Guarantees of Registered Securities (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
CURRENT ASSETS:
Cash and cash equivalents	$ 1,005,898	$ 665,637	$ 1,005,898	$ 665,637
Receivables - trade and other	470,299		470,299		423,839
Other current assets	87,176		87,176		81,749
Assets of discontinued operations	23,559		23,559		22,954
Total current assets	1,586,932		1,586,932		1,552,550
Property, plant and equipment - gross	7,887,865		7,887,865		7,661,093
Less accumulated depreciation and amortization	1,677,712		1,677,712		1,589,364
Property, plant and equipment - net	6,210,153		6,210,153		6,071,729
Investments in subsidiaries	0		0		0
Due from affiliates	0		0		0
Other assets	67,708		67,708		75,208
TOTAL ASSETS	7,864,793		7,864,793		7,699,487
CURRENT LIABILITIES:
Accounts payable - trade	77,627		77,627		83,004
Deferred revenues	55,084		55,084		52,340
Accrued liabilities	100,822		100,822		137,495
Liabilities of discontinued operations	21,255		21,255		21,255
Total current liabilities	254,788		254,788		294,094
Long-term debt	2,009,152		2,009,152		2,009,598
Due to affiliates	0		0		0
Other liabilities	401,945		401,945		390,199
Deferred income taxes - net	495,401		495,401		473,872
Shareholders' equity	4,703,507		4,703,507		4,531,724
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	7,864,793		7,864,793		7,699,487
Condensed Consolidating Income Statements [Abstract]
REVENUES	408,883	351,018	803,121	684,495
COSTS AND EXPENSES:
Direct operating costs (excluding items below)	216,044	188,114	425,513	370,253
Depreciation and amortization	66,531	61,330	131,147	120,296
Selling, general and administrative	33,263	25,098	62,694	48,154
Loss (gain) on disposals of property and equipment	(19,222)	(2,063)	(18,914)	(2,119)
Material charges and other operating expenses		8,126		12,697
Total costs and expenses	296,616	280,605	600,440	549,281
INCOME (LOSS) FROM OPERATIONS	112,267	70,413	202,681	135,214
OTHER INCOME (EXPENSE):
Interest expense, net of interest capitalized	(17,685)	(12,993)	(36,266)	(24,250)
Interest income	368	146	727	260
Loss on extinguishment of debt	0	(11,767)	0	(11,767)
Other - net	(443)	(122)	(1,237)	1,215
Total other income (expense) - net	(17,760)	(24,736)	(36,776)	(34,542)
INCOME (LOSS) FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	94,507	45,677	165,905	100,672
(Benefit) provision for income taxes	11,663	(5,171)	14,927	(5,675)
NET INCOME FROM CONTINUING OPERATIONS	82,844	50,848	150,978	106,347
DISCONTINUED OPERATIONS, NET OF TAX		(1,413)		(7,395)
EQUITY IN EARNINGS OF SUBSIDIARIES, NET OF TAX	0	0	0	0
NET INCOME	82,844	49,435	150,978	98,952
Statement of Comprehensive Income [Abstract]
Net income	82,844	49,435	150,978	98,952
Pension and other postretirement benefit adjustments, net of income taxes
Amortization of net loss	4,447	4,087	8,859	8,174
Amortization of transition obligation	0	77	0	154
Amortization of prior service credit	(790)	(776)	(1,574)	(1,551)
OTHER COMPREHENSIVE INCOME	3,657	3,388	7,285	6,777
COMPREHENSIVE INCOME	86,501	52,823	158,263	105,729
Consolidated Statement of Cash Flows [Abstract]
NET CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES			234,332	162,811
INVESTING ACTIVITIES:
Property, plant and equipment additions			(298,655)	(290,773)
Proceeds from disposals of property, plant and equipment			42,056	9,247
Increase in restricted cash			0	(9,449)
Investments in consolidated subsidiaries			0	0
Net cash used in investing activities			(256,599)	(290,975)
FINANCING ACTIVITIES:
Repayments of borrowings			0	(139,609)
Advances (to) from affiliates			0	0
Contributions from parent			0	0
Proceeds from borrowings			0	493,415
Dividends paid				0
Excess tax benefits from share-based compensation			157	1,142
Proceeds from exercise of share options			2,180	0
Other			1,820	0
Net cash provided by financing activities			4,157	354,948
(DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS			(18,110)	226,784
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD			1,024,008	438,853
CASH AND CASH EQUIVALENTS, END OF PERIOD	1,005,898	665,637	1,005,898	665,637
Rowan Companies plc (Parent) [Member]
CURRENT ASSETS:
Cash and cash equivalents	62,730	15,975	62,730	15,975
Receivables - trade and other	234		234		107
Other current assets	757		757		293
Assets of discontinued operations	0		0		0
Total current assets	63,721		63,721		59,028
Property, plant and equipment - gross	0		0		0
Less accumulated depreciation and amortization	0		0		0
Property, plant and equipment - net	0		0		0
Investments in subsidiaries	4,652,863		4,652,863		4,562,016
Due from affiliates	446		446		0
Other assets	0		0		0
TOTAL ASSETS	4,717,030		4,717,030		4,621,044
CURRENT LIABILITIES:
Accounts payable - trade	109		109		1,277
Deferred revenues	0		0		0
Accrued liabilities	0		0		0
Liabilities of discontinued operations	0		0		0
Total current liabilities	109		109		1,277
Long-term debt	0		0		0
Due to affiliates	6,359		6,359		88,043
Other liabilities	7,055		7,055		0
Deferred income taxes - net	0		0		0
Shareholders' equity	4,703,507		4,703,507		4,531,724
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	4,717,030		4,717,030		4,621,044
Condensed Consolidating Income Statements [Abstract]
REVENUES	0	0	0	0
COSTS AND EXPENSES:
Direct operating costs (excluding items below)	0	162	0	162
Depreciation and amortization	0	0	0	0
Selling, general and administrative	6,887	4,034	16,099	4,675
Loss (gain) on disposals of property and equipment	0	0	0	0
Material charges and other operating expenses		8,126		9,801
Total costs and expenses	6,887	12,322	16,099	14,638
INCOME (LOSS) FROM OPERATIONS	(6,887)	(12,322)	(16,099)	(14,638)
OTHER INCOME (EXPENSE):
Interest expense, net of interest capitalized	0	0	0	0
Interest income	52	5	94	10
Loss on extinguishment of debt		0		0
Other - net	2,502	2	5,001	2
Total other income (expense) - net	2,554	7	5,095	12
INCOME (LOSS) FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	(4,333)	(12,315)	(11,004)	(14,626)
(Benefit) provision for income taxes	0	0	0	0
NET INCOME FROM CONTINUING OPERATIONS	(4,333)	(12,315)	(11,004)	(14,626)
DISCONTINUED OPERATIONS, NET OF TAX		0		0
EQUITY IN EARNINGS OF SUBSIDIARIES, NET OF TAX	87,177	61,750	161,982	113,578
NET INCOME	82,844	49,435	150,978	98,952
Statement of Comprehensive Income [Abstract]
Net income	82,844	49,435	150,978	98,952
Pension and other postretirement benefit adjustments, net of income taxes
Amortization of net loss	4,447	4,087	8,859	8,174
Amortization of transition obligation		77		154
Amortization of prior service credit	(790)	(776)	(1,574)	(1,551)
OTHER COMPREHENSIVE INCOME	3,657	3,388	7,285	6,777
COMPREHENSIVE INCOME	86,501	52,823	158,263	105,729
Consolidated Statement of Cash Flows [Abstract]
NET CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES			(9,724)	(14,565)
INVESTING ACTIVITIES:
Property, plant and equipment additions			0	0
Proceeds from disposals of property, plant and equipment			0	0
Increase in restricted cash				0
Investments in consolidated subsidiaries			0	0
Net cash used in investing activities			0	0
FINANCING ACTIVITIES:
Repayments of borrowings				0
Advances (to) from affiliates			9,826	9,068
Contributions from parent			0	0
Proceeds from borrowings				0
Dividends paid				0
Excess tax benefits from share-based compensation			0	0
Proceeds from exercise of share options			2,180
Other			1,820
Net cash provided by financing activities			13,826	9,068
(DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS			4,102	(5,497)
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD			58,628	21,472
CASH AND CASH EQUIVALENTS, END OF PERIOD	62,730	15,975	62,730	15,975
RCI (Issuer) [Member]
Condensed Financial Statements, Captions [Line Items]
Ownership interest (in hundredths)	100.00%		100.00%
CURRENT ASSETS:
Cash and cash equivalents	340,202	445,444	340,202	445,444
Receivables - trade and other	106,410		106,410		95,386
Other current assets	61,006		61,006		46,614
Assets of discontinued operations	23,559		23,559		22,954
Total current assets	531,177		531,177		393,039
Property, plant and equipment - gross	1,316,176		1,316,176		1,311,987
Less accumulated depreciation and amortization	497,224		497,224		487,147
Property, plant and equipment - net	818,952		818,952		824,840
Investments in subsidiaries	5,113,475		5,113,475		1,355,968
Due from affiliates	1,749,991		1,749,991		4,524,480
Other assets	36,407		36,407		37,787
TOTAL ASSETS	8,250,002		8,250,002		7,136,114
CURRENT LIABILITIES:
Accounts payable - trade	7,473		7,473		23,210
Deferred revenues	0		0		0
Accrued liabilities	64,131		64,131		73,443
Liabilities of discontinued operations	21,255		21,255		21,255
Total current liabilities	92,859		92,859		117,908
Long-term debt	2,009,152		2,009,152		2,009,598
Due to affiliates	1,111,916		1,111,916		0
Other liabilities	320,288		320,288		323,778
Deferred income taxes - net	103,006		103,006		122,814
Shareholders' equity	4,612,781		4,612,781		4,562,016
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	8,250,002		8,250,002		7,136,114
Condensed Consolidating Income Statements [Abstract]
REVENUES	25,277	39,375	59,636	81,263
COSTS AND EXPENSES:
Direct operating costs (excluding items below)	5,991	7,677	17,309	14,289
Depreciation and amortization	12,635	13,791	25,276	26,673
Selling, general and administrative	1,737	3,881	2,451	9,910
Loss (gain) on disposals of property and equipment	19	1,374	229	1,541
Material charges and other operating expenses		(6)		1,357
Total costs and expenses	20,382	26,717	45,265	53,770
INCOME (LOSS) FROM OPERATIONS	4,895	12,658	14,371	27,493
OTHER INCOME (EXPENSE):
Interest expense, net of interest capitalized	(17,685)	(12,906)	(36,266)	(23,959)
Interest income	160	98	236	141
Loss on extinguishment of debt		(11,180)		(11,180)
Other - net	(2,302)	98	(4,770)	134
Total other income (expense) - net	(19,827)	(23,890)	(40,800)	(34,864)
INCOME (LOSS) FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	(14,932)	(11,232)	(26,429)	(7,371)
(Benefit) provision for income taxes	(9,610)	3,324	(16,998)	5,452
NET INCOME FROM CONTINUING OPERATIONS	(5,322)	(14,556)	(9,431)	(12,823)
DISCONTINUED OPERATIONS, NET OF TAX		(1,413)		(7,395)
EQUITY IN EARNINGS OF SUBSIDIARIES, NET OF TAX	81,083	53,055	131,330	103,441
NET INCOME	75,761	37,086	121,899	83,223
Statement of Comprehensive Income [Abstract]
Net income	75,761	37,086	121,899	83,223
Pension and other postretirement benefit adjustments, net of income taxes
Amortization of net loss	4,447	4,087	8,859	8,174
Amortization of transition obligation		77		154
Amortization of prior service credit	(790)	(776)	(1,574)	(1,551)
OTHER COMPREHENSIVE INCOME	3,657	3,388	7,285	6,777
COMPREHENSIVE INCOME	79,418	40,474	129,184	90,000
Consolidated Statement of Cash Flows [Abstract]
NET CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES			(31,349)	58,243
INVESTING ACTIVITIES:
Property, plant and equipment additions			(31,984)	(20,718)
Proceeds from disposals of property, plant and equipment			2,233	5,653
Increase in restricted cash				(9,449)
Investments in consolidated subsidiaries			(145,791)	(6,669)
Net cash used in investing activities			(175,542)	(31,183)
FINANCING ACTIVITIES:
Repayments of borrowings				(101,602)
Advances (to) from affiliates			318,851	(159,248)
Contributions from parent			0	0
Proceeds from borrowings				493,415
Dividends paid				0
Excess tax benefits from share-based compensation			157	1,142
Proceeds from exercise of share options			0
Other			0
Net cash provided by financing activities			319,008	233,707
(DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS			112,117	260,767
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD			228,085	184,677
CASH AND CASH EQUIVALENTS, END OF PERIOD	340,202	445,444	340,202	445,444
Other non-guarantor subsidiaries [Member]
CURRENT ASSETS:
Cash and cash equivalents	602,966	204,218	602,966	204,218
Receivables - trade and other	363,655		363,655		328,346
Other current assets	25,413		25,413		34,842
Assets of discontinued operations	0		0		0
Total current assets	992,034		992,034		1,100,483
Property, plant and equipment - gross	6,571,689		6,571,689		6,349,106
Less accumulated depreciation and amortization	1,180,488		1,180,488		1,102,217
Property, plant and equipment - net	5,391,201		5,391,201		5,246,889
Due from affiliates	1,111,949		1,111,949		391,008
Other assets	31,301		31,301		37,421
TOTAL ASSETS	7,526,485		7,526,485		6,775,801
CURRENT LIABILITIES:
Accounts payable - trade	70,045		70,045		58,517
Deferred revenues	55,084		55,084		52,340
Accrued liabilities	36,691		36,691		64,052
Liabilities of discontinued operations	0		0		0
Total current liabilities	161,820		161,820		174,909
Long-term debt	0		0		0
Due to affiliates	1,744,111		1,744,111		4,827,445
Other liabilities	74,602		74,602		66,421
Deferred income taxes - net	392,395		392,395		351,058
Shareholders' equity	5,153,557		5,153,557		1,355,968
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	7,526,485		7,526,485		6,775,801
Condensed Consolidating Income Statements [Abstract]
REVENUES	408,087	344,282	799,606	671,057
COSTS AND EXPENSES:
Direct operating costs (excluding items below)	234,534	212,914	464,325	423,627
Depreciation and amortization	53,896	47,539	105,871	93,623
Selling, general and administrative	24,639	17,183	44,144	33,569
Loss (gain) on disposals of property and equipment	(19,241)	(3,437)	(19,143)	(3,660)
Material charges and other operating expenses		6		1,539
Total costs and expenses	293,828	274,205	595,197	548,698
INCOME (LOSS) FROM OPERATIONS	114,259	70,077	204,409	122,359
OTHER INCOME (EXPENSE):
Interest expense, net of interest capitalized	(30)	(87)	(68)	(291)
Interest income	186	43	465	109
Loss on extinguishment of debt		(587)		(587)
Other - net	(643)	(222)	(1,468)	1,079
Total other income (expense) - net	(487)	(853)	(1,071)	310
INCOME (LOSS) FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	113,772	69,224	203,338	122,669
(Benefit) provision for income taxes	21,273	(8,495)	31,925	(11,127)
NET INCOME FROM CONTINUING OPERATIONS	92,499	77,719	171,413	133,796
DISCONTINUED OPERATIONS, NET OF TAX		0		0
EQUITY IN EARNINGS OF SUBSIDIARIES, NET OF TAX	0	0	0	0
NET INCOME	92,499	77,719	171,413	133,796
Statement of Comprehensive Income [Abstract]
Net income	92,499	77,719	171,413	133,796
Pension and other postretirement benefit adjustments, net of income taxes
Amortization of net loss	0	0	0	0
Amortization of transition obligation		0		0
Amortization of prior service credit	0	0	0	0
OTHER COMPREHENSIVE INCOME	0	0	0	0
COMPREHENSIVE INCOME	92,499	77,719	171,413	133,796
Consolidated Statement of Cash Flows [Abstract]
NET CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES			275,405	210,133
INVESTING ACTIVITIES:
Property, plant and equipment additions			(266,671)	(270,055)
Proceeds from disposals of property, plant and equipment			39,823	3,594
Increase in restricted cash				0
Investments in consolidated subsidiaries				0
Net cash used in investing activities			(226,848)	(266,461)
FINANCING ACTIVITIES:
Repayments of borrowings				(38,007)
Advances (to) from affiliates			(328,677)	150,180
Contributions from parent			145,791	6,669
Proceeds from borrowings				0
Dividends paid				(91,000)
Excess tax benefits from share-based compensation			0	0
Proceeds from exercise of share options			0
Other			0
Net cash provided by financing activities			(182,886)	27,842
(DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS			(134,329)	(28,486)
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD			737,295	232,704
CASH AND CASH EQUIVALENTS, END OF PERIOD	602,966	204,218	602,966	204,218
Consolidating adjustments [Member]
CURRENT ASSETS:
Cash and cash equivalents	0	0	0	0
Receivables - trade and other	0		0		0
Other current assets	0		0		0
Assets of discontinued operations	0		0		0
Total current assets	0		0		0
Property, plant and equipment - gross	0		0		0
Less accumulated depreciation and amortization	0		0		0
Property, plant and equipment - net	0		0		0
Investments in subsidiaries	(9,766,338)		(9,766,338)		(5,917,984)
Due from affiliates	(2,862,386)		(2,862,386)		(4,915,488)
Other assets	0		0		0
TOTAL ASSETS	(12,628,724)		(12,628,724)		(10,833,472)
CURRENT LIABILITIES:
Accounts payable - trade	0		0		0
Deferred revenues	0		0		0
Accrued liabilities	0		0		0
Liabilities of discontinued operations	0		0		0
Total current liabilities	0		0		0
Long-term debt	0		0		0
Due to affiliates	(2,862,386)		(2,862,386)		(4,915,488)
Other liabilities	0		0		0
Deferred income taxes - net	0		0		0
Shareholders' equity	(9,766,338)		(9,766,338)		(5,917,984)
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	(12,628,724)		(12,628,724)		(10,833,472)
Condensed Consolidating Income Statements [Abstract]
REVENUES	(24,481)	(32,639)	(56,121)	(67,825)
COSTS AND EXPENSES:
Direct operating costs (excluding items below)	(24,481)	(32,639)	(56,121)	(67,825)
Depreciation and amortization	0	0	0	0
Selling, general and administrative	0	0	0	0
Loss (gain) on disposals of property and equipment	0	0	0	0
Material charges and other operating expenses		0		0
Total costs and expenses	(24,481)	(32,639)	(56,121)	(67,825)
INCOME (LOSS) FROM OPERATIONS	0	0	0	0
OTHER INCOME (EXPENSE):
Interest expense, net of interest capitalized	30	0	68	0
Interest income	(30)	0	(68)	0
Loss on extinguishment of debt		0		0
Other - net	0	0	0	0
Total other income (expense) - net	0	0	0	0
INCOME (LOSS) FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	0	0	0	0
(Benefit) provision for income taxes	0	0	0	0
NET INCOME FROM CONTINUING OPERATIONS	0	0	0	0
DISCONTINUED OPERATIONS, NET OF TAX		0		0
EQUITY IN EARNINGS OF SUBSIDIARIES, NET OF TAX	(168,260)	(114,805)	(293,312)	(217,019)
NET INCOME	(168,260)	(114,805)	(293,312)	(217,019)
Statement of Comprehensive Income [Abstract]
Net income	(168,260)	(114,805)	(293,312)	(217,019)
Pension and other postretirement benefit adjustments, net of income taxes
Amortization of net loss	(4,447)	(4,087)	(8,859)	(8,174)
Amortization of transition obligation		(77)		(154)
Amortization of prior service credit	790	776	1,574	1,551
OTHER COMPREHENSIVE INCOME	(3,657)	(3,388)	(7,285)	(6,777)
COMPREHENSIVE INCOME	(171,917)	(118,193)	(300,597)	(223,796)
Consolidated Statement of Cash Flows [Abstract]
NET CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES			0	(91,000)
INVESTING ACTIVITIES:
Property, plant and equipment additions			0	0
Proceeds from disposals of property, plant and equipment			0	0
Increase in restricted cash				0
Investments in consolidated subsidiaries			145,791	6,669
Net cash used in investing activities			145,791	6,669
FINANCING ACTIVITIES:
Repayments of borrowings				0
Advances (to) from affiliates			0	0
Contributions from parent			(145,791)	(6,669)
Proceeds from borrowings				0
Dividends paid				91,000
Excess tax benefits from share-based compensation			0	0
Proceeds from exercise of share options			0
Other			0
Net cash provided by financing activities			(145,791)	84,331
(DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS			0	0
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD			0	0
CASH AND CASH EQUIVALENTS, END OF PERIOD	$ 0	$ 0	$ 0	$ 0