Significant Accounting Policies Capitalized Costs (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Intangible assets useful life			12 months
Interest costs capitalized	$ 1,200,000	$ 790,000	$ 2,200,000	$ 1,300,000
Payroll costs capitalized	860,000	750,000	1,600,000	1,300,000
Number of properties classified as held for sale	0		0		0
Amount adjusted			$ 8,300,000