Stock-Based Compensation and Equity (Narratives) (Details) (USD $)	12 Months Ended						3 Months Ended		1 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended															12 Months Ended			0 Months Ended	12 Months Ended					12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Deferred Profit Sharing	Dec. 31, 2012 Deferred Profit Sharing	Dec. 31, 2011 Deferred Profit Sharing	Mar. 31, 2013 2009 Share Incentive Plan	Dec. 31, 2013 2009 Share Incentive Plan	Jul. 31, 2013 2009 Non-Employee Directors Plan	Mar. 31, 2013 2009 Non-Employee Directors Plan	Dec. 31, 2013 2009 Non-Employee Directors Plan	Mar. 31, 2013 Incentive Plan One	Dec. 31, 2013 Incentive Plan One	Dec. 31, 2013 Incentive Plan Four	Dec. 31, 2013 Restricted Stock And Units RSU [Member]	Dec. 31, 2012 Restricted Stock And Units RSU [Member]	Dec. 31, 2011 Restricted Stock And Units RSU [Member]	Dec. 31, 2013 Restricted Stock And Units RSU [Member] 2009 Share Incentive Plan	Dec. 31, 2012 Restricted Stock And Units RSU [Member] 2009 Share Incentive Plan	Dec. 31, 2011 Restricted Stock And Units RSU [Member] 2009 Share Incentive Plan	Dec. 31, 2013 Performance Stock Units	Dec. 31, 2012 Performance Stock Units	Dec. 31, 2011 Performance Stock Units	Dec. 31, 2013 Performance Stock Units 2009 Share Incentive Plan	Dec. 31, 2012 Performance Stock Units 2009 Share Incentive Plan	Dec. 31, 2011 Performance Stock Units 2009 Share Incentive Plan	Dec. 31, 2013 Restricted Stock Units	Dec. 31, 2013 Employee Stock	Dec. 31, 2012 Employee Stock	Dec. 31, 2011 Employee Stock	Dec. 16, 2013 Partnership Equity Plan	Dec. 31, 2013 Partnership Equity Plan	Dec. 31, 2012 Partnership Equity Plan	Dec. 31, 2013 Restricted Stock Awards	Dec. 31, 2013 Long Term Incentive Plan	Dec. 31, 2012 Long Term Incentive Plan	Dec. 31, 2013 Employment agreements Restricted Stock And Units RSU [Member] 2009 Share Incentive Plan	Dec. 31, 2012 Employment agreements Restricted Stock And Units RSU [Member] 2009 Share Incentive Plan	Dec. 31, 2011 Employment agreements Restricted Stock And Units RSU [Member] 2009 Share Incentive Plan	Dec. 31, 2013 Employment agreements Performance Stock Units 2009 Share Incentive Plan	Dec. 31, 2012 Employment agreements Performance Stock Units 2009 Share Incentive Plan	Dec. 31, 2011 Employment agreements Performance Stock Units 2009 Share Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted in period															185,015	274,420	541,890	171,804	259,400	524,550	86,189	314,400	291,600	85,900	314,400	291,600											20,250	78,000	340,000	10,000	142,000	100,000
Stock-Based and Other Compensation Additional Disclosures
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	$ 18,400,000	$ 16,200,000	$ 7,800,000
Shares authorized for grant								5,900,000			325,000
Share based incentive plan shares issued, shares									13,211
Share based incentive plan shares issued, value									900,000
Shares available for grant								3,977,040			231,864
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate																												10.00%
Maximum percentage of annual contribution allowed to employees	15.00%
Maximum annual contributions per employee, amount	100,000
Share based compensation, effective share purchase price for participants																												85.00%
Stock options required to be issued																																47,126	53,743		363,052	243,262
Payment of Deferred Compensation																															200,000
Deferred compensation obligation	(11,354,000)	(8,358,000)																														1,200,000	1,400,000		10,100,000	7,000,000
Stock-based compensation expenses	37,280,000	26,241,000	17,750,000																									1,200,000	600,000	600,000
Deferred compensation																																700,000	700,000
Exercised - shares	169,412	410,331	449,660
Options exercised during the period, aggeregate instrinsic value	5,700,000	9,300,000	4,600,000
Proceeds from stock plans																												2,300,000	6,800,000	1,200,000
Fair value of vested stock	21,400,000	14,300,000	6,900,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period											1 year		4 years	3 years							3 years											2 years
Risk free interest rate	0.37%
Fair value assumptions expected volatility rate	25.36%
Fair value assumptions expected volatility rate peer index	24.83%
Fair value assumptions expected dividend rate	0.00%
Unrecognized stock based compensation expense																					17,000,000						13,600,000							400,000
Weighted-average remaining term	1 year 1 month 17 days
Profit sharing expense				4,500,000	4,400,000	3,800,000
Severance Costs	$ 700,000	$ 1,100,000	$ 400,000
Share-based award description							The 2009 Incentive Plan provides for the grant of (i) share options, (ii) RSUs, (iii) PSUs, and (iv) dividend equivalent rights. The vesting of grants under both plans is accelerated upon a change in our control and under certain other conditions.			In the discretion of our board of directors, the awards may be in the form of RSUs, share options or RSAs, or any combination of the permitted awards.		These RSAs are scheduled to vest one year from the date of grant.
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period													10 years	10 years