Supplemental Condensed Consolidating Balance Sheet (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 32,069	$ 17,238	$ 23,471	$ 41,229
Accounts receivable, net	1,282,735	1,116,961
Supplies	108,115	101,781
Deferred income taxes	114,565	119,903
Other current assets	77,654	76,446
Total current assets	1,615,138	1,432,329
Investments in subsidiaries	0	0
Intercompany receivable	0	0
Intercompany note receivable	0	0
Property and equipment	6,212,030	5,691,902
Less: accumulated depreciation	(2,532,341)	(2,249,733)
Property, Plant and Equipment, Net	3,679,689	3,442,169
Other assets:
Goodwill	3,291,213	3,049,016	3,036,765
Deferred charges	40,319	57,881
Other	348,084	330,328
Total assets	8,974,443	8,311,723	8,200,843
Current liabilities:
Current maturities of long-term debt	68,319	99,312
Accounts payable and accrued liabilities	1,113,062	953,449
Federal and state taxes	1,446	7,127
Total current liabilities	1,182,827	1,059,888
Intercompany payable	0	0
Other noncurrent liabilities	268,555	284,589
Long-term debt	3,210,215	3,209,762
Intercompany note payable	0	0
Deferred income taxes	282,214	239,148
Redeemable noncontrolling interests	239,552	218,107
UHS common stockholders' equity	3,735,946	3,249,979
Noncontrolling interest	55,134	50,250
Total equity	3,791,080	3,300,229	2,765,949	2,347,118
Liabilities and Equity, Total	8,974,443	8,311,723
Consolidating Adjustments
Current assets:
Cash and cash equivalents	0	0	0
Accounts receivable, net	0	0
Supplies	0	0
Deferred income taxes	0	0
Other current assets	0	0
Total current assets	0	0
Investments in subsidiaries	(8,674,836)	(7,855,410)
Intercompany receivable	(512,490)	(758,003)
Intercompany note receivable	(1,222,637)	(982,568)
Property and equipment	0	0
Less: accumulated depreciation	0	0
Property, Plant and Equipment, Net	0	0
Other assets:
Goodwill	0	0
Deferred charges	0	0
Other	0	0
Total assets	(10,409,963)	(9,595,981)
Current liabilities:
Current maturities of long-term debt	0	0
Accounts payable and accrued liabilities	0	0
Federal and state taxes	0	0
Total current liabilities	0	0
Intercompany payable	(512,490)	(758,003)
Other noncurrent liabilities	0	0
Long-term debt	0	0
Intercompany note payable	(1,222,637)	(982,568)
Deferred income taxes	0	0
Redeemable noncontrolling interests	0	0
UHS common stockholders' equity	(8,674,836)	(7,855,410)
Noncontrolling interest	0	0
Total equity	(8,674,836)	(7,855,410)
Liabilities and Equity, Total	(10,409,963)	(9,595,981)
Parent
Current assets:
Cash and cash equivalents	0	0	0
Accounts receivable, net	0	0
Supplies	0	0
Deferred income taxes	113,822	76,719
Other current assets	0	0
Total current assets	113,822	76,719
Investments in subsidiaries	7,013,540	6,378,499
Intercompany receivable	103,808	226,592
Intercompany note receivable	0	0
Property and equipment	0	0
Less: accumulated depreciation	0	0
Property, Plant and Equipment, Net	0	0
Other assets:
Goodwill	0	0
Deferred charges	32,379	49,866
Other	9,601	8,411
Total assets	7,273,150	6,740,087
Current liabilities:
Current maturities of long-term debt	44,874	97,403
Accounts payable and accrued liabilities	20,245	28,099
Federal and state taxes	1,446	4,963
Total current liabilities	66,565	130,465
Intercompany payable	0	0
Other noncurrent liabilities	1,322	7,591
Long-term debt	3,187,103	3,168,819
Intercompany note payable	0	0
Deferred income taxes	282,214	183,233
Redeemable noncontrolling interests	0	0
UHS common stockholders' equity	3,735,946	3,249,979
Noncontrolling interest	0	0
Total equity	3,735,946	3,249,979
Liabilities and Equity, Total	7,273,150	6,740,087
Guarantors
Current assets:
Cash and cash equivalents	21,784	7,990	11,949
Accounts receivable, net	933,971	799,898
Supplies	67,847	63,562
Deferred income taxes	743	43,184
Other current assets	62,431	63,786
Total current assets	1,086,776	978,420
Investments in subsidiaries	1,661,296	1,476,911
Intercompany receivable	0	0
Intercompany note receivable	0	0
Property and equipment	4,494,567	4,093,914
Less: accumulated depreciation	(1,686,192)	(1,478,758)
Property, Plant and Equipment, Net	2,808,375	2,615,156
Other assets:
Goodwill	2,764,555	2,552,190
Deferred charges	5,402	5,577
Other	283,302	251,365
Total assets	8,609,706	7,879,619
Current liabilities:
Current maturities of long-term debt	1,260	916
Accounts payable and accrued liabilities	1,051,309	837,354
Federal and state taxes	0	2,164
Total current liabilities	1,052,569	840,434
Intercompany payable	512,490	758,003
Other noncurrent liabilities	189,456	199,104
Long-term debt	20,212	5,337
Intercompany note payable	1,222,637	982,568
Deferred income taxes	0	55,915
Redeemable noncontrolling interests	0	0
UHS common stockholders' equity	5,612,342	5,038,258
Noncontrolling interest	0	0
Total equity	5,612,342	5,038,258
Liabilities and Equity, Total	8,609,706	7,879,619
Non Guarantors
Current assets:
Cash and cash equivalents	10,285	9,248	11,522
Accounts receivable, net	348,764	317,063
Supplies	40,268	38,219
Deferred income taxes	0	0
Other current assets	15,223	12,660
Total current assets	414,540	377,190
Investments in subsidiaries	0	0
Intercompany receivable	408,682	531,411
Intercompany note receivable	1,222,637	982,568
Property and equipment	1,717,463	1,597,988
Less: accumulated depreciation	(846,149)	(770,975)
Property, Plant and Equipment, Net	871,314	827,013
Other assets:
Goodwill	526,658	496,826
Deferred charges	2,538	2,438
Other	55,181	70,552
Total assets	3,501,550	3,287,998
Current liabilities:
Current maturities of long-term debt	22,185	993
Accounts payable and accrued liabilities	41,508	87,996
Federal and state taxes	0	0
Total current liabilities	63,693	88,989
Intercompany payable	0	0
Other noncurrent liabilities	77,777	77,894
Long-term debt	2,900	35,606
Intercompany note payable	0	0
Deferred income taxes	0	0
Redeemable noncontrolling interests	239,552	218,107
UHS common stockholders' equity	3,062,494	2,817,152
Noncontrolling interest	55,134	50,250
Total equity	3,117,628	2,867,402
Liabilities and Equity, Total	$ 3,501,550	$ 3,287,998