Income Taxes:	3 Months Ended
Mar. 31, 2016
Income Tax Disclosure [Abstract]
Income Tax Disclosure [Text Block]	Income Taxes Income taxes were accrued at an estimated effective tax rate of 34% and 16% in the first three months of 2016 and 2015, respectively. The March 31, 2015 effective tax rate differs from that computed at the federal statutory rate of 35% principally because of the effect of foreign and state income taxes, tax credits, deductions for domestic production activities and material discrete tax benefits related to the impact of changes in estimates of tax reserves related to uncertainties in income taxes as a result of the favorable conclusion of recent federal and state examinations.

Income Taxes:

3 Months Ended

Mar. 31, 2016

Income Taxes

Income taxes were accrued at an estimated effective tax rate of 34% and 16% in the first three months of 2016 and 2015, respectively. The March 31, 2015 effective tax rate differs from that computed at the federal statutory rate of 35% principally because of the effect of foreign and state income taxes, tax credits, deductions for domestic production activities and material discrete tax benefits related to the impact of changes in estimates of tax reserves related to uncertainties in income taxes as a result of the favorable conclusion of recent federal and state examinations.