Income Taxes Federal Tax Reform (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Federal Tax Reform
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent		35.00%	35.00%
Percentage of Net Operating Losses Limited upon Tax Reform Enactment		80.00%
Reevaluation of Deferred Income Taxes due to tax reform		$ 98,500
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount		$ (14,299)	$ 0	$ 0
Federal tax reform [Member]
Federal Tax Reform
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%