Relationship with Universal Health Realty Income Trust and Related Party Transactions - Additional Information (Detail) (USD $)	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Relationship with Universal Health Realty Income Trust
Related Party Transaction [Line Items]
Trust outstanding shares held, percentage	6.20%
Advisory fee earned	$ 571,000	$ 515,000
Pre-tax share of income from the Trust	300,000	300,000
Carrying value of investment in Trust	8,800,000		9,300,000
Market value of investment in Trust	45,400,000		39,900,000
Rent expense under operating leases	4,100,000	4,100,000
Non-controlling ownership interests by subsidiaries	100.00%
Chief Executive Officer
Related Party Transaction [Line Items]
Estimated payments to acquire life insurance policies	25,000,000
Estimated death benefit proceeds	33,000,000
Chief Executive Officer \| Trust Owned by Chief Executive Officer
Related Party Transaction [Line Items]
Estimated payments to acquire life insurance policies	$ 8,000,000

Estimated Payments to Acquire Life Insurance Policies

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Estimated Proceeds from Life Insurance Policies

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the aggregate value of each identified investment accounted for under the equity method of accounting based on the quoted market price for those investments in common stock for which a quoted market price is available.

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Fees earned for providing investment advice and research to customers. Such services may include the investment management of mutual funds and separate accounts.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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Reflects the sum of all other revenue and income realized from sales and other transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period.

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