Supplemental Condensed Consolidating Balance Sheet (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 39,523	$ 32,069	$ 39,711	$ 17,238
Accounts receivable, net	1,328,300	1,282,735
Supplies	112,718	108,115
Deferred income taxes	134,554	114,565
Other current assets	81,459	77,654
Total current assets	1,696,554	1,615,138
Investments in subsidiaries	0	0
Intercompany receivable	0	0
Intercompany note receivable	0	0
Property and equipment	6,515,914	6,212,030
Less: accumulated depreciation	(2,739,822)	(2,532,341)
Property, plant and equipment, net, Total	3,776,092	3,679,689
Other assets:
Goodwill	3,388,378	3,291,213
Deferred charges	35,113	40,319
Other	310,741	348,084
Total assets	9,206,878	8,974,443	8,961,592
Current liabilities:
Current maturities of long-term debt	84,883	68,319
Accounts payable and accrued liabilities	1,102,616	1,113,062
Federal and state taxes	8,697	1,446
Total current liabilities	1,196,196	1,182,827
Intercompany payable	0	0
Intercompany note payable	0	0
Other noncurrent liabilities	292,441	268,555
Long-term debt	3,009,954	3,210,215
Deferred income taxes	264,358	282,214
Redeemable noncontrolling interests	250,213	239,552
Equity:
UHS common stockholders’ equity	4,133,099	3,735,946
Noncontrolling interest	60,617	55,134
Total equity	4,193,716	3,791,080
Liabilities and Equity, Total	9,206,878	8,974,443
Parent
Current assets:
Cash and cash equivalents	0	0	0	0
Accounts receivable, net	0	0
Supplies	0	0
Deferred income taxes	132,407	113,822
Other current assets	0	0
Total current assets	132,407	113,822
Investments in subsidiaries	7,569,657	7,013,540
Intercompany receivable	0	103,808
Intercompany note receivable	0	0
Property and equipment	0	0
Less: accumulated depreciation	0	0
Property, plant and equipment, net, Total	0	0
Other assets:
Goodwill	0	0
Deferred charges	27,171	32,379
Other	8,031	9,601
Total assets	7,737,266	7,273,150
Current liabilities:
Current maturities of long-term debt	61,177	44,874
Accounts payable and accrued liabilities	22,084	20,245
Federal and state taxes	8,697	1,446
Total current liabilities	91,958	66,565
Intercompany payable	259,415	0
Intercompany note payable	0	0
Other noncurrent liabilities	4,236	1,322
Long-term debt	2,984,200	3,187,103
Deferred income taxes	264,358	282,214
Redeemable noncontrolling interests	0	0
Equity:
UHS common stockholders’ equity	4,133,099	3,735,946
Noncontrolling interest	0	0
Total equity	4,133,099	3,735,946
Liabilities and Equity, Total	7,737,266	7,273,150
Guarantors
Current assets:
Cash and cash equivalents	27,934	21,784	29,203	7,990
Accounts receivable, net	940,262	933,971
Supplies	69,744	67,847
Deferred income taxes	2,147	743
Other current assets	69,304	62,431
Total current assets	1,109,391	1,086,776
Investments in subsidiaries	1,821,777	1,661,296
Intercompany receivable	0	0
Intercompany note receivable	0	0
Property and equipment	4,664,695	4,494,567
Less: accumulated depreciation	(1,828,173)	(1,686,192)
Property, plant and equipment, net, Total	2,836,522	2,808,375
Other assets:
Goodwill	2,862,325	2,764,555
Deferred charges	5,641	5,402
Other	259,784	283,302
Total assets	8,895,440	8,609,706
Current liabilities:
Current maturities of long-term debt	1,214	1,260
Accounts payable and accrued liabilities	1,018,055	1,051,309
Federal and state taxes	0	0
Total current liabilities	1,019,269	1,052,569
Intercompany payable	248,325	512,490
Intercompany note payable	1,267,637	1,222,637
Other noncurrent liabilities	217,605	189,456
Long-term debt	17,095	20,212
Deferred income taxes	0	0
Redeemable noncontrolling interests	0	0
Equity:
UHS common stockholders’ equity	6,125,509	5,612,342
Noncontrolling interest	0	0
Total equity	6,125,509	5,612,342
Liabilities and Equity, Total	8,895,440	8,609,706
Non Guarantors
Current assets:
Cash and cash equivalents	11,589	10,285	10,508	9,248
Accounts receivable, net	388,038	348,764
Supplies	42,974	40,268
Deferred income taxes	0	0
Other current assets	12,155	15,223
Total current assets	454,756	414,540
Investments in subsidiaries	0	0
Intercompany receivable	507,740	408,682
Intercompany note receivable	1,267,637	1,222,637
Property and equipment	1,851,219	1,717,463
Less: accumulated depreciation	(911,649)	(846,149)
Property, plant and equipment, net, Total	939,570	871,314
Other assets:
Goodwill	526,053	526,658
Deferred charges	2,301	2,538
Other	42,926	55,181
Total assets	3,740,983	3,501,550
Current liabilities:
Current maturities of long-term debt	22,492	22,185
Accounts payable and accrued liabilities	62,477	41,508
Federal and state taxes	0	0
Total current liabilities	84,969	63,693
Intercompany payable	0	0
Intercompany note payable	0	0
Other noncurrent liabilities	70,600	77,777
Long-term debt	8,659	2,900
Deferred income taxes	0	0
Redeemable noncontrolling interests	250,213	239,552
Equity:
UHS common stockholders’ equity	3,265,925	3,062,494
Noncontrolling interest	60,617	55,134
Total equity	3,326,542	3,117,628
Liabilities and Equity, Total	3,740,983	3,501,550
Consolidating Adjustments
Current assets:
Cash and cash equivalents	0	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	(9,391,434)	(8,674,836)
Intercompany receivable	(507,740)	(512,490)
Intercompany note receivable	(1,267,637)	(1,222,637)
Property and equipment	0	0
Less: accumulated depreciation	0	0
Property, plant and equipment, net, Total	0	0
Other assets:
Goodwill	0	0
Deferred charges	0	0
Other	0	0
Total assets	(11,166,811)	(10,409,963)
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	(507,740)	(512,490)
Intercompany note payable	(1,267,637)	(1,222,637)
Other noncurrent liabilities	0	0
Long-term debt	0	0
Deferred income taxes	0	0
Redeemable noncontrolling interests	0	0
Equity:
UHS common stockholders’ equity	(9,391,434)	(8,674,836)
Noncontrolling interest	0	0
Total equity	(9,391,434)	(8,674,836)
Liabilities and Equity, Total	$ (11,166,811)	$ (10,409,963)