Income Taxes:	6 Months Ended
Jun. 30, 2016
Income Tax Disclosure [Abstract]
Income Tax Disclosure [Text Block]	Income Taxes Income taxes were accrued at an estimated effective tax rate of 28% and 27% for the six months ended June 30, 2016 and 2015, respectively. Those rates differ from that computed at the federal statutory rate of 35%. The effective tax rate for the six months ended June 30, 2016 differs from 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 included material discrete tax benefits related to the adoption of ASU 2016-09, see below. The effective tax rate during the six months ended June 30, 2016 included a material tax benefit of $3.1 million related to the early adoption of ASU 2016-09, Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting, which amends current accounting to now recognize all excess tax benefits and all tax deficiencies as income tax benefit or expense in the reporting period in which they occur. The income tax benefit was treated as a discrete item when determining the annual estimated effective tax rate see Note 2, New Accounting Pronouncements for further detail. The effective tax rate for the six months ended June 30, 2015 differs from the federal statutory rate 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:

6 Months Ended

Jun. 30, 2016

Income Taxes

Income taxes were accrued at an estimated effective tax rate of 28% and 27% for the six months ended June 30, 2016 and 2015, respectively. Those rates differ from that computed at the federal statutory rate of 35%.

The effective tax rate for the six months ended June 30, 2016 differs from 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 included material discrete tax benefits related to the adoption of ASU 2016-09, see below.

The effective tax rate during the six months ended June 30, 2016 included a material tax benefit of $3.1 million related to the early adoption of ASU 2016-09, Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting, which amends current accounting to now recognize all excess tax benefits and all tax deficiencies as income tax benefit or expense in the reporting period in which they occur. The income tax benefit was treated as a discrete item when determining the annual estimated effective tax rate see Note 2, New Accounting Pronouncements for further detail.

The effective tax rate for the six months ended June 30, 2015 differs from the federal statutory rate 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.