Stock-Based Compensation (Narrative) (Details) (USD $)	3 Months Ended				6 Months Ended				3 Months Ended		6 Months Ended		1 Months Ended		6 Months Ended	1 Months Ended		6 Months Ended								3 Months Ended		6 Months Ended
	Jun. 30, 2014 plan		Jun. 30, 2013		Jun. 30, 2014 plan		Jun. 30, 2013		Jun. 30, 2014 Stock Options [Member]	Jun. 30, 2013 Stock Options [Member]	Jun. 30, 2014 Stock Options [Member]	Jun. 30, 2013 Stock Options [Member]	Mar. 31, 2014 Market and Service Condition Stock Units [Member]	Mar. 31, 2013 Market and Service Condition Stock Units [Member]	Jun. 30, 2014 Market and Service Condition Stock Units [Member]	Mar. 31, 2014 Non-vested Stock Units [Member]	Mar. 31, 2013 Non-vested Stock Units [Member]	Jun. 30, 2014 Non-vested Stock Units [Member]	Jun. 30, 2013 Non-vested Stock Units [Member] installment	Jun. 30, 2014 Vesting on first anniversary of date of grant [Member] Stock Options [Member]	Jun. 30, 2014 Vesting in equal monthly installments after first anniversary of date of grant [Member] Stock Options [Member]	Jun. 30, 2014 Annual vesting on each anniversary [Member] Non-vested Stock Units [Member]	Jun. 30, 2014 Vesting on third anniversary [Member] Non-vested Stock Units [Member]	Jun. 30, 2014 Minimum [Member] Market and Service Condition Stock Units [Member]	Jun. 30, 2014 2005 Plan [Member]	Jun. 30, 2014 2005 ESPP Plan [Member]	Jun. 30, 2013 2005 ESPP Plan [Member]	Jun. 30, 2014 2005 ESPP Plan [Member]	Jun. 30, 2013 2005 ESPP Plan [Member]	Jun. 30, 2014 2005 ESPP Plan [Member] Minimum [Member]	Jun. 30, 2014 2005 ESPP Plan [Member] Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock-based compensation plans offered	2				2
Shares authorized for issuance under 2005 Equity Incentive Plan																									29,000,000	10,000,000		10,000,000
Shares reserved for issuance under the 2005 Equity Incentive Plan																									38,858,629
Shares available for grant under the 2005 Equity Incentive Plan																									28,887,392
Employee Stock Purchase Plan, payment period																												6 months
Employee Stock Purchase Plan, option to purchase shares through payroll deduction, payroll deduction amount per pay period per employee, as a percentage of base pay																														1.00%	10.00%
Employee Stock Purchase Plan, maximum number of shares per period that employees can purchase																												12,000
Employee Stock Purchase Plan, purchase price as a percentage of fair market value																												85.00%
Employee Stock Purchase Plan, employee disqualification, ownership percent of outstanding stock																														5.00%
Employee Stock Purchase Plan, total shares issued under plan																										3,305,371		3,305,371
stock-based compensation cost	$ 45,290,000	[1]	$ 47,857,000	[1]	$ 85,991,000	[1]	$ 91,413,000	[1]																		$ 1,300,000	$ 1,200,000	$ 2,700,000	$ 2,600,000
Stock options vesting life assumed											5 years
Stock option vesting period											3 years
Award vesting percentage																				33.30%	2.78%	33.33%	100.00%
Vesting period of options from acquisitions											3 years
The total intrinsic value of options exercised									7,200,000	11,000,000	20,100,000	41,500,000
Total unrecognized compensation cost									9,000,000		9,000,000
Total unrecognized compensation cost recognition period											0 years 11 months 28 days							2 years 0 months 11 days
Non-vested stock unit awards granted to senior level employees													378,022	399,029
Period to determine actual stock grant following end of performance period													60 days
Performance period for grants													3 years
Maximum percentage of market and service condition stock units that will ultimately vest															200.00%
Percentage that Company's return exceeds indexed return																								40.00%
Percentage that Company's return underperforms index																								20.00%
Percent of award issued if return is negative but index is met															75.00%
Number of shares represented by each non-vested stock unit upon vesting																		1
The estimated fair value of each award (in dollars per share)																$ 56.94	$ 89.93
Stock-based compensation award vesting period, number of monthly installments																			12
Share based awards granted and outstanding																		5,196,486
Total unrecognized compensation cost related to stock-based compensation																		$ 260,800,000

[1] Represents expenses presented to management on a consolidated basis only and not allocated to the operating segments.