The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 159

-Paragraph 18

-Subparagraph f

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 18

-Paragraph 20

-Subparagraph a (1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Transactions With Related Parties (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended				1 Months Ended		9 Months Ended
	Sep. 30, 2011 Rent On Buildings [Member] Darden Family [Member]	Sep. 30, 2010 Rent On Buildings [Member] Darden Family [Member]	Sep. 30, 2011 Use Of Airplane [Member] Darden Family [Member]	Sep. 30, 2010 Use Of Airplane [Member] Darden Family [Member]	Oct. 31, 2011 Darden Family [Member]	Sep. 30, 2011 Darden Family [Member]	Sep. 30, 2010 Mercury Exploration Company [Member]
Related Party Transaction [Line Items]
Percentage of ownership interest						32.00%
Payments to related parties	$ 0.1	$ 0.7	$ 0.6	$ 0.6
Purchase price of the manufacturing facility					1.1
Payments received for sublease rentals, employee insurance coverage and administrative services							$ 0.3