Income Taxes Unrecognized Tax Benefits Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Contingency [Line Items]
Unrecognized Tax Benefits	$ 3,020	$ 3,370	$ 3,570
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	2,500	2,800
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	$ 1,800	$ 1,700
Minimum [Member]
Income Tax Contingency [Line Items]
Open Tax Year	2018
Maximum [Member]
Income Tax Contingency [Line Items]
Open Tax Year	2011