Income Taxes (Schedule of Net Deferred Tax Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Income Taxes [Abstract]
Net operating loss and tax credit carryforwards	$ 119,524	$ 117,676
Compensation and benefits	1,582	1,639
Indemnification liabilities	1,346	5,434
Other, net	219	2,023
Federal benefit of uncertain tax positions	7,528	7,818
Pension costs	5,984	6,294
Investments in and advances to affiliates		20,004
Total deferred tax assets before valuation allowance	136,183	160,888
Less valuation allowance	(3,647)	(8,212)
Deferred tax assets net of valuation allowance	132,536	152,676
Investments in and advances to affiliates	17,257
Total deferred tax liabilities	17,257
Long-term deferred tax assets	115,285	152,676
Long-term liabilities	(6)
Net deferred tax assets	$ 115,279	$ 152,676