Income Taxes Income Tax Components (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Contingency [Line Items]
Valuation Allowance, Deferred Tax Asset, Change in Amount	$ 10,591	$ 9,420
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount	76,750
Unrecognized Tax Benefits	$ 9,103	$ 4,265
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	35.00%	35.00%	35.00%
Effective Income Tax Rate Reconciliation, Tax Settlement, State and Local, Amount	$ 20,047	$ 39,492	$ (1,436)
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Depletion, Amount	$ (18,960)	$ (29,526)	$ (42,302)