Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2018
Operating Loss Carryforwards [Line Items]
Additions for tax positions related to current year	$ 0	$ 88
Effective income tax rate	1.46%		0.44%
Income Tax Benefit (Expense) Discrete Items	$ 5,320
Income tax expense	(217)	$ 1,679	$ (297)	$ 6,027
Income Tax Expense (Benefit), before discrete items	$ (947)		$ (5,030)
Effective Income Tax Rate Reconciliation, Excluding Discrete Items, Percent	(6.38%)		(7.38%)
Unrecognized Tax Benefits	$ 9,300		$ 9,300			$ 9,294
Unrecognized tax benefits, period increase (decrease)			$ 0	$ (88)
Minimum [Member] | Scenario, Forecast
Operating Loss Carryforwards [Line Items]
Effective income tax rate					6.00%
Maximum [Member] | Scenario, Forecast
Operating Loss Carryforwards [Line Items]
Effective income tax rate					7.00%