Income Taxes, Deferred Tax Asset Valuation Adjustments (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019		Dec. 31, 2018		Dec. 31, 2017
Valuation Allowance [Roll Forward]
Recognition of valuation allowance on foreign tax credit carryforwards		$ 9,800		$ 27,200		$ 52,000
Deferred Tax Asset Valuation Allowance [Member]
Valuation Allowance [Roll Forward]
Beginning balance		68,697		56,906		9,137
Additions charged to cost and expenses		10,913	[1]	27,902	[2]	53,983	[3]
Decreases		(3,343)	[4]	(16,215)	[5]	(6,400)	[6]
Adjustments	[7]	775		104		186
Ending balance		$ 77,042		$ 68,697		$ 56,906

[1] Increase in valuation is due primarily to $9.8 million that was recorded on the foreign tax credit carryforward. The additional amount is due to net operating losses in foreign markets.

[2] Increase in valuation is due primarily to the $27.2 million that was recorded on the foreign tax credit carryforward. The additional amount is due to net operating losses in foreign markets

[3] Increase in valuation allowance is due primarily to the $52.0 million that was recorded on the foreign tax credit carryforward. The additional amount is due to net operating losses in foreign markets.

[4] The decrease was due primarily to the utilization of foreign tax credits, and expiration of foreign net operating losses.

[5] The decrease was due primarily to the utilization of foreign tax credits. Decrease is due primarily to the write-off of Brazil deferred tax assets, which had no impact to the income statement, as a valuation allowance had been previously recorded against the asset.

[6] Decrease is due primarily to the write-off of Brazil deferred tax assets, which had no impact to the income statement, as a valuation allowance had been previously recorded against the asset.

[7] Represents the net currency effects of translating valuation allowances at current rates of exchange.