CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 109,375	$ 135,227
Short-term investments	21,460
Accounts receivable, net of allowance for doubtful accounts of $1,172 and $830, respectively and estimated allowance for appeals of $12,518 and $6,985 at September 30, 2013 and December 31, 2012, respectively	168,011	153,014
Prepaid expenses	13,108	14,283
Prepaid income taxes	994
Current portion of deferred financing costs		3,336
Other current assets	406	317
Total current assets	313,354	306,177
Property and equipment, net	126,093	129,327
Goodwill	361,468	361,468
Intangible assets, net	100,502	119,119
Deferred financing costs	9,562	5,867
Other assets	4,472	3,988
Total assets	915,451	925,946
Current liabilities:
Accounts payable, accrued expenses and other liabilities	45,426	40,867
Acquisition related contingent consideration	435	425
Current portion of term loan		35,000
Deferred tax liabilities	2,310	2,398
Estimated liability for appeals	27,484	21,787
Total current liabilities	75,655	100,477
Long-term liabilities:
Deferred rent	754	500
Acquisition related contingent consideration	498	485
Revolving debt	267,796
Term loan		297,500
Other liabilities	4,469	3,305
Deferred tax liabilities	54,715	60,805
Total long-term liabilities	328,232	362,595
Total liabilities	403,887	463,072
Shareholders' equity:
Preferred stock - $0.01 par value; 5,000,000 shares authorized; none issued
Common stock - $0.01 par value; 125,000,000 shares authorized; 93,358,890 shares issued and 87,934,043, shares outstanding at September 30, 2013; 92,374,539 shares issued and 86,949,692 shares outstanding at December 31, 2012	932	923
Capital in excess of par value	291,739	271,962
Retained earnings	238,907	210,003
Treasury stock, at cost: 5,424,847 shares at September 30, 2013 and at December 31, 2012	(20,014)	(20,014)
Total shareholders' equity	511,564	462,874
Total liabilities and shareholders' equity	$ 915,451	$ 925,946