Information about Noble-Cayman - Guarantor Obligations (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2014
Guarantor Obligations [Line Items]
Senior notes, maturity date	2016
3.45% Senior Notes due August 2015 [Member]
Guarantor Obligations [Line Items]
Interest rate on the notes	3.45%
3.45% Senior Notes due August 2015 [Member] | Noble-Cayman [Member]
Guarantor Obligations [Line Items]
Outstanding principal balance	$ 350
Interest rate on the notes	3.45%
Senior notes, maturity date	2015
3.05% Senior Notes due March 2016 [Member]
Guarantor Obligations [Line Items]
Interest rate on the notes	3.05%
3.05% Senior Notes due March 2016 [Member] | Noble-Cayman [Member]
Guarantor Obligations [Line Items]
Outstanding principal balance	300
Interest rate on the notes	3.05%
Senior notes, maturity date	2016
2.50% Senior Notes due March 2017 [Member]
Guarantor Obligations [Line Items]
Interest rate on the notes	2.50%
2.50% Senior Notes due March 2017 [Member] | Noble-Cayman [Member]
Guarantor Obligations [Line Items]
Outstanding principal balance	300
Interest rate on the notes	2.50%
Senior notes, maturity date	2017
7.50% Senior Notes due March 2019 [Member]
Guarantor Obligations [Line Items]
Interest rate on the notes	7.50%
7.50% Senior Notes due March 2019 [Member] | Noble-Cayman [Member]
Guarantor Obligations [Line Items]
Outstanding principal balance	202
Interest rate on the notes	7.50%
Senior notes, maturity date	2019
4.90% Senior Notes due August 2020 [Member]
Guarantor Obligations [Line Items]
Interest rate on the notes	4.90%
4.90% Senior Notes due August 2020 [Member] | Noble-Cayman [Member]
Guarantor Obligations [Line Items]
Outstanding principal balance	500
Interest rate on the notes	4.90%
Senior notes, maturity date	2020
4.625% Senior Notes due March 2021 [Member]
Guarantor Obligations [Line Items]
Interest rate on the notes	4.625%
4.625% Senior Notes due March 2021 [Member] | Noble-Cayman [Member]
Guarantor Obligations [Line Items]
Outstanding principal balance	400
Interest rate on the notes	4.625%
Senior notes, maturity date	2021
3.95% Senior Notes due March 2022 [Member]
Guarantor Obligations [Line Items]
Interest rate on the notes	3.95%
3.95% Senior Notes due March 2022 [Member] | Noble-Cayman [Member]
Guarantor Obligations [Line Items]
Outstanding principal balance	400
Interest rate on the notes	3.95%
Senior notes, maturity date	2022
6.20% Senior Notes due August 2040 [Member]
Guarantor Obligations [Line Items]
Interest rate on the notes	6.20%
6.20% Senior Notes due August 2040 [Member] | Noble-Cayman [Member]
Guarantor Obligations [Line Items]
Outstanding principal balance	400
Interest rate on the notes	6.20%
Senior notes, maturity date	2040
6.05% Senior Notes due March 2041 [Member]
Guarantor Obligations [Line Items]
Interest rate on the notes	6.05%
6.05% Senior Notes due March 2041 [Member] | Noble-Cayman [Member]
Guarantor Obligations [Line Items]
Outstanding principal balance	400
Interest rate on the notes	6.05%
Senior notes, maturity date	2041
5.25% Senior Notes due March 2042 [Member]
Guarantor Obligations [Line Items]
Interest rate on the notes	5.25%
5.25% Senior Notes due March 2042 [Member] | Noble-Cayman [Member]
Guarantor Obligations [Line Items]
Outstanding principal balance	$ 500
Interest rate on the notes	5.25%
Senior notes, maturity date	2042