Income Taxes (Details 1)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation of federal statutory tax rate with effective tax rate
Federal statutory tax rate	35.00%	35.00%	35.00%
Impact on deferred taxes for changes in tax rates	(0.90%)	0.10%	0.00%
State income taxes, net of federal income tax benefit	5.20%	4.00%	4.10%
Foreign rates varying from federal	(3.70%)	(4.10%)	(2.80%)
Tax reviews and audits	(1.10%)	(0.80%)	(2.70%)
Miscellaneous items, net	0.40%	(0.10%)	0.10%
Effective tax rate	34.90%	34.10%	33.70%