Share Repurchase Program (Tables)

9 Months Ended

Sep. 30, 2016

Proceeds from (Repurchase of) Equity [Abstract]

Schedule of shares repurchased

	For the Three Months Ended   September 30,				For the Nine Months Ended   September 30,
	2016		2015		2016		2015
Shares repurchased	367		1,147		3,673		3,784
Average price per share	$	281.04	$	238.97	$	261.32	$	224.39
Total investment	$	102,941	$	274,213	$	959,743	$	849,145