Stock-Based Compensation (Narrative) (Details) (USD $)	3 Months Ended				6 Months Ended				3 Months Ended		6 Months Ended			1 Months Ended		3 Months Ended	6 Months Ended			6 Months Ended		3 Months Ended		6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012		Jun. 30, 2013		Jun. 30, 2012 installment		Jun. 30, 2013 Employee Stock Option [Member]	Jun. 30, 2012 Employee Stock Option [Member]	Jun. 30, 2013 Employee Stock Option [Member]	Jun. 30, 2012 Employee Stock Option [Member]	Jun. 30, 2013 Non-Vested Stock Unit Awards [Member]	Mar. 31, 2013 Market and Service Condition Stock Units [Member]	Mar. 31, 2012 Market and Service Condition Stock Units [Member]	Jun. 30, 2013 Market and Service Condition Stock Units [Member]	Jun. 30, 2013 Market and Service Condition Stock Units [Member]	Jun. 30, 2012 Market and Service Condition Stock Units [Member]	Jun. 30, 2013 2005 Plan [Member]	Jun. 30, 2013 2005 Plan [Member] Minimum [Member]	Jun. 30, 2013 2005 Plan [Member] Maximum [Member]	Jun. 30, 2013 2005 ESPP Plan [Member]	Jun. 30, 2012 2005 ESPP Plan [Member]	Jun. 30, 2013 2005 ESPP Plan [Member] frequency	Jun. 30, 2012 2005 ESPP Plan [Member]	Jun. 30, 2013 2005 ESPP Plan [Member] Minimum [Member]	Jun. 30, 2013 2005 ESPP Plan [Member] Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance under 2005 Equity Incentive Plan																			48,600,000			10,000,000		10,000,000
Ownership percentage of company where incentive stock options must be granted with an exercise price greater than fair market value																					10.00%
Exercise price of incentive stock options granted to individuals owning 10% or more of the Company's common stock, as a percentage of fair market value of common stock on the date of grant																				110.00%
Shares reserved for issuance under the 2005 Equity Incentive Plan																			28,497,205
Shares available for grant under the 2005 Equity Incentive Plan																			16,942,711
Employee Stock Purchase Plan, maximum purchase frequency per year																								2
Employee Stock Purchase Plan, payment period																								6 months
Employee Stock Purchase Plan, minimum payroll deduction 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																						2,779,821		2,779,821
stock-based compensation cost	$ 47,857,000	[1]	$ 38,262,000	[1]	$ 91,413,000	[1]	$ 68,819,000	[1]														$ 1,200,000	$ 900,000	$ 2,600,000	$ 1,900,000
Stock options vesting life assumed											5 years
Stock option vesting period											3 years
Stock-based compensation award vesting period, percentage of award vesting each year											33.30%		33.33%
Stock-based compensation award vesting period, percentage of award vesting each month											2.78%
Vesting period of options from acquisitions											3 years
The weighted average fair value per share of stock options granted									$ 27.57
The total intrinsic value of options exercised									11,000,000	38,000,000	41,500,000	77,200,000
Total unrecognized compensation cost	54,900,000				54,900,000
Total unrecognized compensation cost recognition period					1 year 6 months 15 days								2 years 1 month 40 days
Non-vested stock unit awards granted to senior level employees														399,029	418,809
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%
The estimated fair value of each award																	$ 89.93	$ 89.95
Stock-based compensation award vesting period, percent vested on third anniversary of grant date													100.00%
Stock-based compensation award vesting period, number of monthly installments							12
Share based awards granted and outstanding													4,592,398
Total unrecognized compensation cost related to stock-based compensation													$ 281,200,000

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