Assets, Liabilities and Temporary Equity Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Assets
Investments in mutual funds and common stock	$ 115,893	$ 107,050
Liabilities
Contingent earn-out obligations	11,674	$ 9,977
Fair Value, Measurements, Recurring
Assets
Investments in mutual funds and common stock	53,209
Cash surrender value of life insurance policies	62,684
Funds on deposit with third parties	75,671
Liabilities
Contingent earn-out obligations	11,674
Temporary equity
Noncontrolling interests subject to put provisions	1,009,704
Fair Value, Measurements, Recurring \| Interest rate cap agreements
Assets
Interest rate cap agreements	1,743
Fair Value, Measurements, Recurring \| Level 1
Assets
Investments in mutual funds and common stock	53,209
Cash surrender value of life insurance policies	0
Funds on deposit with third parties	75,671
Liabilities
Contingent earn-out obligations	0
Temporary equity
Noncontrolling interests subject to put provisions	0
Fair Value, Measurements, Recurring \| Level 1 \| Interest rate cap agreements
Assets
Interest rate cap agreements	0
Fair Value, Measurements, Recurring \| Level 2
Assets
Investments in mutual funds and common stock	0
Cash surrender value of life insurance policies	62,684
Funds on deposit with third parties	0
Liabilities
Contingent earn-out obligations	0
Temporary equity
Noncontrolling interests subject to put provisions	0
Fair Value, Measurements, Recurring \| Level 2 \| Interest rate cap agreements
Assets
Interest rate cap agreements	1,743
Fair Value, Measurements, Recurring \| Level 3
Assets
Investments in mutual funds and common stock	0
Cash surrender value of life insurance policies	0
Funds on deposit with third parties	0
Liabilities
Contingent earn-out obligations	11,674
Temporary equity
Noncontrolling interests subject to put provisions	1,009,704
Fair Value, Measurements, Recurring \| Level 3 \| Interest rate cap agreements
Assets
Interest rate cap agreements	$ 0

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount of liability recognized arising from contingent consideration in a business combination.

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Fair value portion of the amount that could be realized under a life insurance contract or contracts owned by the entity, commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

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The carrying amount of the asset transferred to a third party to serve as a deposit, which typically serves as security against failure by the transferor to perform under terms of an agreement.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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