Commitments and Contingencies (Details) Fish Springs Ranch (Fish Springs Ranch, LLC, USD $) In Millions, unless otherwise specified	1 Months Ended
Sep. 30, 2007	Dec. 31, 2012
Fish Springs Ranch, LLC
Loss Contingencies [Line Items]
Litigation settlement	$ 7.3
Payments for litigation settlements	3.7
Accrual for remaining litigation settlement		$ 3.6

The carrying amount as of the balance sheet date of the combined total of loss contingency liabilities.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 5

-Paragraph 9, 10, 11, 12

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6952336&loc=d3e14326-108349

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