Transactions With Related Parties Transactions With Related Parties (Schedule of Amount Received in Public and Private Partnerships) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Related Party Transaction [Line Items]
Contract drilling	$ 0	$ 0	$ 4
Well supervision and other fees	254	423	435
General and administrative expense reimbursement	$ 6	$ 18	$ 39