Debt (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Debt
Gross interest cost	$ 6,298	$ 2,028	$ 10,728	$ 2,398
Capitalized interest	(2,410)	(2,028)	(5,338)	(2,028)
Interest expense	$ 3,888		$ 5,390	$ 370