-sale | Rowan Companies [Member]

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Number of contract drilling rigs

2

Drilling rigs and equipment [Member] | Minimum

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Property, Plant and Equipment, Useful Life

4 years

Drilling rigs and equipment [Member] | Maximum

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Property, Plant and Equipment, Useful Life

35 years

Drilling rigs and equipment [Member] | Rowan Companies [Member]

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Number of contract drilling rigs | drillship

4

Drilling rigs and equipment [Member] | Rowan Companies [Member] | Minimum

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Property, Plant and Equipment, Useful Life

30 years

16 years

Drilling rigs and equipment [Member] | Rowan Companies [Member] | Maximum

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Property, Plant and Equipment, Useful Life

35 years

35 years

Building and Building Improvements [Member] | Minimum

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Property, Plant and Equipment, Useful Life

7 years

Building and Building Improvements [Member] | Maximum

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Property, Plant and Equipment, Useful Life

30 years

Equipment [Member] | Minimum

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Property, Plant and Equipment, Useful Life

3 years

Equipment [Member] | Maximum

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Property, Plant and Equipment, Useful Life

6 years

Accounting Standards Update 2016-02 [Member]

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Operating Lease, Liability | $

$ 64.6

Operating Lease, Right-of-Use Asset | $

$ 53.7

Floaters [Member] | Asset under Construction [Member]

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Number of contract drilling rigs

2

Floaters [Member] | Ultra Deepwater Drillships [Member]

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Number of contract drilling rigs

16

Floaters [Member] | Dynamically Positioned Semisubmersible [Member]

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Number of contract drilling rigs

8

Floaters [Member] | Moored Semisubmersible Rigs [Member]

Description Of The Business And Summary Of Significant Accounting Policies [Line Items]

Number of contract drilling rigs

2

Description Of The Business A_5

Description Of The Business And Summary Of Significant Accounting Policies (Schedule Of Income From Continuing Operations Attributable To Ensco) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Income (loss) from continuing operations attributable to Ensco	$ (198)	$ (631.6)	$ (304.7)
Income from continuing operations allocated to non-vested share awards	(0.1)	(0.5)	(0.4)
Income (loss) from continuing operations attributable to Ensco shares	$ (198.1)	$ (632.1)	$ (305.1)

Revenue from Contracts with C_2

Revenue from Contracts with Customers Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Revenue, Performance Obligation, Description of Timing	The remaining duration of our drilling contracts based on those in place as of December 31, 2019 was between approximately one month and four years.
Capitalized Contract Cost, Net	$ 30.5
Upfront Rig Mobilizations And Certain Contract Preparation [Member]
Disaggregation of Revenue [Line Items]
Capitalized Contract Cost, Net	19.7	$ 23.5
Capitalized Contract Cost, Amortization	42.1	34	$ 28.1
Deferred Certification Costs [Member]
Disaggregation of Revenue [Line Items]
Capitalized Contract Cost, Net	10.8	13.6
Capitalized Contract Cost, Amortization	$ 10.3	$ 12.4	$ 12.1

Revenue from Contracts with C_3

Revenue from Contracts with Customers Components of Contract Assets and Contract Liabilities (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Contract with Customer, Asset, Net, Current	$ 3.5	$ 3.5	$ 4
Contract with Customer, Liability, Current	30	30	56.9
Contract with Customer, Liability, Noncurrent	9.7	9.7	$ 20.5
Change in Contract With Customer, Asset [Roll Forward]
Contract with Customer, Asset, after Allowance for Credit Loss		4
Contract with Customer, Asset, Increase (Decrease) for Contract Acquired in Business Combination	8.4
Contract with Customer, Asset, Cumulative Catch-up Adjustment to Revenue, Change in Measure of Progress		1.3
Contract with Customer, Asset, Reclassified to Receivable		(10.2)
Contract with Customer, Asset, after Allowance for Credit Loss	3.5	3.5
Change in Contract With Customer, Liability [Roll Forward]
Contract with Customer, Liability		77.4
Contract with Customer, Liability, Increase (Decrease) for Contract Acquired in Business Combination	5.3
Contract with Customer, Liability, Increase from Cash Receipts		42.9
Contract with Customer, Liability, Revenue Recognized, Included In Beginning Balance		(56.3)
Contract with Customer, Liability, Revenue Recognized, Added During Period		(29.6)
Contract with Customer, Liability	$ 39.7	$ 39.7

Revenue from Contracts with C_4

Revenue from Contracts with Customers Future Amortization of Contract Liabilities and Deferred Costs (Details) $ in Millions	Dec. 31, 2019USD ($)
Revenue from Contract with Customer [Abstract]
Revenue, Remaining Performance Obligation, Amount	$ 39.7
Capitalized Contract Cost, Amortization Expense, Next Fiscal Year	23.2
Capitalized Contract Cost, Amortization Expense, Year Two	5.7
Capitalized Contract Cost, Amortization Expense, Year Three	1.2
Deferred contract costs	30.5
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01
Revenue from Contract with Customer [Abstract]
Revenue, Remaining Performance Obligation, Amount	$ 30
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue from Contract with Customer [Abstract]
Revenue, Remaining Performance Obligation, Amount	$ 7.8
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue from Contract with Customer [Abstract]
Revenue, Remaining Performance Obligation, Amount	$ 1.9
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue from Contract with Customer [Abstract]
Revenue, Remaining Performance Obligation, Amount	$ 0
Capitalized Contract Cost, Amortization Expense, Year Four and Thereafter	$ 0.4

Rowan Transaction Narrative (De

Rowan Transaction Narrative (Details) $ / shares in Units, € in Millions, shares in Millions, $ in Millions	Apr. 11, 2019EUR (€)rigsshares	Apr. 11, 2019USD ($)rigs$ / sharesshares	Oct. 06, 2017	Dec. 31, 2019USD ($)$ / shares	Sep. 30, 2019USD ($)	Jun. 30, 2019USD ($)	Mar. 31, 2019USD ($)	Dec. 31, 2018USD ($)$ / shares	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019EUR (€)drillshipjackuprigs	Dec. 31, 2019USD ($)drillshipjackuprigs$ / shares	Dec. 31, 2018USD ($)$ / shares	Dec. 31, 2017USD ($)	Apr. 10, 2019$ / shares	Oct. 05, 2018$ / shares
Business Acquisition [Line Items]
Number of contract drilling rigs | rigs														74	74
Unrecognized Tax Benefits, Increase Resulting from Acquisition															$ 149.9	$ 0
Tax Assessment					$ 42
Deferred Tax Liabilities, Net				$ 39.9				$ 34.8							39.9	34.8
OPERATING REVENUES				512.1	551.3	$ 583.9	$ 405.9	399	$ 430.9	$ 458.5	$ 417				2,053.2	1,705.4	$ 1,843
NET LOSS ATTRIBUTABLE TO VALARIS				$ (216)	$ (197.1)	$ 405.5	$ (190.4)	$ (203.6)	$ (145)	$ (151)	$ (140.1)				$ (198)	$ (639.7)	$ (303.7)
Class A Ordinary Shares, U.S. [Member]
Business Acquisition [Line Items]
Common Stock, Par or Stated Value Per Share | $ / shares				$ 0.40				$ 0.40							$ 0.40	$ 0.40
Rowan Companies [Member]
Business Acquisition [Line Items]
Common stock, value (in usd per share) | $ / shares		$ 43.67
Consideration transferred		$ 1,400													$ 1,402.8
Fair Value of Employee Equity awards		2.6
Merger related costs															18
Materials And Supplies				$ 83											83
Property and equipment				2,964											2,964
Intangible assets, net		16.2		11.9											11.9
Intangible Liabilities		2.1		1.4											1.4
Asset amortization															$ 3.6
Finite-Lived Intangible Assets, Remaining Amortization Period														2 years	2 years
Deferred Tax Assets, Net				99											$ 99
Unrecognized Tax Benefits, Increase Resulting from Acquisition		50.4
OPERATING REVENUES															448
NET LOSS ATTRIBUTABLE TO VALARIS															122.7
Rowan Companies [Member] | Luxembourg Inland Revenue [Member]
Business Acquisition [Line Items]
Unrecognized tax benefit, maximum exposure														€ 142	159
Deferred Other Tax Expense (Benefit)	€ 46	$ 52.6												47	52
Tax Assessment | €														€ 93
Deferred Tax Liabilities, Net				$ 104.6											$ 104.6
Rowan Companies [Member] | Forecast [Member]
Business Acquisition [Line Items]
Capitalized Contract Cost, Amortization												$ 5.4	$ 5.1
Rowan Companies [Member] | Class A Ordinary Shares, U.S. [Member]
Business Acquisition [Line Items]
Common stock, value (in usd per share) | $ / shares		$ 2.75
Shares Issued, Price Per Share | $ / shares		$ 15.88
Number of ordinary shares | shares	88.3	88.3
Common Stock, Par or Stated Value Per Share | $ / shares		$ 0.40																$ 0.10
Share Price | $ / shares																			$ 33.92
Jackup Rigs [Member]
Business Acquisition [Line Items]
Number of contract drilling rigs | rigs														50	50
Jackup Rigs [Member] | Rowan Companies [Member]
Business Acquisition [Line Items]
Number of contract drilling rigs	19	19												19	19
Drilling rigs and equipment [Member] | Rowan Companies [Member]
Business Acquisition [Line Items]
Number of contract drilling rigs | drillship														4	4
Minimum | Drilling rigs and equipment [Member]
Business Acquisition [Line Items]
Property, Plant and Equipment, Useful Life														4 years	4 years
Minimum | Drilling rigs and equipment [Member] | Rowan Companies [Member]
Business Acquisition [Line Items]
Property, Plant and Equipment, Useful Life			30 years											16 years	16 years
Maximum | Drilling rigs and equipment [Member]
Business Acquisition [Line Items]
Property, Plant and Equipment, Useful Life														35 years	35 years
Maximum | Drilling rigs and equipment [Member] | Rowan Companies [Member]
Business Acquisition [Line Items]
Property, Plant and Equipment, Useful Life			35 years											35 years	35 years

Rowan Transaction Assets Acquir

Rowan Transaction Assets Acquired Liabilities Assumed (Details) - USD ($) $ in Millions	Apr. 11, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Liabilities:
Current Portion of Long term debt		$ 203.2
Long-term Debt		1,910.9
Bargain purchase gain		637	$ 1.8	$ 140.2
Rowan Companies [Member]
Business Acquisition [Line Items]
Business Combination, Acquired Receivables, Gross Contractual Amount	$ 208.3
Assets:
Cash and cash equivalents		931.9
Accounts Receivable		203.5
Other current assets		99.2
Long -term notes receivable from ARO		454.5
Investment in ARO		141.3
Property and equipment		2,964
Other assets		43
Liabilities:
Accounts payable and accrued liabilities		273.1
Other liabilities		410.4
Net assets acquired		2,039.8
Less: Merger consideration	(1,400)	(1,402.8)
Bargain purchase gain		637
Rowan Companies [Member] | Previously Reported [Member]
Assets:
Cash and cash equivalents	931.9
Accounts Receivable	207.1
Other current assets	101.6
Long -term notes receivable from ARO	454.5
Investment in ARO	138.8
Property and equipment	2,989.8
Other assets	41.7
Liabilities:
Accounts payable and accrued liabilities	203.2
Current Portion of Long term debt	259.4
Long-term Debt	1,910.9
Other liabilities	376.3
Net assets acquired	2,115.6
Less: Merger consideration	(1,402.8)
Bargain purchase gain	$ 712.8
Rowan Companies [Member] | Restatement Adjustment [Member]
Assets:
Cash and cash equivalents		0
Accounts Receivable		(3.6)
Other current assets		(2.4)
Long -term notes receivable from ARO		0
Investment in ARO		2.5
Property and equipment		(25.8)
Other assets		1.3
Liabilities:
Accounts payable and accrued liabilities		0
Current Portion of Long term debt		13.7
Long-term Debt		0
Other liabilities		34.1
Net assets acquired		(75.8)
Less: Merger consideration		0
Bargain purchase gain		$ (75.8)

Rowan Transaction Pro Forma (De

Rowan Transaction Pro Forma (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Earnings per share - basic and diluted (in usd per share)	$ (1.09)	$ (1)	$ 2.09	$ (1.75)	$ (1.88)	$ (1.34)	$ (1.39)	$ (1.29)	$ (1.14)	$ (5.90)	$ (3.66)
Bargain purchase gain									$ 637	$ 1.8	$ 140.2
Rowan Companies [Member]
Business Acquisition [Line Items]
Revenues									2,240.5	2,530.4
Net loss									$ (994.3)	$ (796.5)
Earnings per share - basic and diluted (in usd per share)									$ (3.80)	$ (4.05)
Merger-related costs, excluded from revenue and EPS									$ 108.1	$ 13.8
Bargain purchase gain									$ 637

Equity Method Investment in A_3

Equity Method Investment in ARO Equity Method Investment In ARO Narrative (Details) $ in Millions	9 Months Ended	12 Months Ended
	Dec. 31, 2019USD ($)	Dec. 31, 2019USD ($)rigs	Dec. 31, 2019USD ($)	Dec. 31, 2019jackup	Dec. 31, 2019rigs	Dec. 31, 2018USD ($)	Oct. 31, 2018rigs
Schedule of Equity Method Investments [Line Items]
Shareholder Notes Receivable, Terms		10 years
Contributions to establish joint venture		$ 25
Number of rigs sold | rigs							2
LONG-TERM NOTES RECEIVABLE FROM ARO			$ 452.9			$ 0
Contract terms on purchased rigs		15 years
Contract re-pricing and renewal		3 years
Number of Rigs Owned by ARO				7	7
Number of jackups leased by ARO	9	9		9
Number of rigs leased In operation | rigs		9
Number of newbuild jackup rigs | jackup				20
Order Period		10 years
Contract Terms For NewBuild Rigs		8 years
Maximum contingent contributions to joint venture			1,250
Minimum renewal contract terms for newbuild rigs		8 years
Accounts receivable			21.8
Accounts payable			0.7
Due from joint ventures			$ 14.2
Interest income	$ 16.8
ARO
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%	50.00%
Notes Receivable | LIBOR
Schedule of Equity Method Investments [Line Items]
Basis spread on variable rate		2.00%

Equity Method Investment in A_4

Equity Method Investment in ARO Equity Method Investment In ARO - Summarized Financial Data (Details) - USD ($) $ in Millions	3 Months Ended				12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Investment Owned, Balance [Abstract]
Equity in earnings of ARO	$ (9.5)	$ (3.7)	$ 0.6	$ 0	$ (12.6)	$ 0	$ 0
Notes Receivable [Abstract]
Notes Receivable, Related Parties	452.9				452.9
October 2027
Notes Receivable [Abstract]
Notes Receivable, Related Parties	275.2				275.2
October 2028
Notes Receivable [Abstract]
Notes Receivable, Related Parties	177.7				177.7
ARO
Related Party Transactions [Abstract]
Lease revenue					58.2
Secondment revenue					49.9
Transition Services revenue					17.3
Total revenue from ARO (1)					125.4
ARO
Equity Method Investment, Summarized Financial Information, Income Statement [Abstract]
Revenues					410.5
Contract drilling (exclusive of depreciation)					280.2
Depreciation					40.3
General and administrative					27.1
Operating income					62.9
Other expense, net					28.6
Provision for income taxes					9.7
Net income					24.6
Equity Method Investment, Summarized Financial Information, Liabilities and Equity [Abstract]
Current assets	407.2				407.2
Non-current assets	874.8				874.8
Total assets	1,282				1,282
Current liabilities	183.2				183.2
Non-current liabilities	1,015.5				1,015.5
Total liabilities	1,198.7				1,198.7
ARO
Equity Method Investment, Summarized Financial Information, Liabilities and Equity [Abstract]
Total assets	623.5				623.5
Total liabilities	0.7				0.7
Maximum exposure to loss	$ 622.8				622.8
Investment Owned, Balance [Abstract]
50% interest in ARO net income					12.3
Amortization of basis differences					(24.9)
Equity in earnings of ARO					$ (12.6)

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Supplemental Executive Retirement Plans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in unrealized gains (losses) included in other income	$ 5,000,000	$ (700,000)	$ 4,500,000

Fair Value Measurements (Schedu

Fair Value Measurements (Schedule Of Financial Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Assets Held-in-trust, Noncurrent	$ 26	$ 27.2
Derivative Asset	5.4
Derivative Liability		(10.7)
Financial Liabilities Fair Value Disclosure		(10.7)
Total financial assets	31.4	27.2
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Assets Held-in-trust, Noncurrent	26	27.2
Derivative Asset	0
Derivative Liability		0
Financial Liabilities Fair Value Disclosure		0
Total financial assets	26	27.2
Significant observable inputs (Level 2)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Assets Held-in-trust, Noncurrent	0	0
Derivative Asset	5.4
Derivative Liability		(10.7)
Financial Liabilities Fair Value Disclosure		(10.7)
Total financial assets	5.4	0
Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Assets Held-in-trust, Noncurrent	0	0
Derivative Asset	0
Derivative Liability		0
Financial Liabilities Fair Value Disclosure		0
Total financial assets	$ 0	$ 0

Fair Value Measurements (Sche_2

Fair Value Measurements (Schedule Of Carrying Values And Estimated Fair Values Of Debt Instruments) (Details) - USD ($) $ in Millions		3 Months Ended			12 Months Ended
		Sep. 30, 2017	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2019	Dec. 31, 2015	Dec. 31, 2018	Mar. 31, 2018	Mar. 31, 2017
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Current maturities of long-term debt					$ 124.8		$ 0
Long-term Debt, Excluding Current Maturities					$ 5,923.5		5,010.4
6.875% Senior notes due 2020
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage					6.875%
Senior Note Maturity Year					2020
6.875% Senior notes due 2020 | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage				6.875%
Senior Note Maturity Year			2020	2020
4.70% Senior notes due 2021
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage					4.70%
Senior Note Maturity Year					2021
4.70% Senior notes due 2021 | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage				4.70%
Senior Note Maturity Year			2021	2021
4.875%SeniorNotesDue2022Member [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage					4.875%
Senior Note Maturity Year					2022
4.875%SeniorNotesDue2022Member [Member] | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage					4.875%
3.00% Exchangeable senior notes due 2024(2)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage					3.00%
Senior Note Maturity Year					2024
3.00% Exchangeable senior notes due 2024(2) | Convertible Debt [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage					8.00%
Senior Note Maturity Year					2024
Carrying value of 2024 convertible notes					$ 838.3		$ 836.3
4.50% Senior notes due 2024(1)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage					4.50%
Senior Note Maturity Year					2024
4.50% Senior notes due 2024(1) | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage				4.50%		4.50%
Senior Note Maturity Year						2024
4.75%SeniorNotesDue2024Member [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage					4.75%
Senior Note Maturity Year					2024
4.75%SeniorNotesDue2024Member [Member] | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage					4.75%
8.00% Senior notes due 2024(1)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage					8.00%
Senior Note Maturity Year					2024
8.00% Senior notes due 2024(1) | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage				8.00%	8.00%		8.00%
Senior Note Maturity Year					2024
5.20% Senior notes due 2025(1)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage					5.20%
Senior Note Maturity Year					2025
5.20% Senior notes due 2025(1) | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage				5.20%	5.20%
Senior Note Maturity Year					2025
7.38%SeniorNotesDue2025 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage					7.375%
Senior Note Maturity Year					2025
7.38%SeniorNotesDue2025 [Member] | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage					7.375%
7.75% Senior notes due 2026
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage					7.75%
Senior Note Maturity Year					2026
7.75% Senior notes due 2026 | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage								7.75%
7.20% Senior notes due 2027
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage					7.20%
Senior Note Maturity Year					2027
7.20% Senior notes due 2027 | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage				7.20%			7.20%
7.875% Senior notes due 2040
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage					7.875%
Senior Note Maturity Year					2040
7.875% Senior notes due 2040 | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage				7.875%
Senior Note Maturity Year				2040
5.40%SeniorNotesDue2042 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage					5.40%
Senior Note Maturity Year					2042
5.40%SeniorNotesDue2042 [Member] | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage					5.40%
5.75% Senior notes due 2044
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage					5.75%
Senior Note Maturity Year					2044
5.75% Senior notes due 2044 | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage						5.75%			5.75%
Senior Note Maturity Year		2044				2044
5.85%SeniorNotesDue2044 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage					5.85%
Senior Note Maturity Year					2044
5.85%SeniorNotesDue2044 [Member] | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, interest rate, stated percentage					5.85%
Reported Value Measurement [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term Debt					$ 6,048.3		$ 5,010.4
Long-term Debt, Excluding Current Maturities					5,923.5		5,010.4
Reported Value Measurement [Member] | 6.875% Senior notes due 2020 | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term Debt					124.8		127.5
Reported Value Measurement [Member] | 4.70% Senior notes due 2021 | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term Debt					113.2		112.7
Reported Value Measurement [Member] | 4.875%SeniorNotesDue2022Member [Member] | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term Debt					599.2		0
Reported Value Measurement [Member] | 3.00% Exchangeable senior notes due 2024(2) | Convertible Debt [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term Debt					699		666.8
Reported Value Measurement [Member] | 4.50% Senior notes due 2024(1) | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term Debt					302		619.8
Reported Value Measurement [Member] | 4.75%SeniorNotesDue2024Member [Member] | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term Debt					276.5		0
Reported Value Measurement [Member] | 8.00% Senior notes due 2024(1) | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term Debt					295.7		337
Reported Value Measurement [Member] | 5.20% Senior notes due 2025(1) | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term Debt					331.7		664.4
Reported Value Measurement [Member] | 7.38%SeniorNotesDue2025 [Member] | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term Debt					329.2		0
Reported Value Measurement [Member] | 7.75% Senior notes due 2026 | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term Debt					987.1		985
Reported Value Measurement [Member] | 7.20% Senior notes due 2027 | Debentures Due 2027
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term Debt					111.7		149.3
Reported Value Measurement [Member] | 7.875% Senior notes due 2040 | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term Debt					373.3		375
Reported Value Measurement [Member] | 5.40%SeniorNotesDue2042 [Member] | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term Debt					262.8		0
Reported Value Measurement [Member] | 5.75% Senior notes due 2044 | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term Debt					973.3		972.9
Reported Value Measurement [Member] | 5.85%SeniorNotesDue2044 [Member] | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term Debt					268.8		0
Estimate of Fair Value Measurement [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, Fair Value Disclosure					3,874.1		3,545.8
Current maturities of long-term debt					0		0
Long-term Debt, Fair Value					3,874.1		3,545.8
Estimate of Fair Value Measurement [Member] | 6.875% Senior notes due 2020 | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, Fair Value Disclosure					117.3		121.6
Estimate of Fair Value Measurement [Member] | 4.70% Senior notes due 2021 | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, Fair Value Disclosure					95.5		101.8
Estimate of Fair Value Measurement [Member] | 4.875%SeniorNotesDue2022Member [Member] | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, Fair Value Disclosure					460.5		0
Estimate of Fair Value Measurement [Member] | 3.00% Exchangeable senior notes due 2024(2) | Convertible Debt [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, Fair Value Disclosure	[1]				607.4		575.5
Estimate of Fair Value Measurement [Member] | 4.50% Senior notes due 2024(1) | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, Fair Value Disclosure					167.2		405.2
Estimate of Fair Value Measurement [Member] | 4.75%SeniorNotesDue2024Member [Member] | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, Fair Value Disclosure					201.4		0
Estimate of Fair Value Measurement [Member] | 8.00% Senior notes due 2024(1) | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, Fair Value Disclosure					181.7		273.7
Estimate of Fair Value Measurement [Member] | 5.20% Senior notes due 2025(1) | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, Fair Value Disclosure					186.7		443.9
Estimate of Fair Value Measurement [Member] | 7.38%SeniorNotesDue2025 [Member] | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, Fair Value Disclosure					218.6		0
Estimate of Fair Value Measurement [Member] | 7.75% Senior notes due 2026 | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, Fair Value Disclosure					575.1		725.5
Estimate of Fair Value Measurement [Member] | 7.20% Senior notes due 2027 | Debentures Due 2027
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, Fair Value Disclosure					70		109.1
Estimate of Fair Value Measurement [Member] | 7.875% Senior notes due 2040 | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, Fair Value Disclosure					153.5		223.2
Estimate of Fair Value Measurement [Member] | 5.40%SeniorNotesDue2042 [Member] | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, Fair Value Disclosure					194.4		0
Estimate of Fair Value Measurement [Member] | 5.75% Senior notes due 2044 | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, Fair Value Disclosure					450		566.3
Estimate of Fair Value Measurement [Member] | 5.85%SeniorNotesDue2044 [Member] | Senior Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt instrument, Fair Value Disclosure					$ 194.8		$ 0
[1]	Our 2024 Convertible Notes were issued with a conversion feature. The 2024 Convertible Notes were separated into their liability and equity components on our consolidated balance sheet. The equity component was initially recorded to additional paid-in capital and as a debt discount that will be amortized to interest expense over the life of the instrument. Excluding the unamortized discount, the carrying value of the 2024 Convertible Notes was $838.3 million and $836.3 million as of December 31, 2019 and 2018 , respectively. See "Note 7 - Debt" for additional information on this issuance.

Property And Equipment (Schedul

Property And Equipment (Schedule Of Property And Equipment) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment	$ 18,393.8	$ 15,517
Drilling rigs and equipment
Property, Plant and Equipment [Line Items]
Property and equipment	17,714	14,542.5
Work in progress
Property, Plant and Equipment [Line Items]
Property and equipment	473.6	779.2
Other
Property, Plant and Equipment [Line Items]
Property and equipment	$ 206.2	$ 195.3

Property And Equipment (Narrati

Property And Equipment (Narrative) (Details)	3 Months Ended									12 Months Ended
	Dec. 31, 2019USD ($)	Sep. 30, 2019USD ($)	Jun. 30, 2019USD ($)	Mar. 31, 2019USD ($)	Dec. 31, 2018USD ($)rigs	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2017rigs	Dec. 31, 2019USD ($)rigs	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross, Period Increase (Decrease)										$ 3,200,000,000
Property and equipment	$ 18,393,800,000				$ 15,517,000,000					18,393,800,000	$ 15,517,000,000
Loss on impairment	13,300,000	$ 88,200,000	$ 2,500,000	$ 0	$ 40,300,000	$ 0	$ 0	$ 0		104,000,000	40,300,000	$ 182,900,000
Jackup Rigs [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	385,000,000									385,000,000
Jackup Rigs [Member]
Property, Plant and Equipment [Line Items]
Number Of Drilling Rigs With Impairment | rigs					1				1
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	473,600,000				$ 779,200,000					473,600,000	779,200,000
Construction in Progress [Member] | Ultra Deepwater Drillships [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	417,400,000				416,800,000					$ 417,400,000	416,800,000
Construction in Progress [Member] | Jackup Rigs [Member]
Property, Plant and Equipment [Line Items]
Property and equipment					$ 352,400,000						$ 352,400,000
Moored Semisubmersible Rigs [Member]
Property, Plant and Equipment [Line Items]
Number Of Drilling Rigs With Impairment | rigs										2
Other Rigs [Member]
Property, Plant and Equipment [Line Items]
Loss on impairment										$ 98,400,000
Maximum
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross, Period Increase (Decrease)										0.22
Rowan Companies [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	$ 2,964,000,000									$ 2,964,000,000

Debt (Schedule Of Long-Term Deb

Debt (Schedule Of Long-Term Debt Instruments) (Details) - USD ($) $ in Millions	3 Months Ended			12 Months Ended
	Sep. 30, 2017	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2019	Dec. 31, 2015	Dec. 31, 2018	Mar. 31, 2018	Mar. 31, 2017
Debt Instrument [Line Items]
Current maturities of long-term debt				$ 124.8		$ 0
Long-term Debt, Excluding Current Maturities				$ 5,923.5		5,010.4
6.875% Senior notes due 2020
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				6.875%
Senior Note Maturity Year				2020
6.875% Senior notes due 2020 | Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			6.875%
Senior Note Maturity Year		2020	2020
4.70% Senior notes due 2021
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				4.70%
Senior Note Maturity Year				2021
4.70% Senior notes due 2021 | Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			4.70%
Senior Note Maturity Year		2021	2021
4.875%SeniorNotesDue2022Member [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				4.875%
Senior Note Maturity Year				2022
4.875%SeniorNotesDue2022Member [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				4.875%
3.00% Exchangeable senior notes due 2024(2)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				3.00%
Senior Note Maturity Year				2024
3.00% Exchangeable senior notes due 2024(2) | Convertible Debt [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				8.00%
Senior Note Maturity Year				2024
Carrying value of 2024 convertible notes				$ 838.3		$ 836.3
4.50% Senior notes due 2024(1)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				4.50%
Senior Note Maturity Year				2024
4.50% Senior notes due 2024(1) | Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			4.50%		4.50%
Senior Note Maturity Year					2024
4.75%SeniorNotesDue2024Member [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				4.75%
Senior Note Maturity Year				2024
4.75%SeniorNotesDue2024Member [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				4.75%
8.00% Senior notes due 2024(1)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				8.00%
Senior Note Maturity Year				2024
8.00% Senior notes due 2024(1) | Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			8.00%	8.00%		8.00%
Senior Note Maturity Year				2024
5.20% Senior notes due 2025(1)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				5.20%
Senior Note Maturity Year				2025
5.20% Senior notes due 2025(1) | Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			5.20%	5.20%
Senior Note Maturity Year				2025
7.38%SeniorNotesDue2025 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.375%
Senior Note Maturity Year				2025
7.38%SeniorNotesDue2025 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.375%
7.75% Senior notes due 2026
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.75%
Senior Note Maturity Year				2026
7.75% Senior notes due 2026 | Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage							7.75%
7.20% Senior notes due 2027
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.20%
Senior Note Maturity Year				2027
7.20% Senior notes due 2027 | Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			7.20%			7.20%
7.875% Senior notes due 2040
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.875%
Senior Note Maturity Year				2040
7.875% Senior notes due 2040 | Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			7.875%
Senior Note Maturity Year			2040
5.40%SeniorNotesDue2042 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				5.40%
Senior Note Maturity Year				2042
5.40%SeniorNotesDue2042 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				5.40%
5.75% Senior notes due 2044
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				5.75%
Senior Note Maturity Year				2044
5.75% Senior notes due 2044 | Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					5.75%			5.75%
Senior Note Maturity Year	2044				2044
5.85%SeniorNotesDue2044 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				5.85%
Senior Note Maturity Year				2044
5.85%SeniorNotesDue2044 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				5.85%
Reported Value Measurement [Member]
Debt Instrument [Line Items]
Long-term Debt				$ 6,048.3		$ 5,010.4
Long-term Debt, Excluding Current Maturities				5,923.5		5,010.4
Reported Value Measurement [Member] | 6.875% Senior notes due 2020 | Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt				124.8		127.5
Reported Value Measurement [Member] | 4.70% Senior notes due 2021 | Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt				113.2		112.7
Reported Value Measurement [Member] | 4.875%SeniorNotesDue2022Member [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt				599.2		0
Reported Value Measurement [Member] | 3.00% Exchangeable senior notes due 2024(2) | Convertible Debt [Member]
Debt Instrument [Line Items]
Long-term Debt				699		666.8
Reported Value Measurement [Member] | 4.50% Senior notes due 2024(1) | Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt				302		619.8
Reported Value Measurement [Member] | 4.75%SeniorNotesDue2024Member [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt				276.5		0
Reported Value Measurement [Member] | 8.00% Senior notes due 2024(1) | Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt				295.7		337
Reported Value Measurement [Member] | 5.20% Senior notes due 2025(1) | Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt				331.7		664.4
Reported Value Measurement [Member] | 7.38%SeniorNotesDue2025 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt				329.2		0
Reported Value Measurement [Member] | 7.75% Senior notes due 2026 | Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt				987.1		985
Reported Value Measurement [Member] | 7.20% Senior notes due 2027 | Debentures Due 2027
Debt Instrument [Line Items]
Long-term Debt				111.7		149.3
Reported Value Measurement [Member] | 7.875% Senior notes due 2040 | Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt				373.3		375
Reported Value Measurement [Member] | 5.40%SeniorNotesDue2042 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt				262.8		0
Reported Value Measurement [Member] | 5.75% Senior notes due 2044 | Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt				973.3		972.9
Reported Value Measurement [Member] | 5.85%SeniorNotesDue2044 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt				$ 268.8		$ 0

Debt (Narrative) (Details)

Debt (Narrative) (Details)	3 Months Ended				12 Months Ended
	Sep. 30, 2017	Mar. 31, 2017USD ($)	Dec. 31, 2013	Dec. 31, 2012USD ($)	Dec. 31, 2019USD ($)$ / shares	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2015USD ($)	Sep. 30, 2019USD ($)	Mar. 31, 2018USD ($)	Feb. 28, 2018USD ($)	Feb. 09, 2018USD ($)	Oct. 31, 2017USD ($)	Jun. 30, 2017USD ($)	Jan. 05, 2017USD ($)	Dec. 31, 2016USD ($)
Debt Instrument [Line Items]
Tender Offer						$ 985,000,000
Debt Instrument, Repurchased Face Amount					$ 951,800,000	721,800,000	$ 194,100,000			$ 595,400,000
Extinguishment of Debt, Gain (Loss), Net of Tax						19,000,000
Debt Instrument, Repurchase Amount					724,100,000	771,200,000	204,500,000
Gain (Loss) on Extinguishment of Debt		$ 6,200,000			194,100,000	(19,000,000)	(2,600,000)
Interest Expense					428,300,000	282,700,000	224,200,000
Capitalized interest					$ 20,900,000	62,600,000	72,500,000
Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage					100.00%
Debentures Due 2027
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage					100.00%
7.38%SeniorNotesDue2025 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					7.375%
Senior Note Maturity Year					2025
5.40%SeniorNotesDue2042 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					5.40%
Senior Note Maturity Year					2042
5.85%SeniorNotesDue2044 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					5.85%
Senior Note Maturity Year					2044
3.00% Exchangeable senior notes due 2024(2)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					3.00%
Senior Note Maturity Year					2024
7.875% Senior Notes Due 2040 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					7.875%
Senior Note Maturity Year					2040
4.875%SeniorNotesDue2022Member [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					4.875%
Senior Note Maturity Year					2022
4.75%SeniorNotesDue2024Member [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					4.75%
Senior Note Maturity Year					2024
7.75% Senior notes due 2026
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					7.75%
Senior Note Maturity Year					2026
5.20% Senior notes due 2025(1)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					5.20%
Senior Note Maturity Year					2025
5.75% Senior notes due 2044
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					5.75%
Senior Note Maturity Year					2044
4.50% Senior notes due 2024(1)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					4.50%
Senior Note Maturity Year					2024
4.70% Senior notes due 2021
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					4.70%
Senior Note Maturity Year					2021
6.875% Senior notes due 2020
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					6.875%
Senior Note Maturity Year					2020
8.50% Senior notes due 2019(1)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					8.50%
Senior Note Maturity Year					2019
7.875% Senior notes due 2040
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					7.875%
Senior Note Maturity Year					2040
7.20% Senior notes due 2027
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					7.20%
Senior Note Maturity Year					2027
8.00% Senior notes due 2024(1)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					8.00%
Senior Note Maturity Year					2024
Open Market Repurchases [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount							194,100,000
Debt Instrument, Repurchase Amount							204,500,000
Revolving Credit Facility [Member] | Five Year Credit Facility Member
Debt Instrument [Line Items]
Current borrowing capacity						1,600,000,000							$ 2,000,000,000
Potential_Additional_Revolver_Capacity					$ 250,000,000
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage					0.75%
Maximum Percent of Debt to Total Capitalization Ratio					60.00%
Line of Credit Facility, Fair Value of Amount Outstanding						0
Debt Covenant, Additional Secured Debt, Value					$ 1,000,000,000
Debt Covenant, Additional Secured Debt, Percent Of Tangible Net Worth					10.00%
Common Stock, Dividends, Per Share, Cash Paid | $ / shares					$ 0.01
Debt Covenant, Aggregate Amount Of Available Cash					$ 200,000,000
Revolving Credit Facility [Member] | Credit Facility due 2020 [Member]
Debt Instrument [Line Items]
Current borrowing capacity					1,200,000,000								$ 1,300,000,000
Revolving Credit Facility [Member] | Credit Facility due 2019 [Member]
Debt Instrument [Line Items]
Current borrowing capacity					$ 1,600,000,000
Debt Covenant, Period For Repayment Of Acquired Companies					90 days
Debt Covenant, Aggregate Amount Of Available Cash, After Repayments					$ 250,000,000
Revolving Credit Facility [Member] | Base Rate [Member] | Five Year Credit Facility Member
Debt Instrument [Line Items]
Basis spread on variable rate					3.25%
Revolving Credit Facility [Member] | London Interbank Offered Rate (LIBOR) [Member] | Five Year Credit Facility Member
Debt Instrument [Line Items]
Basis spread on variable rate					4.25%
Convertible Debt [Member] | 3.00% Exchangeable senior notes due 2024(2)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					8.00%
Debt Instrument, Face Amount					$ 849,500,000	849,500,000										$ 849,500,000
Senior Note Maturity Year					2024
Conversion rate per $1,000 principal amount of shares					17.8336
Debt Instrument, Convertible, Conversion Price | $ / shares					$ 56.08
Interest Expense, Debt, Excluding Amortization					$ 25,500,000
Amortization of Debt Issuance Costs and Discounts					$ 32,500,000	31,000,000	31,400,000
Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount							311,200,000									1,093,100,000
Senior Notes [Member] | 7.38%SeniorNotesDue2025 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					7.375%
Debt Instrument, Face Amount					$ 500,000,000
Debt Instrument, Repurchased Face Amount					139,200,000
Debt Instrument, Repurchase Amount					$ 109,200,000
Senior Notes [Member] | 5.40%SeniorNotesDue2042 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					5.40%
Debt Instrument, Face Amount					$ 400,000,000
Senior Notes [Member] | 5.85%SeniorNotesDue2044 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					5.85%
Debt Instrument, Face Amount					$ 400,000,000
Senior Notes [Member] | 7.875% Senior Notes Due 2040 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					7.875%
Debt Instrument, Face Amount					$ 201,400,000
Senior Notes [Member] | 4.875%SeniorNotesDue2022Member [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					4.875%
Debt Instrument, Face Amount					$ 620,800,000
Senior Notes [Member] | 4.75%SeniorNotesDue2024Member [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage					4.75%
Debt Instrument, Face Amount					$ 398,100,000
Debt Instrument, Repurchased Face Amount					79,500,000
Debt Instrument, Repurchase Amount					$ 61,200,000
Senior Notes [Member] | 7.75% Senior notes due 2026
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage										7.75%
Debt Issuance Costs, Gross										$ (16,500,000)
Debt Instrument, Face Amount						1,000,000,000			$ 1,000,000,000
Senior Notes [Member] | 5.20% Senior notes due 2025(1)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				5.20%	5.20%
Debt Instrument, Face Amount																700,000,000
Senior Note Maturity Year					2025
Debt Instrument, Unamortized Discount (Premium), Net		$ 2,600,000
Debt Instrument, Repurchased Face Amount					$ 335,500,000											30,700,000
Debt Instrument, Repurchase Amount					250,000,000
Senior Notes [Member] | 5.75% Senior notes due 2044
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		5.75%						5.75%
Debt Instrument, Face Amount		$ 400,000,000						$ 625,000,000
Senior Note Maturity Year	2044							2044
Debt Instrument, Unamortized Discount (Premium), Net		$ 18,700,000						$ 2,800,000
Debt Instrument, Repurchased Face Amount																24,500,000
Senior Notes [Member] | 4.50% Senior notes due 2024(1)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				4.50%				4.50%
Debt Instrument, Face Amount								$ 625,000,000
Senior Note Maturity Year								2024
Debt Instrument, Unamortized Discount (Premium), Net								$ 900,000
Debt Instrument, Repurchased Face Amount					320,000,000											1,700,000
Debt Instrument, Repurchase Amount					$ 240,000,000
Senior Notes [Member] | 4.70% Senior notes due 2021
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				4.70%
Debt Instrument, Face Amount				$ 1,500,000,000
Senior Note Maturity Year			2021	2021
Debt Instrument, Unamortized Discount (Premium), Net				$ 29,600,000
Debt Instrument, Repurchased Face Amount						$ 156,200,000	413,300,000			156,200,000				$ 39,400,000		817,000,000
Debt Instrument, Repurchase Amount										159,700,000				39,300,000
Senior Notes [Member] | 6.875% Senior notes due 2020
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				6.875%
Debt Instrument, Face Amount				$ 900,000,000
Senior Note Maturity Year			2020	2020
Debt Instrument, Repurchased Face Amount							$ 229,900,000			71,400,000	$ 328,000,000			100,100,000		219,200,000
Debt Instrument, Repurchase Amount											$ 354,700,000			105,100,000
Senior Notes [Member] | 8.50% Senior notes due 2019(1)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				8.50%
Debt Instrument, Face Amount				$ 500,000,000
Senior Note Maturity Year				2019	2019
Debt Instrument, Repurchased Face Amount										$ 55,000,000		$ 237,600,000		54,600,000
Debt Instrument, Repurchase Amount												$ 256,800,000		$ 60,100,000
Senior Notes [Member] | 7.875% Senior notes due 2040
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.875%
Debt Instrument, Face Amount				$ 300,000,000												$ 300,000,000
Senior Note Maturity Year				2040
Senior Notes [Member] | 7.20% Senior notes due 2027
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				7.20%		7.20%
Debt Instrument, Face Amount						$ 150,000,000
Debt Instrument, Repurchased Face Amount					$ 37,900,000
Debt Instrument, Repurchase Amount					$ 29,900,000
Senior Notes [Member] | 8.00% Senior notes due 2024(1)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage				8.00%	8.00%	8.00%
Debt Instrument, Face Amount					$ 332,000,000
Senior Note Maturity Year					2024
Debt Instrument, Repurchased Face Amount					$ 39,700,000
Debt Instrument, Repurchase Amount					$ 33,800,000
Exchange Offers [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount															$ 649,500,000
Debt Instrument, Repurchase Amount															664,500,000
Exchange Offers [Member] | Senior Notes [Member] | 4.70% Senior notes due 2021
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount															373,900,000
Debt Instrument, Repurchase Amount															362,500,000
Exchange Offers [Member] | Senior Notes [Member] | 6.875% Senior notes due 2020
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount															129,800,000
Debt Instrument, Repurchase Amount															138,700,000
Exchange Offers [Member] | Senior Notes [Member] | 8.50% Senior notes due 2019(1)
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount															145,800,000
Debt Instrument, Repurchase Amount															163,300,000
Exchange Offers [Member] | Senior Notes [Member] | 8.00% Senior notes due 2024(1)
Debt Instrument [Line Items]
Debt Instrument, Face Amount															$ 332,000,000

Debt (Schedule of Convertible D

Debt (Schedule of Convertible Debt) (Details) - Convertible Debt [Member] - 3.00% Exchangeable senior notes due 2024(2) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Interest Expense, Debt, Excluding Amortization	$ 25.5
Amortization of Debt Issuance Costs and Discounts	32.5	$ 31	$ 31.4
Debt Instrument, Face Amount	849.5	849.5		$ 849.5
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	(150.5)	(182.7)
Convertible Debt	699	666.8
Debt Instrument, Convertible, Carrying Amount of Equity Component	$ 220	$ 220

Debt (Schedule of Extinguishmen

Debt (Schedule of Extinguishment of Debt - Tender and OMR) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Feb. 28, 2018	Feb. 09, 2018	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2016
Extinguishment of Debt [Line Items]
Debt Instrument, Repurchased Face Amount	$ 951.8	$ 721.8	$ 595.4			$ 194.1
Debt Instrument, Repurchase Amount	724.1	771.2				204.5
Senior Notes [Member]
Extinguishment of Debt [Line Items]
Debt Instrument, Repurchased Face Amount						311.2		$ 1,093.1
Senior Notes [Member] | 4.50% Senior notes due 2024(1)
Extinguishment of Debt [Line Items]
Debt Instrument, Repurchased Face Amount	320							1.7
Debt Instrument, Repurchase Amount	240
Senior Notes [Member] | 4.75%SeniorNotesDue2024Member [Member]
Extinguishment of Debt [Line Items]
Debt Instrument, Repurchased Face Amount	79.5
Debt Instrument, Repurchase Amount	61.2
Senior Notes [Member] | 8.00% Senior notes due 2024(1)
Extinguishment of Debt [Line Items]
Debt Instrument, Repurchased Face Amount	39.7
Debt Instrument, Repurchase Amount	33.8
Senior Notes [Member] | 5.20% Senior notes due 2025(1)
Extinguishment of Debt [Line Items]
Debt Instrument, Repurchased Face Amount	335.5							30.7
Debt Instrument, Repurchase Amount	250
Senior Notes [Member] | 7.38%SeniorNotesDue2025 [Member]
Extinguishment of Debt [Line Items]
Debt Instrument, Repurchased Face Amount	139.2
Debt Instrument, Repurchase Amount	109.2
Senior Notes [Member] | 7.20% Senior notes due 2027
Extinguishment of Debt [Line Items]
Debt Instrument, Repurchased Face Amount	37.9
Debt Instrument, Repurchase Amount	$ 29.9
Senior Notes [Member] | 8.50% Senior notes due 2019(1)
Extinguishment of Debt [Line Items]
Debt Instrument, Repurchased Face Amount			55		$ 237.6		$ 54.6
Debt Instrument, Repurchase Amount					$ 256.8		60.1
Senior Notes [Member] | 6.875% Senior notes due 2020
Extinguishment of Debt [Line Items]
Debt Instrument, Repurchased Face Amount			71.4	$ 328		229.9	100.1	219.2
Debt Instrument, Repurchase Amount				$ 354.7			105.1
Senior Notes [Member] | 4.70% Senior notes due 2021
Extinguishment of Debt [Line Items]
Debt Instrument, Repurchased Face Amount		$ 156.2	156.2			$ 413.3	39.4	$ 817
Debt Instrument, Repurchase Amount			$ 159.7				$ 39.3

Debt (Schedule of Extinguishm_2

Debt (Schedule of Extinguishment of Debt - Exchange Offers) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Feb. 28, 2018	Feb. 09, 2018	Dec. 31, 2017	Jun. 30, 2017	Jan. 05, 2017	Dec. 31, 2016	Dec. 31, 2012
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount	$ 951.8	$ 721.8	$ 595.4			$ 194.1
Debt Instrument, Repurchase Amount	724.1	771.2				204.5
Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount						311.2			$ 1,093.1
Senior Notes [Member] | 8.50% Senior notes due 2019(1)
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount			55		$ 237.6		$ 54.6
Debt Instrument, Face Amount										$ 500
Debt Instrument, Repurchase Amount					$ 256.8		60.1
Senior Notes [Member] | 6.875% Senior notes due 2020
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount			71.4	$ 328		229.9	100.1		219.2
Debt Instrument, Face Amount										900
Debt Instrument, Repurchase Amount				$ 354.7			105.1
Senior Notes [Member] | 4.70% Senior notes due 2021
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount		$ 156.2	156.2			$ 413.3	39.4		$ 817
Debt Instrument, Face Amount										$ 1,500
Debt Instrument, Repurchase Amount			$ 159.7				$ 39.3
Senior Notes [Member] | 8.00% Senior notes due 2024(1)
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount	39.7
Debt Instrument, Face Amount	332
Debt Instrument, Repurchase Amount	$ 33.8
Exchange Offers [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchased Amount Paid in Cash								$ 332.5
Exchange Offers [Member] | 8.50% Senior notes due 2019(1)
Debt Instrument [Line Items]
Debt Instrument, Repurchased Amount Paid in Cash								81.7
Exchange Offers [Member] | 6.875% Senior notes due 2020
Debt Instrument [Line Items]
Debt Instrument, Repurchased Amount Paid in Cash								69.4
Exchange Offers [Member] | 4.70% Senior notes due 2021
Debt Instrument [Line Items]
Debt Instrument, Repurchased Amount Paid in Cash								181.4
Exchange Offers [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount								649.5
Debt Instrument, Repurchase Amount								664.5
Exchange Offers [Member] | Senior Notes [Member] | 8.50% Senior notes due 2019(1)
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount								145.8
Debt Instrument, Repurchase Amount								163.3
Exchange Offers [Member] | Senior Notes [Member] | 8.50% senior notes due 2019 exchanged for 8.00% senior notes due 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount								81.6
Exchange Offers [Member] | Senior Notes [Member] | 6.875% Senior notes due 2020
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount								129.8
Debt Instrument, Repurchase Amount								138.7
Exchange Offers [Member] | Senior Notes [Member] | 6.875% Senior notes due 2020 exchanged for 8.00% Senior notes due 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount								69.3
Exchange Offers [Member] | Senior Notes [Member] | 4.70% Senior notes due 2021
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount								373.9
Debt Instrument, Repurchase Amount								362.5
Exchange Offers [Member] | Senior Notes [Member] | 4.70% senior notes due 2021 exchanged for 8.00% senior notes due 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount								181.1
Exchange Offers [Member] | Senior Notes [Member] | 8.00% Senior notes due 2024(1)
Debt Instrument [Line Items]
Debt Instrument, Face Amount								$ 332

(Aggregate Maturities Of Long-T

(Aggregate Maturities Of Long-Term Debt) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Sep. 30, 2019	Dec. 31, 2018	Mar. 31, 2018	Feb. 28, 2018	Dec. 31, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2012
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount	$ (951.8)		$ (721.8)	$ (595.4)		$ (194.1)
Long-Term Debt, Gross	6,528.1								$ 6,049.5
Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount						(311.2)			(1,093.1)
Debt Instrument, Repurchased Face Amount Net of Debt Issuance	1,367.1		515.8
Senior Notes [Member] | 6.875% Senior notes due 2020
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount				(71.4)	$ (328)	(229.9)	$ (100.1)		(219.2)
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	122.9
Face (Par) Amount of the Original Debt Instrument, Including Repurchases and Equity Exchanges									900
Debt Instrument, Face Amount											$ 900
Senior Notes [Member] | 4.70% Senior notes due 2021
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount			(156.2)	$ (156.2)		(413.3)	$ (39.4)		(817)
Long-term Debt, Maturities, Repayments of Principal in Year Two	113.5
Face (Par) Amount of the Original Debt Instrument, Including Repurchases and Equity Exchanges									1,500
Debt Instrument, Face Amount											1,500
Senior Notes [Member] | 4.875%SeniorNotesDue2022Member [Member]
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Year Three	620.8
Debt Instrument, Face Amount	620.8
Senior Notes [Member] | 4.50% Senior notes due 2024(1)
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount	(320)								(1.7)
Long-term Debt, Maturities, Repayments of Principal in Year Five	303.3
Face (Par) Amount of the Original Debt Instrument, Including Repurchases and Equity Exchanges									625
Debt Instrument, Face Amount										$ 625
Senior Notes [Member] | 4.75%SeniorNotesDue2024Member [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount	(79.5)
Long-Term Debt, Maturities, Repayments of Principal after Year Five	318.6
Debt Instrument, Face Amount	398.1
Senior Notes [Member] | 8.00% Senior notes due 2024(1)
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount	(39.7)
Long-Term Debt, Maturities, Repayments of Principal after Year Five	292.3
Face (Par) Amount of the Original Debt Instrument, Including Repurchases and Equity Exchanges						$ 332
Debt Instrument, Face Amount	332
Senior Notes [Member] | 5.20% Senior notes due 2025(1)
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount	(335.5)								(30.7)
Long-Term Debt, Maturities, Repayments of Principal after Year Five	333.8
Face (Par) Amount of the Original Debt Instrument, Including Repurchases and Equity Exchanges									700
Debt Instrument, Face Amount									700
Senior Notes [Member] | 7.38%SeniorNotesDue2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount	(139.2)
Long-Term Debt, Maturities, Repayments of Principal after Year Five	360.8
Debt Instrument, Face Amount	500
Senior Notes [Member] | 7.75% Senior notes due 2026
Debt Instrument [Line Items]
Long-Term Debt, Maturities, Repayments of Principal after Year Five	1,000
Debt Instrument, Face Amount		$ 1,000	1,000
Senior Notes [Member] | 7.20% Senior notes due 2027
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount	(37.9)
Long-Term Debt, Maturities, Repayments of Principal after Year Five	112.1
Face (Par) Amount of the Original Debt Instrument, Including Repurchases and Equity Exchanges									150
Debt Instrument, Face Amount			150
Senior Notes [Member] | 7.875% Senior notes due 2040
Debt Instrument [Line Items]
Long-Term Debt, Maturities, Repayments of Principal after Year Five	300
Debt Instrument, Face Amount									300		$ 300
Senior Notes [Member] | 5.40%SeniorNotesDue2042 [Member]
Debt Instrument [Line Items]
Long-Term Debt, Maturities, Repayments of Principal after Year Five	400
Debt Instrument, Face Amount	400
Senior Notes [Member] | 5.75% Senior notes due 2044
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount									(24.5)
Long-Term Debt, Maturities, Repayments of Principal after Year Five	1,000.5
Face (Par) Amount of the Original Debt Instrument, Including Repurchases and Equity Exchanges									1,025
Debt Instrument, Face Amount								$ 400		$ 625
Senior Notes [Member] | 5.85%SeniorNotesDue2044 [Member]
Debt Instrument [Line Items]
Long-Term Debt, Maturities, Repayments of Principal after Year Five	400
Debt Instrument, Face Amount	400
Convertible Debt [Member] | 3.00% Exchangeable senior notes due 2024(2)
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Year Four	849.5
Debt Instrument, Face Amount	$ 849.5		$ 849.5						$ 849.5

Derivative Instruments (Narrati

Derivative Instruments (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	$ 5.4	$ (10.7)
Maximum maturity period for all derivatives	18 months
Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net gains on derivatives not designated as hedging instruments	$ (6.4)	$ (11.8)	$ 10
Foreign Exchange Forward [Member] | Cash Flow Hedges [Member] | Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	199.1
Foreign Exchange Forward [Member] | Fair Value Hedging [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	47.1
United Kingdom, Pounds | Foreign Exchange Forward [Member] | Cash Flow Hedges [Member] | Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	114.8
United Kingdom, Pounds | Foreign Exchange Forward [Member] | Fair Value Hedging [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	15.4
Israel, New Shekels | Foreign Exchange Forward [Member] | Fair Value Hedging [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	6.6
Nigeria, Nairas | Foreign Exchange Forward [Member] | Fair Value Hedging [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	4.9
Thailand, Baht | Foreign Exchange Forward [Member] | Fair Value Hedging [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	4.5
Australia, Dollars | Foreign Exchange Forward [Member] | Cash Flow Hedges [Member] | Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	45.9
Australia, Dollars | Foreign Exchange Forward [Member] | Fair Value Hedging [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	4.3
Norway, Krone | Foreign Exchange Forward [Member] | Cash Flow Hedges [Member] | Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	10.9
Norway, Krone | Foreign Exchange Forward [Member] | Fair Value Hedging [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	5.9
Euro Member Countries, Euro | Foreign Exchange Forward [Member] | Cash Flow Hedges [Member] | Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	15.9
Brazil, Brazil Real | Foreign Exchange Forward [Member] | Cash Flow Hedges [Member] | Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	3.7
Singapore, Dollars | Foreign Exchange Forward [Member] | Cash Flow Hedges [Member] | Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	7.9
No currency | Foreign Exchange Forward [Member] | Fair Value Hedging [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	$ 5.5

Derivative Instruments (Schedul

Derivative Instruments (Schedule Of Derivatives At Fair Value) (Details) - USD ($) $ in Millions		Dec. 31, 2019	Dec. 31, 2018
Derivative [Line Items]
Total fair value of derivative assets		$ 6.3	$ 0.6
Total fair value of derivative liabilities		0.9	11.3
Designated as Hedging Instrument [Member]
Derivative [Line Items]
Total fair value of derivative assets		5	0.2
Total fair value of derivative liabilities		0.7	8.7
Designated as Hedging Instrument [Member] | Foreign Exchange Forward [Member] | Other Noncurrent Assets [Member]
Derivative [Line Items]
Total fair value of derivative assets		0.8	0
Designated as Hedging Instrument [Member] | Foreign Exchange Forward [Member] | Other Current Assets [Member]
Derivative [Line Items]
Total fair value of derivative assets	[1]	4.2	0.2
Designated as Hedging Instrument [Member] | Foreign Exchange Forward [Member] | Other Current Liabilities [Member]
Derivative [Line Items]
Total fair value of derivative liabilities	[1]	0.7	8.3
Designated as Hedging Instrument [Member] | Foreign Exchange Forward [Member] | Other Noncurrent Liabilities [Member]
Derivative [Line Items]
Total fair value of derivative liabilities		0	0.4
Not Designated as Hedging Instrument [Member] | Foreign Exchange Forward [Member] | Other Current Assets [Member]
Derivative [Line Items]
Total fair value of derivative assets	[1]	1.3	0.4
Not Designated as Hedging Instrument [Member] | Foreign Exchange Forward [Member] | Other Current Liabilities [Member]
Derivative [Line Items]
Total fair value of derivative liabilities	[1]	$ 0.2	$ 2.6
[1]	Derivative assets and liabilities that have maturity dates equal to or less than 12 months from the respective balance sheet dates were included in other current assets and accrued liabilities and other, respectively, on our consolidated balance sheets.

Derivative Instruments (Gains A

Derivative Instruments (Gains And Losses On Derivatives Designated As Cash Flow Hedges) (Details) - USD ($)		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Interest Rate Lock Contracts [Member]
Derivative [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	[1]	$ 0	$ 0	$ 0
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	[1],[2]	1,900,000	200,000	200,000
Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion and Amount Excluded from Effectiveness Testing)	[1],[3]	0	0	0
Foreign Currency Forward Contracts [Member]
Derivative [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	[4]	1,600,000	(9,700,000)	8,500,000
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	[2],[4]	6,400,000	(1,200,000)	200,000
Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion and Amount Excluded from Effectiveness Testing)	[3],[4]	0	(1,900,000)	(700,000)
Cash Flow Hedges [Member]
Derivative [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net		1,600,000	9,700,000	(8,500,000)
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)		8,300,000	(1,000,000)	400,000
Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion and Amount Excluded from Effectiveness Testing)		0	(1,900,000)	(700,000)
Contract Drilling [Member] | Foreign Currency Forward Contracts [Member]
Derivative [Line Items]
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)		(7,300,000)	400,000	(1,100,000)
Depreciation Expense [Member] | Foreign Currency Forward Contracts [Member]
Derivative [Line Items]
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)		$ 900,000	$ 800,000	$ 900,000
[1]	Losses on interest rate lock derivatives reclassified from AOCI into income were included in interest expense, net, in our consolidated statements of operations.
[2]	Changes in the fair value of cash flow hedges are recorded in AOCI. Amounts recorded in AOCI associated with cash flow hedges are subsequently reclassified into contract drilling, depreciation or interest expense as earnings are affected by the underlying hedged forecasted transaction.
[3]	Gains and losses recognized in income for amounts excluded from effectiveness testing were included in other, net, in our consolidated statements of operations. As a result of our adoption of Update 2017-12 on January 1, 2019, ineffectiveness is no longer separately measured and recognized.
[4]	During the year ended December 31, 2019 , $7.3 million of losses were reclassified from AOCI into contract drilling expense and $0.9 million of gains were reclassified from AOCI into depreciation expense in our consolidated statement of operations. During the year ended December 31, 2018 , $400,000 of gains were reclassified from AOCI into contract drilling expense and $800,000 of gains were reclassified from AOCI into depreciation expense in our consolidated statement of operations. During the year ended December 31, 2017 , $1.1 million of losses were reclassified from AOCI into contract drilling expense and $900,000 of gains were reclassified from AOCI into depreciation expense in our consolidated statement of operations.

Derivative Instruments (Sched_2

Derivative Instruments (Schedule Of Estimated Amount Of Net Gains Associated With Derivatives) (Details) $ in Millions	Dec. 31, 2019USD ($)
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Net unrealized gains to be reclassified to contract drilling expense	$ 3.4
Net realized gains to be reclassified to depreciation expense	0.8
Net gains to be reclassified to earnings	$ 4.2

Shareholders' Equity (Schedule

Shareholders' Equity (Schedule Of Activity In Our Various Shareholders' Equity) (Details) - USD ($) shares in Millions, $ in Millions	Oct. 05, 2017	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Increase (Decrease) in Stockholders' Equity [Roll Forward]
BALANCE					$ 8,088.8							$ 8,088.8
Net loss		$ (214)	$ (197.5)	$ 407.3	$ (188)	$ (203.1)	$ (142.9)	$ (150.1)	$ (140.5)			(192.2)	$ (636.6)	$ (304.2)
Increase (Decrease) in Obligation, Pension and Other Postretirement Benefits												(21.7)	0	0
Net other comprehensive income (loss)												(12)	(11.2)	$ 9.6
BALANCE		$ 9,309.6				$ 8,088.8						$ 9,309.6	$ 8,088.8
Common Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
BALANCE, shares					115.2				111.8		77.6	115.2	111.8	77.6
BALANCE					$ 46.2				$ 44.8		$ 31.1	$ 46.2	$ 44.8	$ 31.1
Stock Issued During Period, Value, New Issues													$ 13.2
Shares Issued Under Share Based Compensation Plans, Shares										1.1		2.7	3.4
Shares issued under share-based compensation plans, net										$ 0.5		$ 1.1	$ 1.4
BALANCE, shares		205.9				115.2				111.8		205.9	115.2	111.8
BALANCE		$ 82.5				$ 46.2				$ 44.8		$ 82.5	$ 46.2	$ 44.8
Additional Paid-In Capital [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
BALANCE					7,225				7,195		6,402.2	7,225	7,195	6,402.2
Shares issued under share-based compensation plans, net										(0.4)		(1.3)	(0.6)
Share-based compensation cost											35.7	37.2	30.6
Payments of Stock Issuance Costs		(0.6)
BALANCE		8,627.8				7,225				7,195		8,627.8	7,225	7,195
Retained Earnings [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
BALANCE					874.2				1,532.7		1,864.1	874.2	1,532.7	1,864.1
Net loss											(303.7)	(198)	(639.7)
Cash dividends paid											(13.6)	(4.5)	(18)
BALANCE		671.7				874.2				1,532.7		671.7	874.2	1,532.7
AOCI [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
BALANCE					18.2				28.6		19	18.2	28.6	19
Increase (Decrease) in Obligation, Pension and Other Postretirement Benefits												(21.7)
Net other comprehensive income (loss)											9.6	9.7	(11.2)
BALANCE		6.2				18.2				28.6		6.2	18.2	28.6
Treasury Shares [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
BALANCE					(72.2)				(69)		(65.8)	(72.2)	(69)	(65.8)
Shares issued under share-based compensation plans, net										(1.3)		(0.7)	(1.3)
Repurchase of shares											(1.9)	(4.5)	(1.9)
BALANCE		(77.3)				(72.2)				(69)		(77.3)	(72.2)	(69)
Noncontrolling Interest [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
BALANCE					$ (2.6)				$ (2.1)		4.4	(2.6)	(2.1)	4.4
Net loss											(0.5)	5.8	3.1
Distributions to noncontrolling interests											$ (6)	(4.5)	(3.6)
BALANCE		$ (1.3)				$ (2.6)				$ (2.1)		(1.3)	(2.6)	(2.1)
Accounting Standards Update 2016-16 [Member] | Retained Earnings [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification														$ 14.1
New Accounting Pronouncement, Early Adoption, Effect [Member] | Retained Earnings [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification													(0.8)
New Accounting Pronouncement, Early Adoption, Effect [Member] | AOCI [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification													0.8
Atwood Oceanics, Inc. | Common Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued During Period, Shares, New Issues	33.1
Atwood Oceanics, Inc. | Additional Paid-In Capital [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued During Period, Value, New Issues													757.5
Rowan Companies [Member] | Common Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued During Period, Shares, New Issues				88
Stock Issued During Period, Value, New Issues												$ 35.2
Rowan Companies [Member] | Additional Paid-In Capital [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued During Period, Value, New Issues													1,367.5
Rowan Companies [Member] | Treasury Shares [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued During Period, Value, New Issues													$ 0.1

Shareholders' Equity (Share Iss

Shareholders' Equity (Share Issuance Narrative) (Details) - USD ($)	Apr. 11, 2019	Oct. 06, 2017	Oct. 05, 2017	Jun. 30, 2019	Dec. 31, 2019
Shares Issuance [Line Items]
Stock Repurchase Program, Authorized Amount					$ 500,000,000
Stock Repurchase Program, Number of Shares Authorized to be Repurchased					16,300,000
Stock Repurchased During Period, Shares					0
Rowan Companies [Member]
Shares Issuance [Line Items]
Business Combination, Consideration Transferred	$ 1,400,000,000				$ 1,402,800,000
Atwood Oceanics, Inc.
Shares Issuance [Line Items]
Business Combination, Consideration Transferred		$ 770,700,000
Class A Ordinary Shares, U.S. [Member] | Rowan Companies [Member]
Shares Issuance [Line Items]
Number of ordinary shares	88,300,000
Shares Issued, Price Per Share	$ 15.88
Class A Ordinary Shares, U.S. [Member] | Atwood Oceanics, Inc.
Shares Issuance [Line Items]
Shares Issued, Price Per Share			$ 5.83
Maximum
Shares Issuance [Line Items]
Common Stock, Shares Authorized					67,600,000
Maximum | Private Placement [Member]
Shares Issuance [Line Items]
Common Stock, Shares Authorized					135,300,000
Common Stock [Member] | Rowan Companies [Member]
Shares Issuance [Line Items]
Stock Issued During Period, Shares, New Issues				88,000,000
Common Stock [Member] | Atwood Oceanics, Inc.
Shares Issuance [Line Items]
Stock Issued During Period, Shares, New Issues			33,100,000

Benefit Plans (Narrative) (Deta

Benefit Plans (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employer contributions	$ 12,800
Long-Term Incentive Plan (LTIP) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares Authorized	14,800,000	14,800,000
Shares reserved for issuance as awards	2,500,000	2,500,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Granted in Period		4,500,000
Share Options Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost on awards	$ 0	$ 0
Share options award, outstanding	375,701	375,701
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	$ 52.77	$ 52.77
Share Appreciation Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share options award, outstanding	530,923	530,923
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	$ 50.70	$ 50.70
Non-Vested Share Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost on awards	$ 115,900	$ 115,900
Recognized compensation cost, weighted-average period, years		1 year 8 months 12 days
Non-Vested Share Awards [Member] | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share awards, vest rate		33.00%
Non-Vested Share Awards [Member] | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share awards, vest rate		20.00%
Exercisable In Increments Over Three-Year Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share awards, vest rate		33.00%
Exercisable In Increments Over Four-Year Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share awards, vest rate		25.00%
Performance Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost on awards	800	$ 800
Recognized compensation cost, weighted-average period, years		1 year 1 month 6 days
Share option awards, exercisable, increment		3 years
Performance awards, granted, aggregate grant-date fair value	$ 6,700	$ 6,700
Performance awards, vested, aggregate fair value		2,200	$ 700	$ 2,900
Recognized compensation expense		$ 3,200	8,200	8,400
Savings Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance as awards	1,000,000	1,000,000
Employee match		100.00%
Employer contributions		$ 18,700	$ 14,400	$ 12,200
Savings Plan [Member] | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum percentage of eligible employee compensation to be matched by employer		5.00%
Atwood Oceanics, Inc. | Long-Term Incentive Plan (LTIP) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance as awards	100,000	100,000
Rowan Companies [Member] | Long-Term Incentive Plan (LTIP) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance as awards	2,300,000	2,300,000

Benefit Plans (Summary Of Non-V

Benefit Plans (Summary Of Non-Vested Share Award Related Compensation Expense Recognized) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Tax benefit	$ (2.5)	$ (2.8)	$ (4.8)
Total non-vested share award related compensation expense included in net income	37	30.6	28
Contract Drilling [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Non-vested share award related compensation expense	22.1	18.9	18.3
General And Administrative [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Non-vested share award related compensation expense	17.4	14.5	14.5
Operating Expenses [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Non-vested share award related compensation expense	$ 39.5	$ 33.4	$ 32.8

Benefit Plans (Summary Of Value

Benefit Plans (Summary Of Value Of Non-Vested Share Awards Granted And Vested) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Non Vested Share Awards, Equity Classified [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant-date fair value of non-vested share awards granted (per share)	$ 11,500,000	$ 24.62	$ 31.48
Total fair value of non-vested share awards vested during the period (in millions)	$ 17.7	$ 7.5	$ 8.2
Non-Vested Share Awards, Liability Classified [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant-date fair value of non-vested share awards granted (per share)	$ 0	$ 21.35	$ 25.08
Total fair value of non-vested share awards vested during the period (in millions)	$ 3.5	$ 9.9	$ 3.9

Benefit Plans (Summary Of Non_2

Benefit Plans (Summary Of Non-Vested Share Award Activity) (Details) - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Non Vested Share Awards, Equity Classified [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Share awards and cash-settled awards as of December 31, 2018	2,017,000
Non-vested Granted, Shares	4,460,000
Non-vested Assumed, Shares	2,329,000
Non-vested Vested, Shares	(1,519,000)
Non-vested Forfeited, Shares	(854,000)
Share awards and cash-settled awards as of December 31, 2019	6,433,000	2,017,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Non-vested as of December 31, 2018, Weighted-Average Grant-Date Fair Value	$ 31.36
Non-vested Granted, Weighted-Average Grant-Date Fair Value	11,500,000	$ 24.62	$ 31.48
Non-vested Assumed, Weighted-Average Grant-Date Fair Value	15,880,000
Non-vested Vested, Weighted-Average Grant-Date Fair Value	10,530,000
Non-vested Forfeited, Weighted-Average Grant-Date Fair Value	8,870,000
Non-vested as of December 31, 2019, Weighted-Average Grant-Date Fair Value	$ 19,890,000	$ 31.36
Non-Vested Share Awards, Liability Classified [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Share awards and cash-settled awards as of December 31, 2018	1,279,000
Non-vested Granted, Shares	0
Non-vested Vested, Shares	(453,000)
Non-vested Forfeited, Shares	(129,000)
Share awards and cash-settled awards as of December 31, 2019	697,000	1,279,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Non-vested as of December 31, 2018, Weighted-Average Grant-Date Fair Value	$ 29.20
Non-vested Granted, Weighted-Average Grant-Date Fair Value	0	$ 21.35	$ 25.08
Non-vested Vested, Weighted-Average Grant-Date Fair Value	7,970,000
Non-vested Forfeited, Weighted-Average Grant-Date Fair Value	11,580,000
Non-vested as of December 31, 2019, Weighted-Average Grant-Date Fair Value	$ 46,280,000	$ 29.20

Pension and Other Postretiremen

Pension and Other Postretirement Benefits Pension Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Apr. 11, 2019
Defined Benefit Plan Disclosure [Line Items]
Net benefit liabilities	$ 249.6	$ 239.3
Net projected benefit obligations, current	$ 2.9	19.2
Expected return on plan assets	6.48%
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Net benefit liabilities	$ 233.5	$ 202.1
Net projected benefit obligations, current	1.4
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	35.7
Other Postretirement Benefits Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	$ 1.5

Pension and Other Post-retire_3

Pension and Other Post-retirement Benefits Changes in Benefit Obligations and Plan Assets (Details) - USD ($) $ in Millions	9 Months Ended
	Dec. 31, 2019	Dec. 31, 2019	Apr. 11, 2019	Dec. 31, 2018
Projected benefit obligation:
Balance, April 11		$ 816
Interest cost		21.7
Service cost		1.5
Actuarial loss		44
Benefits paid		(34.5)
Foreign currency adjustments		(0.2)
Balance, December 31	$ 848.5	848.5
Plan assets
Fair value, April 11		576.8
Actual return		43.6
Employer contributions		12.8
Benefits paid		(34.1)
Foreign currency adjustments		0.2
Fair value, December 31	598.9	598.9
Amounts recognized in consolidated balance sheet:
Accrued liabilities	(2.9)	(2.9)	$ (19.2)
Other liabilities (long-term)	(246.7)	(246.7)		$ 0
Net benefit liabilities	(249.6)	(249.6)	(239.3)
Accumulated contributions in excess of (less than) net periodic benefit cost	(222.1)	(222.1)
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax [Abstract]
Actuarial loss	(27.5)	(27.5)
Total accumulated other comprehensive loss	(27.5)	(27.5)
Pension Benefits
Projected benefit obligation:
Balance, April 11		800.1
Interest cost	21.3	21.3
Service cost	1.5	1.5
Actuarial loss		43.8
Benefits paid		(34.1)
Foreign currency adjustments		(0.2)
Balance, December 31	832.4	832.4
Plan assets
Fair value, April 11		576.8
Actual return		43.6
Employer contributions		12.8
Benefits paid		(34.1)
Foreign currency adjustments		0.2
Fair value, December 31	598.9	598.9
Amounts recognized in consolidated balance sheet:
Accrued liabilities	(1.4)	(1.4)
Other liabilities (long-term)	(232.1)	(232.1)
Net benefit liabilities	(233.5)	(233.5)	$ (202.1)
Accumulated contributions in excess of (less than) net periodic benefit cost	(206.2)	(206.2)
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax [Abstract]
Actuarial loss	(27.3)	(27.3)
Total accumulated other comprehensive loss	$ (27.3)	$ (27.3)
Weighted-average assumptions:
Discount rate	3.16%	3.16%
Rate of compensation increase	0.00%	0.00%
Other Benefits
Projected benefit obligation:
Balance, April 11		$ 15.9
Interest cost		0.4
Service cost		0
Actuarial loss		0.2
Benefits paid		(0.4)
Foreign currency adjustments		0
Balance, December 31	$ 16.1	16.1
Plan assets
Fair value, April 11		0
Actual return		0
Employer contributions		0
Benefits paid		0
Foreign currency adjustments		0
Fair value, December 31	0	0
Amounts recognized in consolidated balance sheet:
Accrued liabilities	(1.5)	(1.5)
Other liabilities (long-term)	(14.6)	(14.6)
Net benefit liabilities	(16.1)	(16.1)
Accumulated contributions in excess of (less than) net periodic benefit cost	(15.9)	(15.9)
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax [Abstract]
Actuarial loss	(0.2)	(0.2)
Total accumulated other comprehensive loss	$ (0.2)	$ (0.2)
Weighted-average assumptions:
Discount rate	3.06%	3.06%
Rate of compensation increase	0.00%	0.00%

Pension and Other Post-retire_4

Pension and Other Post-retirement Benefits Accumulated Benefit Obligations (Details) $ in Millions	Dec. 31, 2019USD ($)
Asset Retirement Obligation Disclosure [Abstract]
Defined Benefit Plan, Accumulated Benefit Obligation	$ 844.3

Pension and Other Post-retire_5

Pension and Other Post-retirement Benefits Net Periodic Pension Costs and Weighted Average Assumptions (Details) - USD ($) $ in Millions	9 Months Ended
	Dec. 31, 2019	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Service cost		$ 1.5
Interest cost		21.7
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1.5	1.5
Interest cost	21.3	$ 21.3
Expected return on plan assets	(27.1)
Net periodic pension costs	$ (4.3)
Discount rate	3.82%

Pension and Other Post-retire_6

Pension and Other Post-retirement Benefits Schedule of Allocation of Plan Assets (Details) - USD ($) $ in Millions	Dec. 31, 2019	Apr. 11, 2019
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	$ 598.9	$ 576.8
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	598.9	$ 576.8
Pension Benefits | Total
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	598.9
Pension Benefits | Quoted prices in active markets for identical assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	84.1
Pension Benefits | Significant observable inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	$ 514.8
Pension Benefits | Equities: | Minimum
Defined Benefit Plan Disclosure [Line Items]
Target range	53.00%
Pension Benefits | Equities: | Maximum
Defined Benefit Plan Disclosure [Line Items]
Target range	69.00%
Pension Benefits | U.S. large cap | Minimum
Defined Benefit Plan Disclosure [Line Items]
Target range	22.00%
Pension Benefits | U.S. large cap | Maximum
Defined Benefit Plan Disclosure [Line Items]
Target range	28.00%
Pension Benefits | U.S. large cap | Total
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	$ 148.9
Pension Benefits | U.S. large cap | Quoted prices in active markets for identical assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	0
Pension Benefits | U.S. large cap | Significant observable inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	$ 148.9
Pension Benefits | U.S. small cap | Minimum
Defined Benefit Plan Disclosure [Line Items]
Target range	4.00%
Pension Benefits | U.S. small cap | Maximum
Defined Benefit Plan Disclosure [Line Items]
Target range	10.00%
Pension Benefits | U.S. small cap | Total
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	$ 41.1
Pension Benefits | U.S. small cap | Quoted prices in active markets for identical assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	0
Pension Benefits | U.S. small cap | Significant observable inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	$ 41.1
Pension Benefits | International all cap | Minimum
Defined Benefit Plan Disclosure [Line Items]
Target range	21.00%
Pension Benefits | International all cap | Maximum
Defined Benefit Plan Disclosure [Line Items]
Target range	29.00%
Pension Benefits | International all cap | Total
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	$ 152.4
Pension Benefits | International all cap | Quoted prices in active markets for identical assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	0
Pension Benefits | International all cap | Significant observable inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	$ 152.4
Pension Benefits | International small cap | Minimum
Defined Benefit Plan Disclosure [Line Items]
Target range	2.00%
Pension Benefits | International small cap | Maximum
Defined Benefit Plan Disclosure [Line Items]
Target range	8.00%
Pension Benefits | International small cap | Total
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	$ 34.7
Pension Benefits | International small cap | Quoted prices in active markets for identical assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	0
Pension Benefits | International small cap | Significant observable inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	$ 34.7
Pension Benefits | Real estate equities | Minimum
Defined Benefit Plan Disclosure [Line Items]
Target range	0.00%
Pension Benefits | Real estate equities | Maximum
Defined Benefit Plan Disclosure [Line Items]
Target range	13.00%
Pension Benefits | Real estate equities | Total
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	$ 54.9
Pension Benefits | Real estate equities | Quoted prices in active markets for identical assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	0
Pension Benefits | Real estate equities | Significant observable inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	$ 54.9
Pension Benefits | Fixed income: | Minimum
Defined Benefit Plan Disclosure [Line Items]
Target range	25.00%
Pension Benefits | Fixed income: | Maximum
Defined Benefit Plan Disclosure [Line Items]
Target range	35.00%
Pension Benefits | Cash and equivalents | Minimum
Defined Benefit Plan Disclosure [Line Items]
Target range	0.00%
Pension Benefits | Cash and equivalents | Maximum
Defined Benefit Plan Disclosure [Line Items]
Target range	10.00%
Pension Benefits | Cash and equivalents | Total
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	$ 6.5
Pension Benefits | Cash and equivalents | Quoted prices in active markets for identical assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	6.5
Pension Benefits | Cash and equivalents | Significant observable inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	$ 0
Pension Benefits | Aggregate | Minimum
Defined Benefit Plan Disclosure [Line Items]
Target range	9.00%
Pension Benefits | Aggregate | Maximum
Defined Benefit Plan Disclosure [Line Items]
Target range	19.00%
Pension Benefits | Aggregate | Total
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	$ 76.7
Pension Benefits | Aggregate | Quoted prices in active markets for identical assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	0
Pension Benefits | Aggregate | Significant observable inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	$ 76.7
Pension Benefits | Core plus | Minimum
Defined Benefit Plan Disclosure [Line Items]
Target range	9.00%
Pension Benefits | Core plus | Maximum
Defined Benefit Plan Disclosure [Line Items]
Target range	19.00%
Pension Benefits | Core plus | Total
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	$ 77.6
Pension Benefits | Core plus | Quoted prices in active markets for identical assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	77.6
Pension Benefits | Core plus | Significant observable inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	0
Pension Benefits | Group annuity contracts | Total
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	6.1
Pension Benefits | Group annuity contracts | Quoted prices in active markets for identical assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	0
Pension Benefits | Group annuity contracts | Significant observable inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Assets	$ 6.1

Pension and Other Post-retire_7

Pension and Other Post-retirement Benefits Estimated Future Annual Benefit Payments From Plan Assets (Details) $ in Millions	Dec. 31, 2019USD ($)
Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2020	$ 45
2021	45
2022	44.6
2023	44.2
2024	43.9
2025 through 2029	213.6
Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2020	1.5
2021	1.4
2022	1.3
2023	1.3
2024	1.3
2025 through 2029	$ 5.3

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) $ in Thousands, € in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2019USD ($)	Sep. 30, 2019USD ($)	Dec. 31, 2019EUR (€)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Mar. 31, 2020USD ($)
Investments, Owned, Federal Income Tax Note [Line Items]
Tax Cuts and Jobs Act, Measurement Period Adjustment, Income Tax Expense (Benefit)				$ 13,800	$ 11,700	$ 16,500
Effective Income Tax Rate Reconciliation, Tax Credit, Foreign, Amount				46,000
Income from continuing operations before income taxes in the U.S. countries				39,000	(115,100)	6,300
Income from continuing operations before income taxes in the non-U.S. countries				102,800	423,800	(202,300)
Tax Cuts and Jobs Act, Incomplete Accounting, Provisional Income Tax Expense (Benefit)				16,500
Deferred tax assets related to U.S. foreign tax credits	$ 142,900			142,900	123,600
Deferred tax assets related to net operating loss carryforwards	1,546,700			1,546,700	148,400
Net operating loss carryforwards	6,400,000			6,400,000
Operating Loss Carryforwards, Limitations on Use	41,500			41,500
Operating loss carryforwards, Not subject to expiration	5,600,000			5,600,000
Operating loss carryforwards, Subject to expiration	773,000			773,000
Valuation allowance on NOL carryforwards and FTC	1,500,000			1,500,000
Income Tax Expense (Benefit), Discrete Item				2,300		32,200
Effective Income Tax Rate Reconciliation, Debt and Settlement Proceeds				28,300
Other discrete income tax expenses				$ 26,000	$ 21,000	$ 15,700
Consilidated effective income tax rate excluding discrete items			(14.60%)	(14.60%)	(24.80%)	(96.00%)
Deferred Tax Assets, Gross	2,814,700			$ 2,814,700	$ 376,200
Minimum percentage threshold for recognition of tax benefits			50.00%	50.00%
Total unrecognized tax benefits	296,700			$ 296,700	143,000	$ 147,600
Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions With Net Operating Loss Carryforwards				32,500	6,500
Amount of unrecognized tax benefits affecting the consolidated effective income tax rate if recognized	253,900			253,900
Amount of accrued interest and penalties included in other liabilities	58,900			58,900	40,500
Amount of interest and penalties recognized in net tax expense				5,700	1,900	4,400
Income tax benefits, inclusive of interest and penalties due to lapses in statute of limitations	5,300			5,300	5,300	1,100
Decline in unrecognized tax benefits during next twelve months	800			800
Accrued interest and penalty assessments related to the decline in unrecognized tax benefits	550			550
Tax Assessment		$ 42,000
Aggregate Undistributed Earnings of Subsidiaries to be Continually Reinvested	289,000			289,000
Deferred Tax Asset, Restructuring Transactions	998,000			998,000
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Foreign Income Tax On Domestic Subsidiaries, Provisional Income Tax Expense (Benefit)						38,500
Tax Cuts and Jobs Act, Incomplete Accounting, Transition Tax for Accumulated Foreign Earnings, Provisional Income Tax Expense						17,300
Tax Cuts and Jobs Act of 2017, Change in Tax Rate, Deferred Tax Liability, Income Tax (Expense) Benefit						20,000
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Change in Tax Rate, Valuation Allowance, Provisional Income Tax Benefit						$ 19,300
Rowan Companies [Member]
Investments, Owned, Federal Income Tax Note [Line Items]
Net operating loss carryforwards	1,300,000			$ 1,300,000
Minimum
Investments, Owned, Federal Income Tax Note [Line Items]
Deferred Tax Assets, Foreign, Expiration Date			2022	2022
Operating loss carryforwards tax credits expiration year			2020	2020
Maximum
Investments, Owned, Federal Income Tax Note [Line Items]
Deferred Tax Assets, Foreign, Expiration Date			2029	2029
Operating loss carryforwards tax credits expiration year			2037	2037
Other Liabilities [Member]
Investments, Owned, Federal Income Tax Note [Line Items]
Total unrecognized tax benefits	264,200			$ 264,200	$ 136,500
Australian Taxation Office [Member] | Rowan Companies [Member]
Investments, Owned, Federal Income Tax Note [Line Items]
Unrecognized tax benefit, maximum exposure	70,900	$ 29,000
Tax Assessment Liability	15,000			15,000
Tax Assessment	101,000
Luxembourg Inland Revenue [Member] | Rowan Companies [Member]
Investments, Owned, Federal Income Tax Note [Line Items]
Unrecognized tax benefit, maximum exposure			€ 142	159,000
Tax Assessment Liability	$ 104,000			$ 104,000
Tax Assessment | €			€ 93
Forecast [Member] | Minimum
Investments, Owned, Federal Income Tax Note [Line Items]
Deferred Tax Assets, Gross							$ 40,000
Forecast [Member] | Maximum
Investments, Owned, Federal Income Tax Note [Line Items]
Deferred Tax Assets, Gross							$ 60,000

Income Taxes (Summary Of Compon

Income Taxes (Summary Of Components Of Provision For Income Taxes From Continuing Operations) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Components of Income Tax Expense (Benefit), Continuing Operations [Abstract]
Current income tax expense, U.S.									$ 31.3	$ (19.9)	$ (2.2)
Current income tax expense, Non-U.S.									73.2	52.9	56.4
Current Income Tax Expense, Total									104.5	33	54.2
Deferred income tax expense (benefit), U.S.									19.7	52.9	36
Deferred income tax expense (benefit), Non-U.S.									4.2	3.7	19
Deferred income tax expense									23.9	56.6	55
Total provision for income taxes	$ 62.8	$ 1.5	$ 32.6	$ 31.5	$ 23.2	$ 23.3	$ 24.7	$ 18.4	$ 128.4	$ 89.6	$ 109.2

Income Taxes (Summary Of Signif

Income Taxes (Summary Of Significant Components Of Deferred Income Tax Assets (Liabilities)) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Net operating loss carryforwards	$ 1,546.7	$ 148.4
Deferred Tax Assets, Capital Loss Carryforwards	998	0
Foreign tax credits	142.9	123.6
Interest limitation carryforwards	41.5	40.2
Premiums on long-term debt	0	23.8
Employee benefits, including share-based compensation	73.9	15.4
Deferred revenue	0.1	10.3
Other	11.6	14.5
Total deferred tax assets	2,814.7	376.2
Valuation allowance	(2,588.7)	(316)
Net deferred tax assets	226	60.2
Property and equipment	(156)	(54.5)
Net discounts on long-term debt	(49.5)	0
Deferred U.S. tax on foreign income	(36.7)	(31.5)
Other	(23.7)	(9)
Total deferred tax liabilities	265.9	95
Total deferred tax liabilities	$ (39.9)	$ (34.8)

Income Taxes (Summary Of Effect

Income Taxes (Summary Of Effective Income Tax Rate On Continuing Operations) (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Components of Income Tax Expense (Benefit), Continuing Operations [Abstract]
U.K. statutory income tax rate	19.00%	19.00%	19.20%
Non-U.K. taxes	(280.90%)	(18.00%)	(40.40%)
Bargain purchase gain	189.70%	(0.20%)	13.80%
Valuation allowance	(145.10%)	(16.90%)	(18.00%)
Debt repurchases	48.70%	(1.60%)	(2.80%)
Asset impairments	(31.00%)	(1.40%)	(17.10%)
U.S. tax reform	(21.60%)	2.20%	(8.40%)
Restructuring transaction	7.90%	1.70%	0.00%
Other	12.00%	(1.40%)	(2.00%)
Effective income tax rate	(201.30%)	(16.60%)	(55.70%)

Income Taxes (Summary Of Reconc

Income Taxes (Summary Of Reconciliation Of The Beginning And Ending Amount Of Unrecognized Tax Benefits) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Components of Income Tax Expense (Benefit), Continuing Operations [Abstract]
Balance, beginning of year	$ 143	$ 147.6
Increases in unrecognized tax benefits as a result of tax positions taken during the current year	17.8	6.5
Impact of foreign currency exchange rates	(0.3)	(5)
Lapse of applicable statutes of limitations	(4.4)	(4.5)
Increases in unrecognized tax benefits as a result of tax positions taken during prior years	1.1	2.5
Decreases in unrecognized tax benefits as a result of tax positions taken during prior years	(2.4)	(3.8)
Settlements with taxing authorities	(8)	(0.3)
Increases in unrecognized tax benefits as a result of Atwood acquisition	149.9	0
Balance, end of year	$ 296.7	$ 143

Commitments And Contingencies_2

Commitments And Contingencies (Capital Commitments) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Aggregate Contractual Capital Commitments Due In One Year		$ 0
Aggregate Contractual Capital Commitments Due In Two Years		83.9
Aggregate Contractual Capital Commitments Due In Three Years		165
Aggregate Contractual Capital Commitments Due Thereafter		0
Total		248.9
Holding Costs		23
Milestone Payment		313.3
ENSCO DS-13 [Member]
Property, Plant and Equipment [Line Items]
Aggregate Contractual Capital Commitments Due In One Year		0
Aggregate Contractual Capital Commitments Due In Two Years		83.9
Aggregate Contractual Capital Commitments Due In Three Years		0
Aggregate Contractual Capital Commitments Due Thereafter		0
Total		83.9
ENSCO DS-14 [Member]
Property, Plant and Equipment [Line Items]
Aggregate Contractual Capital Commitments Due In Two Years		0
Aggregate Contractual Capital Commitments Due In Three Years		165
Aggregate Contractual Capital Commitments Due Thereafter		0
Total		$ 165
Forecast [Member]
Property, Plant and Equipment [Line Items]
Projected Capital Expenditures	$ 160

Commitments And Contingencies_3

Commitments And Contingencies (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		12 Months Ended
	Aug. 31, 2018	Mar. 31, 2020	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Gain Contingencies [Line Items]
Loss Contingency, Damages Sought, Value	$ 10			$ 180
Proceeds from Legal Settlements				200	$ 0	$ 0
Gain (Loss) Related to Litigation Settlement			$ 20.3
Letters of Credit Outstanding, Amount			$ 99.5	$ 99.5
Forecast [Member]
Gain Contingencies [Line Items]
Proceeds from Legal Settlements		$ 27.5

Leases Lease Narrative (Details

Leases Lease Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Leased Assets [Line Items]
Operating Lease, Right-of-Use Asset	$ 58.1	$ 0
Cash paid for lease liabilities	29.9
Impairment of Leasehold	5.6
Operating Lease, Liability, Current	21.1	0
Operating Lease, Liability, Noncurrent	$ 51.8	0
Operating Leases, Rent Expense		$ 40.1	$ 37
Minimum
Operating Leased Assets [Line Items]
Remaining lease terms	1 year
Maximum
Operating Leased Assets [Line Items]
Remaining lease terms	10 years
Rowan Companies [Member]
Operating Leased Assets [Line Items]
Operating Lease, Right-of-Use Asset	$ 12.2
Operating Lease, Liability, Current	3.9
Operating Lease, Liability, Noncurrent	$ 10.6

Leases Lease Components of Leas

Leases Lease Components of Lease Expense (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019USD ($)
Leases [Abstract]
Long-term operating lease cost	$ 29.5
Short-term operating lease cost	12.2
Sublease income	2.4
Lease, Cost	$ 39.3

Leases Leases Supplemental Bala

Leases Leases Supplemental Balance Sheet Information (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Leases [Abstract]
Operating Lease, Right-of-Use Asset	$ 58.1	$ 0
Current lease liability	21.1	0
Long-term lease liability	51.8	$ 0
Total operating lease liabilities	$ 72.9
Weighted-average remaining lease term (in years)	5 years 1 month 6 days
Operating Lease, Weighted Average Discount Rate, Percent	8.23%

Leases Leases Maturities of Lea

Leases Leases Maturities of Lease Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Leases [Abstract]
Operating Leases, Future Minimum Payments, Due in Three Years		$ 11.9
2020	$ 25.4
2021	18.4
2022	12.6
2023	10.7
2024	8.1
Thereafter	17.2
Total lease payments	92.4
Less imputed interest	19.5
Total operating lease liabilities	$ 72.9

Leases Future Minimum Rental Pa

Leases Future Minimum Rental Payments (Details) $ in Millions	Dec. 31, 2018USD ($)
Leases [Abstract]
Operating Leases, Future Minimum Payments Due, Next Twelve Months	$ 32.3
Operating Leases, Future Minimum Payments, Due in Two Years	18.7
Operating Leases, Future Minimum Payments, Due in Four Years	9.2
Operating Leases, Future Minimum Payments, Due in Five Years	8.9
Operating Leases, Future Minimum Payments, Due Thereafter	15.2
Operating Leases, Future Minimum Payments Due	96.2
Operating Leases, Future Minimum Payments, Due in Three Years	$ 11.9

Segment Information (Narrative)

Segment Information (Narrative) (Details) - 12 months ended Dec. 31, 2019	rigssegments	jackup	contract
Segment Reporting Information [Line Items]
Number of operating segments | segments	3
Number of contract drilling rigs	74
Number of jackups leased by ARO	9	9
Number of drilling management contracts | contract			2
Floaters [Member] | Ultra Deepwater Drillships [Member]
Segment Reporting Information [Line Items]
Number of contract drilling rigs	16
Floaters [Member] | Dynamically Positioned Semisubmersible [Member]
Segment Reporting Information [Line Items]
Number of contract drilling rigs	8
Floaters [Member] | Moored Semisubmersible Rigs [Member]
Segment Reporting Information [Line Items]
Number of contract drilling rigs	2
Floaters [Member] | Asset under Construction [Member]
Segment Reporting Information [Line Items]
Number of contract drilling rigs	2
Jackups [Member]
Segment Reporting Information [Line Items]
Number of jackups leased by ARO | jackup		9
Rigs Held for Sale | jackup		3
Jackups [Member] | Jackup Rigs Deployed [Member]
Segment Reporting Information [Line Items]
Number of contract drilling rigs	41

Segment Information (Schedule O

Segment Information (Schedule Of Segment Reporting Information) (Details) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019USD ($)contract	Sep. 30, 2019USD ($)	Jun. 30, 2019USD ($)	Mar. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2019USD ($)contract	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)
Segment Reporting Information [Line Items]
Number of drilling management contracts | contract	2								2
Revenues	$ 512.1	$ 551.3	$ 583.9	$ 405.9	$ 399	$ 430.9	$ 458.5	$ 417	$ 2,053.2	$ 1,705.4	$ 1,843
Operating expenses - Contract drilling (exclusive of depreciation)									1,806	1,319.4	1,189.5
Loss on impairment	13.3	88.2	2.5	0	40.3	0	0	0	104	40.3	182.9
Depreciation expense	163.8	163	157.9	125	122.4	120.6	120.7	115.2	609.7	478.9	444.8
General and administrative	42	36.1	81.2	29.6	23.6	25.1	26.1	27.9	188.9	102.7	157.8
Income (Loss) from Equity Method Investments	9.5	3.7	(0.6)	0					12.6	0	0
OPERATING LOSS	(193.1)	$ (236.2)	$ (157.4)	$ (81.3)	(110.1)	$ (41.9)	$ (32.6)	$ (51.3)	(668)	(235.9)	(132)
Property and equipment, net	15,096.9				12,616.2				15,096.9	12,616.2	12,873.7
Capital expenditures									227	426.7	536.7
Floaters [Member]
Segment Reporting Information [Line Items]
OPERATING LOSS										(35.7)	47.2
Floaters [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues									1,014.4	1,013.5	1,143.5
Operating expenses - Contract drilling (exclusive of depreciation)									898.6	737.4	624.2
Loss on impairment									88.2	0	174.7
Depreciation expense									378.6	311.8	297.4
General and administrative									0	0	0
Income (Loss) from Equity Method Investments									0
OPERATING LOSS									(351)
Property and equipment, net	10,073.1				9,465.6				10,073.1	9,465.6	9,650.9
Capital expenditures									31.4	105.5	470.3
Jackups [Member]
Segment Reporting Information [Line Items]
OPERATING LOSS										(89.2)	(11.5)
Jackups [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues									834.6	630.9	640.3
Operating expenses - Contract drilling (exclusive of depreciation)									788.9	526.5	512.1
Loss on impairment									10.2	40.3	8.2
Depreciation expense									212.4	153.3	131.5
General and administrative									0	0	0
Income (Loss) from Equity Method Investments									0
OPERATING LOSS									(176.9)
Property and equipment, net	4,322.7				3,114.1				4,322.7	3,114.1	3,177.6
Capital expenditures									184.6	317.7	62.1
ARO | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues									410.5	0	0
Operating expenses - Contract drilling (exclusive of depreciation)									280.2	0	0
Loss on impairment									0	0	0
Depreciation expense									40.3	0	0
General and administrative									27.1	0	0
Income (Loss) from Equity Method Investments									0
OPERATING LOSS									62.9	0	0
Property and equipment, net	650.7				0				650.7	0	0
Capital expenditures									27.5	0	0
Other [Member]
Segment Reporting Information [Line Items]
OPERATING LOSS										5.5	6
Other [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues									204.2	61	59.2
Operating expenses - Contract drilling (exclusive of depreciation)									118.5	55.5	53.2
Loss on impairment									0	0	0
Depreciation expense									0	0	0
General and administrative									0	0	0
Income (Loss) from Equity Method Investments									0
OPERATING LOSS									85.7
Property and equipment, net	701.1				0				701.1	0	0
Capital expenditures									0	0	0
Reconciling Items [Member] | Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Revenues									(410.5)	0	0
Operating expenses - Contract drilling (exclusive of depreciation)									(280.2)	0	0
Loss on impairment									5.6	0	0
Depreciation expense									(21.6)	13.8	15.9
General and administrative									161.8	102.7	157.8
Income (Loss) from Equity Method Investments									12.6
OPERATING LOSS									(288.7)	(116.5)	(173.7)
Property and equipment, net	$ (650.7)				$ 36.5				(650.7)	36.5	45.2
Capital expenditures									$ (16.5)	$ 3.5	$ 4.3

Segment Information (Schedule_2

Segment Information (Schedule Of Geographic Distribution Of Rigs By Segment) (Details)	Dec. 31, 2019rigs
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	79
Held-for-sale
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	3
Floaters [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	27
Floaters [Member] | Held-for-sale
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	1
Jackups [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	43
Jackups [Member] | Held-for-sale
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	2
Other [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	9
Other [Member] | Held-for-sale
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	0
ARO
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	7
ARO | Held-for-sale
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	0
North & South America (Excluding Brazil) [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	18
North & South America (Excluding Brazil) [Member] | Floaters [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	10
North & South America (Excluding Brazil) [Member] | Jackups [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	8
North & South America (Excluding Brazil) [Member] | Other [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	0
North & South America (Excluding Brazil) [Member] | ARO
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	0
Europe & Mediterranean [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	21
Europe & Mediterranean [Member] | Floaters [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	7
Europe & Mediterranean [Member] | Jackups [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	14
Europe & Mediterranean [Member] | Other [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	0
Europe & Mediterranean [Member] | ARO
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	0
Middle East & Africa [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	25
Middle East & Africa [Member] | Floaters [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	4
Middle East & Africa [Member] | Jackups [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	12
Middle East & Africa [Member] | Other [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	9
Middle East & Africa [Member] | ARO
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	7
Asia Pacific [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	10
Asia Pacific [Member] | Construction in Progress [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	2
Asia Pacific [Member] | Floaters [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	3
Asia Pacific [Member] | Floaters [Member] | Construction in Progress [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	2
Asia Pacific [Member] | Jackups [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	7
Asia Pacific [Member] | Jackups [Member] | Construction in Progress [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	0
Asia Pacific [Member] | Other [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	0
Asia Pacific [Member] | Other [Member] | Construction in Progress [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	0
Asia Pacific [Member] | ARO
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	0
Asia Pacific [Member] | ARO | Construction in Progress [Member]
Segment Reporting Information [Line Items]
Total number of contract drilling rigs	0

Segment Information (Schedule_3

Segment Information (Schedule Of Long-Lived Assets By Geographical Segment) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Long-lived Assets	$ 15,096.9	$ 12,616.2	$ 12,873.7
Geographic Areas [Member]
Segment Reporting Information [Line Items]
Long-lived Assets	15,096.9	12,616.2	12,873.7
Geographic Areas [Member] | United States [Member]
Segment Reporting Information [Line Items]
Long-lived Assets	2,943.9	2,270	2,764.9
Geographic Areas [Member] | SAUDI ARABIA
Segment Reporting Information [Line Items]
Long-lived Assets	1,257.7	668.6	93.6
Geographic Areas [Member] | United Kingdom [Member]
Segment Reporting Information [Line Items]
Long-lived Assets	1,204	1,185.2	609.4
Geographic Areas [Member] | SPAIN
Segment Reporting Information [Line Items]
Long-lived Assets	3,012.4	2,306.6	2,004.2
Geographic Areas [Member] | NIGERIA
Segment Reporting Information [Line Items]
Long-lived Assets	787.3	1,368.2	583.3
Geographic Areas [Member] | SINGAPORE
Segment Reporting Information [Line Items]
Long-lived Assets	22.6	23.9	2,859.3
Geographic Areas [Member] | Other countries [Member]
Segment Reporting Information [Line Items]
Long-lived Assets	$ 5,869	$ 4,793.7	$ 3,959

Supplemental Financial Inform_3

Supplemental Financial Information (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Supplemental Financial Information [Abstract]
Capitalized interest	$ 20.9	$ 62.6	$ 72.5
Capital expenditure accruals	$ 16.3	$ 27.8	$ 243.3

Supplemental Financial Inform_4

Supplemental Financial Information (Accounts Receivable, Net) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Supplemental Information For Property, Casualty Insurance Underwriters [Line Items]
Accounts receivable	$ 526.7	$ 348.1
Allowance for doubtful accounts	(6)	(3.4)
Accounts receivable, net	520.7	344.7
Trade [Member]
Supplemental Information For Property, Casualty Insurance Underwriters [Line Items]
Accounts receivable	466.4	301.7
Other Credit Derivatives [Member]
Supplemental Information For Property, Casualty Insurance Underwriters [Line Items]
Accounts receivable	$ 60.3	$ 46.4

Supplemental Financial Inform_5

Supplemental Financial Information (Other Current Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Supplemental Financial Information [Abstract]
Inventory	$ 340.1	$ 268.1
Prepaid taxes	36.2	35
Deferred mobilization costs	23.3	23.5
Prepaid expenses	13.5	15.2
Other	33.4	19.1
Other current assets	$ 446.5	$ 360.9

Supplemental Financial Inform_6

Supplemental Financial Information (Other Assets, Net) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Supplemental Financial Information [Abstract]
Operating Lease, Right-of-Use Asset	$ 58.1	$ 0
Income Taxes Receivable, Current	36.3	8.4
Deferred tax assets	26.6	29.4
Supplemental executive retirement plan assets	26	27.2
Finite-Lived Intangible Assets, Net	11.9	2.5
Deferred mobilization costs	7.1	13.5
Other	22.3	16.8
Other assets, net	$ 188.3	$ 97.8

Supplemental Financial Inform_7

Supplemental Financial Information (Accrued Liabilities And Other) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Supplemental Financial Information [Abstract]
Personnel costs	$ 134.4	$ 82.5
Accrued interest	115.2	100.6
Taxes	61.2	36.9
Deferred revenue	30	56.9
Operating Lease, Liability, Current	21.1	0
Other	55.8	41.1
Accrued liabilities and other	$ 417.7	$ 318

Supplemental Financial Inform_8

Supplemental Financial Information (Other Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Supplemental Financial Information [Abstract]
Unrecognized tax benefits (inclusive of interest and penalties)	$ 323.1	$ 177
Liability, Defined Benefit Plan, Noncurrent	246.7	0
Deferred Tax Liabilities, Net, Noncurrent	99	70.7
Intangible Liabilities Noncurrent	52.1	53.5
Operating Lease, Liability, Noncurrent	51.8	0
Supplemental executive retirement plan liabilities	26.7	28.1
Personnel costs	24.5	25.1
Deferred revenue	9.7	20.5
Other Accrued Liabilities, Noncurrent	33.8	21.1
Other liabilities	$ 867.4	$ 396

Supplemental Financial Inform_9

Supplemental Financial Information (Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Supplemental Financial Information [Abstract]
Derivative Instruments	$ 22.6	$ 12.6
Increase (Decrease) in Obligation, Pension and Other Postretirement Benefits	(21.7)	0
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax	7.1	7.3
Other	(1.8)	(1.7)
Accumulated other comprehensive income	$ 6.2	$ 18.2

Supplemental Financial Infor_10

Supplemental Financial Information (Repair And Maintenance Expense Related To Continuing Operations) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Supplemental Financial Information [Abstract]
Repair and maintenance expense	$ 303.7	$ 198.4	$ 188.7

Supplemental Financial Infor_11

Supplemental Financial Information Supplemental Financial Information (Other Income) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Supplemental Financial Information [Abstract]
Bargain purchase gain		$ 637	$ 1.8	$ 140.2
Proceeds from Legal Settlements		200	0	0
Gain (Loss) on Extinguishment of Debt	$ 6.2	194.1	(19)	(2.6)
Payments for Legal Settlements		(20.3)	0	0
Net foreign currency exchange gains (losses)		(7.4)	(17.2)	(5.1)
Other Nonoperating Income		1		1.9
Other Nonoperating Expense			(0.4)
Other, net		$ 1,004.4	$ (34.8)	$ 134.4

Supplemental Financial Infor_12

Supplemental Financial Information (Cash Flows Information) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Supplemental Financial Information [Abstract]
(Increase) decrease in accounts receivable	$ 29.5	$ (6.2)	$ 83.2
(Increase) decrease in other assets	(32)	(2.8)	(14)
(Decrease) increase in liabilities	(25.4)	2.7	3.2
Changes in operating assets and liabilities	$ (27.9)	$ (6.3)	$ 72.4

Supplemental Financial Infor_13

Supplemental Financial Information (Cash Paid For Interest And Income Taxes) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Supplemental Financial Information [Abstract]
Interest, net of amounts capitalized	$ 410	$ 232.6	$ 199.8
Income taxes	$ 107.6	$ 58.4	$ 62.8

Supplemental Financial Infor_14

Supplemental Financial Information Supplemental Financial Information (Major Customers) (Details)		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenue from External Customer [Line Items]
Document Period End Date		Dec. 31, 2019
Customer Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Revenue from External Customer [Line Items]
Concentration Risk, Percentage		100.00%	100.00%	100.00%
TOTAL [Member] | Customer Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Revenue from External Customer [Line Items]
Concentration Risk, Percentage	[1]	16.00%	15.00%	22.00%
Saudi Aramco [Member] [Domain] | Customer Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Revenue from External Customer [Line Items]
Concentration Risk, Percentage		7.00%	11.00%	9.00%
Petrobras [Member] | Customer Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Revenue from External Customer [Line Items]
Concentration Risk, Percentage		4.00%	8.00%	11.00%
BP [Member] | Customer Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Revenue from External Customer [Line Items]
Concentration Risk, Percentage	[1]	9.00%	7.00%	15.00%
Other Customers [Member] | Customer Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Revenue from External Customer [Line Items]
Concentration Risk, Percentage		64.00%	59.00%	43.00%
Floaters [Member] | TOTAL [Member] | Customer Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Revenue from External Customer [Line Items]
Concentration Risk, Percentage		93.00%
Floaters [Member] | BP [Member] | Customer Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Revenue from External Customer [Line Items]
Concentration Risk, Percentage		16.00%	27.00%	78.00%
Other Rigs [Member] | BP [Member] | Customer Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Revenue from External Customer [Line Items]
Concentration Risk, Percentage		43.00%	53.00%
Jackups Member | BP [Member] | Customer Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Revenue from External Customer [Line Items]
Concentration Risk, Percentage		41.00%	20.00%
[1]	For the years ended December 31, 2019 , 93% of revenues provided by Total were attributable to the Floaters segment and the remainder was attributable to the Jackup segment. During the years 2018 and 2017

Supplemental Financial Infor_15

Supplemental Financial Information Supplemental Financial Information (Revenue by region) (Details) - USD ($) $ in Millions		3 Months Ended									12 Months Ended
		Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues		$ 512.1	$ 551.3	$ 583.9	$ 405.9	$ 399	$ 430.9	$ 458.5	$ 417		$ 2,053.2	$ 1,705.4	$ 1,843
Geographic Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues											2,053.2	1,705.4	1,843
Angola [Member] | Geographic Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	[1]										$ 284	$ 285.7	445.7
Angola [Member] | Floaters [Member] | Geographic Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Segment Reporting, Revenue Reconciling Item [Line Items]
Concentration Risk, Percentage										88.00%	87.00%	86.00%
AUSTRALIA | Geographic Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	[1]										$ 204.2	$ 283.9	206.7
AUSTRALIA | Floaters [Member] | Geographic Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Segment Reporting, Revenue Reconciling Item [Line Items]
Concentration Risk, Percentage										87.00%	90.00%	92.00%
Us Gulf Of Mexico [Member] | Geographic Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	[2]										$ 301	$ 214.7	$ 149.8
Us Gulf Of Mexico [Member] | Floaters [Member] | Geographic Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Segment Reporting, Revenue Reconciling Item [Line Items]
Concentration Risk, Percentage											46.00%	30.00%	29.00%
Us Gulf Of Mexico [Member] | Jackups Member | Geographic Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Segment Reporting, Revenue Reconciling Item [Line Items]
Concentration Risk, Percentage											28.00%	42.00%	31.00%
United Kingdom [Member] | Geographic Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	[3]										$ 213.1	$ 192.6	$ 164.6
SAUDI ARABIA | Geographic Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	[1]										$ 313.4	182.2	171.8
SAUDI ARABIA | Jackups Member | Geographic Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Segment Reporting, Revenue Reconciling Item [Line Items]
Concentration Risk, Percentage											65.00%
SAUDI ARABIA | Other [Member] | Geographic Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Segment Reporting, Revenue Reconciling Item [Line Items]
Concentration Risk, Percentage											35.00%
Brazil [Member] | Geographic Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	[4]										$ 117.8	139.6	196.2
EGYPT | Geographic Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	[4]										40.4	31.2	214.8
Other Geographic Areas [Member] | Geographic Concentration Risk [Member] | Sales Revenue, Services, Net [Member] (Deprecated 2019-01-31)
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues											$ 579.3	$ 375.5	$ 293.4
[1]	For the years ended December 31, 2019 , 65% and 35% of revenues were attributable to our Jackup and Other segments, respectively. For the years ended December 31, 2018 and 2017 , all revenues earned were attributable to our Jackup segment.
[2]	For the years ended December 31, 2019, 2018 and 2017 , 46% , 30% and 29% of revenues earned in the U.S. Gulf of Mexico, respectively, were attributable to our Floaters segment, 28% , 42% and 31% of revenues were attributable to our Jackup segment, respectively, and the remaining revenues were attributable to our Other segment, respectively.
[3]	For the years ended December 31, 2019, 2018 and 2017 , all revenues earned in the United Kingdom were attributable to our Jackup segment.
[4]	For the years ended December 31, 2019, 2018 and 2017 , 87% , 86% and 88% of revenues earned in Angola, respectively, were attributable to our Floaters segment with the remaining revenues attributable to our Jackup segment.

Guarantee Of Registered Secur_3

Guarantee Of Registered Securities (Narrative) (Details)	12 Months Ended
	Dec. 31, 2019USD ($)
Guarantor Obligations [Line Items]
Senior notes aggregate outstanding principal balance	$ 422,900,000
6.875% Senior notes due 2020
Guarantor Obligations [Line Items]
Senior Note Maturity Year	2020
Debt instrument interest rate stated percentage	6.875%
7.875% Senior Notes Due 2040 [Member]
Guarantor Obligations [Line Items]
Senior Note Maturity Year	2040
Debt instrument interest rate stated percentage	7.875%
7.20% Senior notes due 2027
Guarantor Obligations [Line Items]
Senior Note Maturity Year	2027
Debt instrument interest rate stated percentage	7.20%
Notes Issued	$ 112,100,000

Guarantee Of Registered Secur_4

Guarantee Of Registered Securities (Condensed Consolidating Statements Of Income) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Guarantor Obligations [Line Items]
Revenues	$ 512.1	$ 551.3	$ 583.9	$ 405.9	$ 399	$ 430.9	$ 458.5	$ 417	$ 2,053.2	$ 1,705.4	$ 1,843
Contract drilling (exclusive of depreciation)	476.6	496.5	500.3	332.6	322.8	327.1	344.3	325.2	1,806	1,319.4	1,189.5
Loss on impairment	13.3	88.2	2.5	0	40.3	0	0	0	104	40.3	182.9
Depreciation expense	163.8	163	157.9	125	122.4	120.6	120.7	115.2	609.7	478.9	444.8
General and administrative	42	36.1	81.2	29.6	23.6	25.1	26.1	27.9	188.9	102.7	157.8
Costs and Expenses									2,708.6	1,941.3	1,975
EQUITY IN EARNINGS OF ARO	(9.5)	(3.7)	0.6	0					(12.6)	0	0
OPERATING LOSS	(193.1)	(236.2)	(157.4)	(81.3)	(110.1)	(41.9)	(32.6)	(51.3)	(668)	(235.9)	(132)
Other income (expense), net	41.9	40.2	597.3	(75.2)	(69.8)	(77.7)	(84.8)	(70.7)	604.2	(303)	(64)
LOSS FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	(151.2)	(196)	439.9	(156.5)	(179.9)	(119.6)	(117.4)	(122)	(63.8)	(538.9)	(196)
Total provision for income taxes	62.8	1.5	32.6	31.5	23.2	23.3	24.7	18.4	128.4	89.6	109.2
INCOME (LOSS) FROM DISCONTINUED OPERATIONS, NET					0	0	(8)	(0.1)	0	(8.1)	1
Equity in Earnings of Subsidiaries Net of Tax									0	0	0
NET LOSS	(214)	(197.5)	407.3	(188)	(203.1)	(142.9)	(150.1)	(140.5)	(192.2)	(636.6)	(304.2)
NET (INCOME) LOSS ATTRIBUTABLE TO NONCONTROLLING INTERESTS	(2)	0.4	(1.8)	(2.4)	(0.5)	(2.1)	(0.9)	0.4	(5.8)	(3.1)	0.5
NET LOSS ATTRIBUTABLE TO VALARIS	$ (216)	$ (197.1)	$ 405.5	$ (190.4)	$ (203.6)	$ (145)	$ (151)	$ (140.1)	(198)	(639.7)	(303.7)
Ensco Plc [Member]
Guarantor Obligations [Line Items]
Revenues									56.7	49.5	52.9
Contract drilling (exclusive of depreciation)									82.6	51	50
Loss on impairment									0	0	0
Depreciation expense									0.1	0	0
General and administrative									85.5	46.3	45.4
Costs and Expenses									168.2
OPERATING LOSS									(111.5)	(47.8)	(42.5)
Other income (expense), net									723.9	2.7	(6.8)
LOSS FROM CONTINUING OPERATIONS BEFORE INCOME TAXES									612.4	(45.1)	(49.3)
Total provision for income taxes									0	0	0
INCOME (LOSS) FROM DISCONTINUED OPERATIONS, NET										0	0
Equity in Earnings of Subsidiaries Net of Tax									(810.4)	(594.6)	(254.4)
NET LOSS									(198)	(639.7)	(303.7)
NET (INCOME) LOSS ATTRIBUTABLE TO NONCONTROLLING INTERESTS									0	0	0
NET LOSS ATTRIBUTABLE TO VALARIS									(198)	(639.7)	(303.7)
ENSCO International Inc. [Member]
Guarantor Obligations [Line Items]
Revenues									165.5	155.2	163.3
Contract drilling (exclusive of depreciation)									147.1	139.5	149.9
Loss on impairment									0	0	0
Depreciation expense									17.3	14.2	15.9
General and administrative									0.4	0.4	50.8
Costs and Expenses									164.8
OPERATING LOSS									0.7	1.1	(53.3)
Other income (expense), net									(35.7)	(135.2)	(110.5)
LOSS FROM CONTINUING OPERATIONS BEFORE INCOME TAXES									(35)	(134.1)	(163.8)
Total provision for income taxes									39.8	43.3	45
INCOME (LOSS) FROM DISCONTINUED OPERATIONS, NET										0	0
Equity in Earnings of Subsidiaries Net of Tax									47.8	121.8	129.6
NET LOSS									(27)	(55.6)	(79.2)
NET (INCOME) LOSS ATTRIBUTABLE TO NONCONTROLLING INTERESTS									0	0	0
NET LOSS ATTRIBUTABLE TO VALARIS									(27)	(55.6)	(79.2)
Pride International Inc. [Member]
Guarantor Obligations [Line Items]
Revenues									0	0	0
Contract drilling (exclusive of depreciation)									0	0	0
Loss on impairment									0	0	0
Depreciation expense									0	0	0
General and administrative									0	0	0
Costs and Expenses									0
OPERATING LOSS									0	0	0
Other income (expense), net									(80.8)	(89)	(71.7)
LOSS FROM CONTINUING OPERATIONS BEFORE INCOME TAXES									(80.8)	(89)	(71.7)
Total provision for income taxes									0	0	0
INCOME (LOSS) FROM DISCONTINUED OPERATIONS, NET										0	0
Equity in Earnings of Subsidiaries Net of Tax									25	93.3	84.2
NET LOSS									(55.8)	4.3	12.5
NET (INCOME) LOSS ATTRIBUTABLE TO NONCONTROLLING INTERESTS									0	0	0
NET LOSS ATTRIBUTABLE TO VALARIS									(55.8)	4.3	12.5
Other Non-Guarantor Subsidiaries Of Ensco [Member]
Guarantor Obligations [Line Items]
Revenues									2,168.9	1,802.8	1,941.2
Contract drilling (exclusive of depreciation)									1,914.2	1,431	1,304
Loss on impairment									104	40.3	182.9
Depreciation expense									592.3	464.7	428.9
General and administrative									103	56	61.6
Costs and Expenses									2,713.5
EQUITY IN EARNINGS OF ARO									(12.6)
OPERATING LOSS									(557.2)	(189.2)	(36.2)
Other income (expense), net									(20.2)	(109)	110.5
LOSS FROM CONTINUING OPERATIONS BEFORE INCOME TAXES									(577.4)	(298.2)	74.3
Total provision for income taxes									88.6	46.3	64.2
INCOME (LOSS) FROM DISCONTINUED OPERATIONS, NET										(8.1)	1
Equity in Earnings of Subsidiaries Net of Tax									0	0	0
NET LOSS									(666)	(352.6)	11.1
NET (INCOME) LOSS ATTRIBUTABLE TO NONCONTROLLING INTERESTS									(5.8)	(3.1)	0.5
NET LOSS ATTRIBUTABLE TO VALARIS									(671.8)	(355.7)	11.6
Consolidating Adjustments [Member]
Guarantor Obligations [Line Items]
Revenues									(337.9)	(302.1)	(314.4)
Contract drilling (exclusive of depreciation)									(337.9)	(302.1)	(314.4)
Loss on impairment									0	0	0
Depreciation expense									0	0	0
General and administrative									0	0	0
Costs and Expenses									(337.9)
OPERATING LOSS									0	0	0
Other income (expense), net									17	27.5	14.5
LOSS FROM CONTINUING OPERATIONS BEFORE INCOME TAXES									17	27.5	14.5
Total provision for income taxes									0	0	0
INCOME (LOSS) FROM DISCONTINUED OPERATIONS, NET										0	0
Equity in Earnings of Subsidiaries Net of Tax									737.6	379.5	40.6
NET LOSS									754.6	407	55.1
NET (INCOME) LOSS ATTRIBUTABLE TO NONCONTROLLING INTERESTS									0	0	0
NET LOSS ATTRIBUTABLE TO VALARIS									$ 754.6	$ 407	$ 55.1

Guarantee Of Registered Secur_5

Guarantee Of Registered Securities (Condensed Consolidating Statements Of Comprehensive Income) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Guarantor Obligations [Line Items]
NET LOSS	$ (214)	$ (197.5)	$ 407.3	$ (188)	$ (203.1)	$ (142.9)	$ (150.1)	$ (140.5)	$ (192.2)	$ (636.6)	$ (304.2)
OTHER COMPREHENSIVE INCOME (LOSS), NET
Increase (Decrease) in Obligation, Pension and Other Postretirement Benefits									(21.7)	0	0
Net change in fair value of derivatives									1.6	(9.7)	8.5
Reclassification of net (gains) losses on derivative instruments from other comprehensive income (loss) into net loss									8.3	(1)	0.4
Other									(0.2)	(0.5)	0.7
NET OTHER COMPREHENSIVE INCOME (LOSS)									(12)	(11.2)	9.6
COMPREHENSIVE LOSS									(204.2)	(647.8)	(294.6)
COMPREHENSIVE INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS									(5.8)	(3.1)	0.5
COMPREHENSIVE LOSS ATTRIBUTABLE TO VALARIS									(210)	(650.9)	(294.1)
Ensco Plc [Member]
Guarantor Obligations [Line Items]
NET LOSS									(198)	(639.7)	(303.7)
OTHER COMPREHENSIVE INCOME (LOSS), NET
Increase (Decrease) in Obligation, Pension and Other Postretirement Benefits									0
Net change in fair value of derivatives									0	0	0
Reclassification of net (gains) losses on derivative instruments from other comprehensive income (loss) into net loss									0	0	0
Other									0	0	0
NET OTHER COMPREHENSIVE INCOME (LOSS)									0	0	0
COMPREHENSIVE LOSS									(198)	(639.7)	(303.7)
COMPREHENSIVE INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS									0	0	0
COMPREHENSIVE LOSS ATTRIBUTABLE TO VALARIS									(198)	(639.7)	(303.7)
ENSCO International Inc. [Member]
Guarantor Obligations [Line Items]
NET LOSS									(27)	(55.6)	(79.2)
OTHER COMPREHENSIVE INCOME (LOSS), NET
Increase (Decrease) in Obligation, Pension and Other Postretirement Benefits									0
Net change in fair value of derivatives									1.6	(9.7)	8.5
Reclassification of net (gains) losses on derivative instruments from other comprehensive income (loss) into net loss									8.3	(1)	0.4
Other									0	0	0
NET OTHER COMPREHENSIVE INCOME (LOSS)									9.9	(10.7)	8.9
COMPREHENSIVE LOSS									(17.1)	(66.3)	(70.3)
COMPREHENSIVE INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS									0	0	0
COMPREHENSIVE LOSS ATTRIBUTABLE TO VALARIS									(17.1)	(66.3)	(70.3)
Pride International Inc. [Member]
Guarantor Obligations [Line Items]
NET LOSS									(55.8)	4.3	12.5
OTHER COMPREHENSIVE INCOME (LOSS), NET
Increase (Decrease) in Obligation, Pension and Other Postretirement Benefits									0
Net change in fair value of derivatives									0	0	0
Reclassification of net (gains) losses on derivative instruments from other comprehensive income (loss) into net loss									0	0	0
Other									0	0	0
NET OTHER COMPREHENSIVE INCOME (LOSS)									0	0	0
COMPREHENSIVE LOSS									(55.8)	4.3	12.5
COMPREHENSIVE INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS									0	0	0
COMPREHENSIVE LOSS ATTRIBUTABLE TO VALARIS									(55.8)	4.3	12.5
Other Non-Guarantor Subsidiaries Of Ensco [Member]
Guarantor Obligations [Line Items]
NET LOSS									(666)	(352.6)	11.1
OTHER COMPREHENSIVE INCOME (LOSS), NET
Increase (Decrease) in Obligation, Pension and Other Postretirement Benefits									(21.7)
Net change in fair value of derivatives									0	0	0
Reclassification of net (gains) losses on derivative instruments from other comprehensive income (loss) into net loss									0	0	0
Other									(0.2)	(0.5)	0.7
NET OTHER COMPREHENSIVE INCOME (LOSS)									(21.9)	(0.5)	0.7
COMPREHENSIVE LOSS									(687.9)	(353.1)	11.8
COMPREHENSIVE INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS									(5.8)	(3.1)	0.5
COMPREHENSIVE LOSS ATTRIBUTABLE TO VALARIS									(693.7)	(356.2)	12.3
Consolidating Adjustments [Member]
Guarantor Obligations [Line Items]
NET LOSS									754.6	407	55.1
OTHER COMPREHENSIVE INCOME (LOSS), NET
Increase (Decrease) in Obligation, Pension and Other Postretirement Benefits									0
Net change in fair value of derivatives									0	0	0
Reclassification of net (gains) losses on derivative instruments from other comprehensive income (loss) into net loss									0	0	0
Other									0	0	0
NET OTHER COMPREHENSIVE INCOME (LOSS)									0	0	0
COMPREHENSIVE LOSS									754.6	407	55.1
COMPREHENSIVE INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS									0	0	0
COMPREHENSIVE LOSS ATTRIBUTABLE TO VALARIS									$ 754.6	$ 407	$ 55.1

Guarantee Of Registered Secur_6

Guarantee Of Registered Securities (Condensed Consolidating Balance Sheets) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Guarantor Obligations [Line Items]
Cash and cash equivalents	$ 97.2	$ 275.1	$ 445.4	$ 1,159.7
Short-term Investments	0	329
Accounts receivable	520.7	344.7
Accounts receivable from affiliates	0	0
Other	446.5	360.9
Total current assets	1,064.4	1,309.7
PROPERTY AND EQUIPMENT, AT COST	18,393.8	15,517
Less accumulated depreciation	3,296.9	2,900.8
Property and equipment, net	15,096.9	12,616.2	12,873.7
Due from Joint Ventures, Noncurrent	452.9	0
INVESTMENT IN ARO	128.7	0
DUE FROM AFFILIATES	0	0
Investment in Affiliates	0	0
OTHER ASSETS	188.3	97.8
TOTAL ASSETS	16,931.2	14,023.7
Accounts payable and accrued liabilities	705.9	528.5
Accounts payable to affiliates	0	0
Current maturities of long-term debt	124.8	0
Total current liabilities	830.7	528.5
DUE TO AFFILIATES	0	0
LONG-TERM DEBT	5,923.5	5,010.4
OTHER LIABILITIES	867.4	396
ENSCO SHAREHOLDERS' EQUITY	9,310.9	8,091.4
NONCONTROLLING INTERESTS	(1.3)	(2.6)
Total equity	9,309.6	8,088.8
Total liabilities and shareholders' equity	16,931.2	14,023.7
Ensco Plc [Member]
Guarantor Obligations [Line Items]
Cash and cash equivalents	21.5	199.8	185.2	892.6
Short-term Investments	0	329
Accounts receivable	0.2	7.3
Accounts receivable from affiliates	4,031.4	1,861.2
Other	0.6	0.6
Total current assets	4,053.7	2,397.9
PROPERTY AND EQUIPMENT, AT COST	1.9	1.8
Less accumulated depreciation	1.9	1.8
Property and equipment, net	0	0
Due from Joint Ventures, Noncurrent	0
INVESTMENT IN ARO	0
DUE FROM AFFILIATES	73.8	2,413.8
Investment in Affiliates	9,778.5	8,522.6
OTHER ASSETS	7.9	8.1
TOTAL ASSETS	13,913.9	13,342.4
Accounts payable and accrued liabilities	99.2	85.3
Accounts payable to affiliates	818.8	59.7
Current maturities of long-term debt	0
Total current liabilities	918	145
DUE TO AFFILIATES	710.3	1,432
LONG-TERM DEBT	2,990.6	3,676.5
OTHER LIABILITIES	(14.6)	0.1
ENSCO SHAREHOLDERS' EQUITY	9,309.6	8,088.8
NONCONTROLLING INTERESTS	0	0
Total equity	9,309.6	8,088.8
Total liabilities and shareholders' equity	13,913.9	13,342.4
ENSCO International Inc. [Member]
Guarantor Obligations [Line Items]
Cash and cash equivalents	0	0	0	0
Short-term Investments		0
Accounts receivable	19.7	25.4
Accounts receivable from affiliates	386	171.4
Other	11.6	6
Total current assets	417.3	202.8
PROPERTY AND EQUIPMENT, AT COST	108.8	125.2
Less accumulated depreciation	84.7	91.3
Property and equipment, net	24.1	33.9
Due from Joint Ventures, Noncurrent	0
INVESTMENT IN ARO	0
DUE FROM AFFILIATES	0	234.5
Investment in Affiliates	788.8	3,713.7
OTHER ASSETS	3.8	0
TOTAL ASSETS	1,234	4,184.9
Accounts payable and accrued liabilities	29.3	32
Accounts payable to affiliates	147.8	139.5
Current maturities of long-term debt	0
Total current liabilities	177.1	171.5
DUE TO AFFILIATES	478.8	1,226.9
LONG-TERM DEBT	111.7	149.3
OTHER LIABILITIES	90.6	64.3
ENSCO SHAREHOLDERS' EQUITY	375.8	2,572.9
NONCONTROLLING INTERESTS	0	0
Total equity	375.8	2,572.9
Total liabilities and shareholders' equity	1,234	4,184.9
Pride International Inc. [Member]
Guarantor Obligations [Line Items]
Cash and cash equivalents	0	2.7	25.6	19.8
Short-term Investments		0
Accounts receivable		0
Accounts receivable from affiliates		0
Other		0
Total current assets	0	2.7
PROPERTY AND EQUIPMENT, AT COST		0
Less accumulated depreciation		0
Property and equipment, net	0	0
Due from Joint Ventures, Noncurrent	0
INVESTMENT IN ARO	0
DUE FROM AFFILIATES	38.9	125
Investment in Affiliates	1,224.9	1,199.9
OTHER ASSETS	0	0
TOTAL ASSETS	1,263.8	1,327.6
Accounts payable and accrued liabilities	12.2	12.7
Accounts payable to affiliates	815.1	38.2
Current maturities of long-term debt	124.8
Total current liabilities	952.1	50.9
DUE TO AFFILIATES	586.6	1,366.5
LONG-TERM DEBT	373.3	502.6
OTHER LIABILITIES	0	0
ENSCO SHAREHOLDERS' EQUITY	(648.2)	(592.4)
NONCONTROLLING INTERESTS	0	0
Total equity	(648.2)	(592.4)
Total liabilities and shareholders' equity	1,263.8	1,327.6
Other Non-Guarantor Subsidiaries Of Ensco [Member]
Guarantor Obligations [Line Items]
Cash and cash equivalents	75.7	72.6	234.6	247.3
Short-term Investments	0	0
Accounts receivable	500.8	312
Accounts receivable from affiliates	897.2	131.7
Other	434.3	354.3
Total current assets	1,908	870.6
PROPERTY AND EQUIPMENT, AT COST	18,283.1	15,390
Less accumulated depreciation	3,210.3	2,807.7
Property and equipment, net	15,072.8	12,582.3
Due from Joint Ventures, Noncurrent	452.9
INVESTMENT IN ARO	128.7
DUE FROM AFFILIATES	1,775.7	2,715.1
Investment in Affiliates	0	0
OTHER ASSETS	182.6	89.7
TOTAL ASSETS	19,520.7	16,257.7
Accounts payable and accrued liabilities	565.2	398.5
Accounts payable to affiliates	3,532.9	1,926.9
Current maturities of long-term debt	0
Total current liabilities	4,098.1	2,325.4
DUE TO AFFILIATES	112.7	1,463
LONG-TERM DEBT	2,447.9	682
OTHER LIABILITIES	797.4	331.6
ENSCO SHAREHOLDERS' EQUITY	12,065.9	11,458.3
NONCONTROLLING INTERESTS	(1.3)	(2.6)
Total equity	12,064.6	11,455.7
Total liabilities and shareholders' equity	19,520.7	16,257.7
Consolidating Adjustments [Member]
Guarantor Obligations [Line Items]
Cash and cash equivalents	0	0	$ 0	$ 0
Short-term Investments		0
Accounts receivable	0	0
Accounts receivable from affiliates	(5,314.6)	(2,164.3)
Other		0
Total current assets	(5,314.6)	(2,164.3)
PROPERTY AND EQUIPMENT, AT COST		0
Less accumulated depreciation		0
Property and equipment, net	0	0
Due from Joint Ventures, Noncurrent	0
INVESTMENT IN ARO	0
DUE FROM AFFILIATES	(1,888.4)	(5,488.4)
Investment in Affiliates	(11,792.2)	(13,436.2)
OTHER ASSETS	(6)	0
TOTAL ASSETS	(19,001.2)	(21,088.9)
Accounts payable and accrued liabilities	0	0
Accounts payable to affiliates	(5,314.6)	(2,164.3)
Current maturities of long-term debt	0
Total current liabilities	(5,314.6)	(2,164.3)
DUE TO AFFILIATES	(1,888.4)	(5,488.4)
LONG-TERM DEBT	0	0
OTHER LIABILITIES	(6)	0
ENSCO SHAREHOLDERS' EQUITY	(11,792.2)	(13,436.2)
NONCONTROLLING INTERESTS	0	0
Total equity	(11,792.2)	(13,436.2)
Total liabilities and shareholders' equity	$ (19,001.2)	$ (21,088.9)

Guarantee Of Registered Secur_7

Guarantee Of Registered Securities (Condensed Consolidating Statements Of Cash Flows) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Guarantor Obligations [Line Items]
NET LOSS	$ (214)	$ (197.5)	$ 407.3	$ (188)	$ (203.1)	$ (142.9)	$ (150.1)	$ (140.5)	$ (192.2)	$ (636.6)	$ (304.2)
OPERATING ACTIVITIES
Net cash provided by operating activities of continuing operations									(276.9)	(55.7)	259.4
INVESTING ACTIVITIES
Acquisition of Rowan, net of cash acquired									931.9	0	0
Maturities of short-term investments									474	1,030	2,042.5
Purchases of short-term investments									(145)	(919)	(1,040)
Purchase of Affiliate Debt										0	0
Payments to Acquire Businesses, Net of Cash Acquired									0	0	871.6
Sale of affiliate debt										0
Additions to property and equipment									(227)	(426.7)	(536.7)
Net proceeds from disposition of assets									17.7	11	2.8
Other									0
Net cash used in investing activities of continuing operations									1,051.6	(304.7)	(403)
FINANCING ACTIVITIES
Reduction of long-term borrowings									(928.1)	(771.2)	(537)
Borrowings on credit facility									215	0	0
Repayments of credit facility borrowings									(215)	0	0
Proceeds from issuance of senior notes									0	1,000	0
Debt solicitation fees									(9.5)	0	0
Cash dividends paid									(4.5)	(17.9)	(13.8)
Debt issuance costs									0	(17)	(12)
Payments for (Proceeds from) Businesses and Interest in Affiliates									0	0	0
Other									(10.2)	(5.7)	(7.7)
Net cash provided by (used in) financing activities									(952.3)	188.2	(570.5)
Net cash provided by (used in) discontinued operations									0	2.5	(0.8)
Effect of exchange rate changes on cash and cash equivalents									(0.3)	(0.6)	0.6
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS									(177.9)	(170.3)	(714.3)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR				275.1				445.4	275.1	445.4	1,159.7
CASH AND CASH EQUIVALENTS, END OF YEAR	97.2				275.1				97.2	275.1	445.4
Ensco Plc [Member]
Guarantor Obligations [Line Items]
NET LOSS									(198)	(639.7)	(303.7)
OPERATING ACTIVITIES
Net cash provided by operating activities of continuing operations									(181.2)	18.1	(18.2)
INVESTING ACTIVITIES
Acquisition of Rowan, net of cash acquired									0
Maturities of short-term investments									474	1,030	1,748
Purchases of short-term investments									(145)	(919)	(1,022.9)
Purchase of Affiliate Debt										(551.7)	(316.3)
Payments to Acquire Businesses, Net of Cash Acquired											0
Sale of affiliate debt										479
Additions to property and equipment									0	0	0
Net proceeds from disposition of assets										0	0
Other									(0.1)
Net cash used in investing activities of continuing operations									328.9	38.3	408.8
FINANCING ACTIVITIES
Reduction of long-term borrowings									(536.6)	(159.9)	(220.7)
Borrowings on credit facility									215
Repayments of credit facility borrowings									(215)
Proceeds from issuance of senior notes										1,000
Debt solicitation fees									0
Cash dividends paid									(4.5)	(17.9)	(13.8)
Debt issuance costs										(17)	(12)
Payments for (Proceeds from) Businesses and Interest in Affiliates									220.6	(845)	(848.9)
Other									(5.5)	(2)	(2.6)
Net cash provided by (used in) financing activities									(326)	(41.8)	(1,098)
Net cash provided by (used in) discontinued operations										0	0
Effect of exchange rate changes on cash and cash equivalents									0	0	0
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS									(178.3)	14.6	(707.4)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR				199.8				185.2	199.8	185.2	892.6
CASH AND CASH EQUIVALENTS, END OF YEAR	21.5				199.8				21.5	199.8	185.2
ENSCO International Inc. [Member]
Guarantor Obligations [Line Items]
NET LOSS									(27)	(55.6)	(79.2)
OPERATING ACTIVITIES
Net cash provided by operating activities of continuing operations									(57.9)	(135.1)	(117.6)
INVESTING ACTIVITIES
Acquisition of Rowan, net of cash acquired									0
Maturities of short-term investments									0	0	5.5
Purchases of short-term investments									0	0	0
Purchase of Affiliate Debt										0	0
Payments to Acquire Businesses, Net of Cash Acquired											0
Sale of affiliate debt										0
Additions to property and equipment									0	0	0
Net proceeds from disposition of assets									0		0
Other									0
Net cash used in investing activities of continuing operations									0	0	5.5
FINANCING ACTIVITIES
Reduction of long-term borrowings									(30.4)	0	0
Borrowings on credit facility									0
Repayments of credit facility borrowings									0
Proceeds from issuance of senior notes										0
Debt solicitation fees									0
Cash dividends paid									0	0	0
Debt issuance costs										0	0
Payments for (Proceeds from) Businesses and Interest in Affiliates									88.3	135.1	112.1
Other									0	0	0
Net cash provided by (used in) financing activities									57.9	135.1	112.1
Net cash provided by (used in) discontinued operations										0	0
Effect of exchange rate changes on cash and cash equivalents									0	0	0
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS									0	0	0
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR				0				0	0	0	0
CASH AND CASH EQUIVALENTS, END OF YEAR	0				0				0	0	0
Pride International Inc. [Member]
Guarantor Obligations [Line Items]
NET LOSS									(55.8)	4.3	12.5
OPERATING ACTIVITIES
Net cash provided by operating activities of continuing operations									(111.3)	(97.6)	(100.1)
INVESTING ACTIVITIES
Acquisition of Rowan, net of cash acquired									0
Maturities of short-term investments									0	0	0
Purchases of short-term investments									0	0	0
Purchase of Affiliate Debt										0	0
Payments to Acquire Businesses, Net of Cash Acquired											0
Sale of affiliate debt										0
Additions to property and equipment									0	0	0
Net proceeds from disposition of assets									0		0
Other									0
Net cash used in investing activities of continuing operations									0	0	0
FINANCING ACTIVITIES
Reduction of long-term borrowings									0	(537.8)	0
Borrowings on credit facility									0
Repayments of credit facility borrowings									0
Proceeds from issuance of senior notes										0
Debt solicitation fees									0
Cash dividends paid									0	0	0
Debt issuance costs										0	0
Payments for (Proceeds from) Businesses and Interest in Affiliates									108.6	612.5	105.9
Other									0	0	0
Net cash provided by (used in) financing activities									108.6	74.7	105.9
Net cash provided by (used in) discontinued operations										0	0
Effect of exchange rate changes on cash and cash equivalents									0	0	0
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS									(2.7)	(22.9)	5.8
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR				2.7				25.6	2.7	25.6	19.8
CASH AND CASH EQUIVALENTS, END OF YEAR	0				2.7				0	2.7	25.6
Other Non-Guarantor Subsidiaries Of Ensco [Member]
Guarantor Obligations [Line Items]
NET LOSS									(666)	(352.6)	11.1
OPERATING ACTIVITIES
Net cash provided by operating activities of continuing operations									73.5	158.9	495.3
INVESTING ACTIVITIES
Acquisition of Rowan, net of cash acquired									931.9
Maturities of short-term investments									0	0	289
Purchases of short-term investments									0	0	(17.1)
Purchase of Affiliate Debt										0	0
Payments to Acquire Businesses, Net of Cash Acquired											871.6
Sale of affiliate debt										0
Additions to property and equipment									(227)	(426.7)	(536.7)
Net proceeds from disposition of assets									17.7	11	2.8
Other									0.1
Net cash used in investing activities of continuing operations									722.7	(415.7)	(1,133.6)
FINANCING ACTIVITIES
Reduction of long-term borrowings									(361.1)	(0.8)	0
Borrowings on credit facility									0
Repayments of credit facility borrowings									0
Proceeds from issuance of senior notes										0
Debt solicitation fees									(9.5)
Cash dividends paid									0	0	0
Debt issuance costs										0	0
Payments for (Proceeds from) Businesses and Interest in Affiliates									(417.5)	97.4	630.9
Other									(4.7)	(3.7)	(5.1)
Net cash provided by (used in) financing activities									(792.8)	92.9	625.8
Net cash provided by (used in) discontinued operations										2.5	(0.8)
Effect of exchange rate changes on cash and cash equivalents									(0.3)	(0.6)	0.6
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS									3.1	(162)	(12.7)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR				72.6				234.6	72.6	234.6	247.3
CASH AND CASH EQUIVALENTS, END OF YEAR	75.7				72.6				75.7	72.6	234.6
Consolidating Adjustments [Member]
Guarantor Obligations [Line Items]
NET LOSS									754.6	407	55.1
OPERATING ACTIVITIES
Net cash provided by operating activities of continuing operations									0	0	0
INVESTING ACTIVITIES
Acquisition of Rowan, net of cash acquired									0
Maturities of short-term investments									0	0	0
Purchases of short-term investments									0	0	0
Purchase of Affiliate Debt										551.7	316.3
Payments to Acquire Businesses, Net of Cash Acquired											0
Sale of affiliate debt										(479)
Additions to property and equipment									0	0	0
Net proceeds from disposition of assets									0	0	0
Other									0
Net cash used in investing activities of continuing operations									0	72.7	316.3
FINANCING ACTIVITIES
Reduction of long-term borrowings									0	(72.7)	(316.3)
Borrowings on credit facility									0
Repayments of credit facility borrowings									0
Proceeds from issuance of senior notes										0
Debt solicitation fees									0
Cash dividends paid									0	0	0
Debt issuance costs										0	0
Payments for (Proceeds from) Businesses and Interest in Affiliates									0	0	0
Other									0	0	0
Net cash provided by (used in) financing activities									0	(72.7)	(316.3)
Net cash provided by (used in) discontinued operations										0	0
Effect of exchange rate changes on cash and cash equivalents									0	0	0
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS									0	0	0
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR				$ 0				$ 0	0	0	0
CASH AND CASH EQUIVALENTS, END OF YEAR	$ 0				$ 0				$ 0	$ 0	$ 0

Unaudited Quarterly Financial_3

Unaudited Quarterly Financial Data (Summary Of Unaudited Quarterly Consolidated Income Statement) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Quarterly Financial Data [Abstract]
Revenues	$ 512.1	$ 551.3	$ 583.9	$ 405.9	$ 399	$ 430.9	$ 458.5	$ 417	$ 2,053.2	$ 1,705.4	$ 1,843
Cost of Goods and Services Sold	476.6	496.5	500.3	332.6	322.8	327.1	344.3	325.2	1,806	1,319.4	1,189.5
Loss on impairment	13.3	88.2	2.5	0	40.3	0	0	0	104	40.3	182.9
Depreciation expense	163.8	163	157.9	125	122.4	120.6	120.7	115.2	609.7	478.9	444.8
General and administrative	42	36.1	81.2	29.6	23.6	25.1	26.1	27.9	188.9	102.7	157.8
EQUITY IN EARNINGS OF ARO	(9.5)	(3.7)	0.6	0					(12.6)	0	0
OPERATING LOSS	(193.1)	(236.2)	(157.4)	(81.3)	(110.1)	(41.9)	(32.6)	(51.3)	(668)	(235.9)	(132)
Other income (expense), net	41.9	40.2	597.3	(75.2)	(69.8)	(77.7)	(84.8)	(70.7)	604.2	(303)	(64)
LOSS FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	(151.2)	(196)	439.9	(156.5)	(179.9)	(119.6)	(117.4)	(122)	(63.8)	(538.9)	(196)
Provision for income taxes	62.8	1.5	32.6	31.5	23.2	23.3	24.7	18.4	128.4	89.6	109.2
LOSS FROM CONTINUING OPERATIONS					(203.1)	(142.9)	(142.1)	(140.4)	(192.2)	(628.5)	(305.2)
INCOME (LOSS) FROM DISCONTINUED OPERATIONS, NET					0	0	(8)	(0.1)	0	(8.1)	1
NET LOSS	(214)	(197.5)	407.3	(188)	(203.1)	(142.9)	(150.1)	(140.5)	(192.2)	(636.6)	(304.2)
NET (INCOME) LOSS ATTRIBUTABLE TO NONCONTROLLING INTERESTS	(2)	0.4	(1.8)	(2.4)	(0.5)	(2.1)	(0.9)	0.4	(5.8)	(3.1)	0.5
NET LOSS ATTRIBUTABLE TO VALARIS	$ (216)	$ (197.1)	$ 405.5	$ (190.4)	$ (203.6)	$ (145)	$ (151)	$ (140.1)	$ (198)	$ (639.7)	$ (303.7)
Income (loss) per share – basic and diluted
Continuing operations	$ (1.09)	$ (1)	$ 2.09	$ (1.75)	$ (1.88)	$ (1.34)	$ (1.31)	$ (1.29)	$ (1.14)	$ (5.82)	$ (3.66)
Discontinued operations	0	0	0	0	0	0	(0.08)	0	0	(0.08)	0
Total earnings per share - basic	$ (1.09)	$ (1)	$ 2.09	$ (1.75)	$ (1.88)	$ (1.34)	$ (1.39)	$ (1.29)	$ (1.14)	$ (5.90)	$ (3.66)