Nature Of Operations And Accounting Policies (Schedule of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Total equity, beginning balance	$ 753,361	$ 1,196,268	$ 1,390,939
Discontinued Operations		(527,691)
Other comprehensive income (loss)	(391)	1,707	(10,183)
Income tax (expense) benefit	22	(702)	3,174
Total equity, ending balance	853,842	753,361	1,196,268
Foreign Currency Translation Adjustments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Total equity, beginning balance	(545)	(11,593)	(5,528)
Discontinued Operations		10,031
Other comprehensive income (loss)	(391)	1,812	(9,331)
Income tax (expense) benefit	22	(795)	3,266
Total equity, ending balance	(914)	(545)	(11,593)
Derivative Losses on Cash Flow Hedges, net
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Total equity, beginning balance	0	75	(116)
Discontinued Operations		94
Other comprehensive income (loss)	0	(260)	294
Income tax (expense) benefit	0	91	(103)
Total equity, ending balance	0	0	75
Other
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Total equity, beginning balance	0	4	24
Discontinued Operations		0
Other comprehensive income (loss)	0	(6)	(31)
Income tax (expense) benefit	0	2	11
Total equity, ending balance	0	0	4
Accumulated Other Comprehensive Loss
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Total equity, beginning balance	(545)	(11,514)	(5,620)
Discontinued Operations		10,125
Other comprehensive income (loss)	(391)	1,546	(9,068)
Income tax (expense) benefit	22	(702)	3,174
Total equity, ending balance	(914)	(545)	(11,514)
Foreign Currency Translation Adjustments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Total equity, beginning balance	0	(1,613)	(528)
Discontinued Operations		1,460
Other comprehensive income (loss)	0	153	(1,085)
Income tax (expense) benefit	0	0	0
Total equity, ending balance	0	0	(1,613)
Derivative Losses on Cash Flow Hedges, net
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Total equity, beginning balance	0	(17)	0
Discontinued Operations		4
Other comprehensive income (loss)	0	13	(17)
Income tax (expense) benefit	0	0	0
Total equity, ending balance	0	0	(17)
Other
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Total equity, beginning balance	0	3	16
Discontinued Operations		2
Other comprehensive income (loss)	0	(5)	(13)
Income tax (expense) benefit	0	0	0
Total equity, ending balance	0	0	3
Other Comprehensive Income (Loss)
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Total equity, beginning balance	1,005	(7,009)
Total equity, ending balance	$ (369)	$ 1,005	$ (7,009)