Earnings Per Share (Schedule of Earnings Per Share, Basic And Diluted) (Details) - USD ($)		3 Months Ended		6 Months Ended		12 Months Ended
	Dec. 05, 2014	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Numerators [Abstract]
Numerator for both basic and diluted EPS, net income		$ 74,558,437	$ 76,726,746	$ 151,741,878	$ 145,292,817
Denominators [Abstract]
Denominator for basic EPS, weighted-average shares outstanding		293,958,258	290,430,260	294,461,499	290,119,368
Potentially dilutive shares resulting from stock plans		3,503,844	2,568,726	3,528,533	3,117,810
Denominator for diluted EPS		297,462,102	292,998,986	297,990,032	293,237,178
Shares related to stock plans not included in diluted average common shares outstanding because their effect would be anti-dilutive		1,804,157	5,989,258	1,496,107	1,990,354
Common Stock
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Stock split, conversion ratio	2					2
Stock split, stock dividend	100.00%					100.00%