Goodwill and Other Intangibles Assets (Tables)

12 Months Ended

Dec. 31, 2012

Goodwill and Other Intangible Assets [Abstract]

Schedule of Goodwill

	Year ended December 31,
	2012		2011
Balance, beginning of year	$	4,264,845	$	4,150,247
Goodwill acquired as part of acquisitions during the year		141,277		114,473
Consideration adjustments and purchase price allocation
adjustments for prior year’s acquisitions		2,016		125
Balance, end of year	$	4,408,138	$	4,264,845