Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
CURRENT ASSETS
Cash and cash equivalents	$ 445.4	$ 1,159.7
Short-term Investments	440.0	1,442.6
Accounts receivable, net	345.4	361.0
Other	381.2	316.0
Total current assets	1,612.0	3,279.3
PROPERTY AND EQUIPMENT, AT COST	15,332.1	12,992.5
Less accumulated depreciation	2,458.4	2,073.2
Property and equipment, net	12,873.7	10,919.3
OTHER ASSETS, NET	140.2	175.9
TOTAL ASSETS	14,625.9	14,374.5
CURRENT LIABILITIES
Accounts payable - trade	432.6	145.9
Accrued liabilities and other	325.9	376.6
Current maturities of long-term debt	0.0	331.9
Total current liabilities	758.5	854.4
LONG-TERM DEBT	4,750.7	4,942.6
OTHER LIABILITIES	386.7	322.5
COMMITMENTS AND CONTINGENCIES
ENSCO SHAREHOLDERS' EQUITY
Additional paid-in capital	7,195.0	6,402.2
Retained earnings	1,532.7	1,864.1
Accumulated other comprehensive income	28.6	19.0
Treasury shares, at cost, 11.1 million and 7.3 million shares as of December 31, 2017 and 2016	(69.0)	(65.8)
Total Ensco shareholders' equity	8,732.1	8,250.6
NONCONTROLLING INTERESTS	(2.1)	4.4
Total equity	8,730.0	8,255.0
Total liabilities and shareholders' equity	14,625.9	14,374.5
Class A Ordinary Shares, U.S. [Member]
ENSCO SHAREHOLDERS' EQUITY
Common shares, value	44.7	31.0
Common Class B, Par Value In GBP [Member]
ENSCO SHAREHOLDERS' EQUITY
Common shares, value	$ 0.1	$ 0.1

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Name:	us-gaap_AccountsPayableCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.14)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682