Related Party Transactions Related Party Operating Expenses (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Related Party Transaction [Line Items]
General and Administrative—Related Party	$ 2,651	$ 2,858
Property lease expense [Member]
Related Party Transaction [Line Items]
General and Administrative—Related Party	1,198	1,220
Restricted stock compensation expense [Member]
Related Party Transaction [Line Items]
General and Administrative—Related Party	310	465
Aircraft Operating and Lease Expense [Member]
Related Party Transaction [Line Items]
General and Administrative—Related Party	1,088	1,016
Salaries and wages, general & administrative and other expenses
Related Party Transaction [Line Items]
General and Administrative—Related Party	132	228
Reimbursement of certain general and administrative expenses
Related Party Transaction [Line Items]
General and Administrative—Related Party	$ (77)	$ (71)