Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2011

Rent Expense on Operating Leases

	2011		2010		2009
Rent expense	$	308,561	$	276,030	$	300,609
Sublease proceeds		(4,700)		(7,090)		(6,114)
Net rent expense	$	303,861	$	268,940	$	294,495

Future Operating Lease Commitments

2012	$	254,888
2013		215,187
2014		170,408
2015		129,099
2016		90,048
Thereafter		641,413
Total minimum lease payments	$	1,501,043

Expected Future Non-cancelable Sublease Proceeds

2012	$	3,250
2013		1,602
2014		1,607
2015		1,616
2016		1,276
Thereafter		3,159
Total sublease proceeds	$	12,510