Income Taxes - Reconciliation of Income Tax Provision to Statutory Federal Tax Rate (Details)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]
Statutory federal tax rate	35.00%	35.00%	35.00%
State taxes, net of federal taxes	1.60%	1.30%	0.70%
Resolution of uncertain tax positions	(0.90%)	(0.50%)	(1.70%)
Tax rate differential for international jurisdictions and other international related tax items	(15.20%)	(13.60%)	(14.40%)
U.S. tax credits	(3.80%)	(0.20%)	(2.80%)
International reorganization of acquired companies	0.60%	0.30%	0.00%
Permanent items	2.30%	1.50%	2.50%
Other	0.40%	0.30%	0.40%
Effective income tax rate	20.00%	24.10%	19.70%