Assets, Liabilities and Temporary Equity Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Assets
Available-for-sale securities	$ 109,568	$ 107,050
Liabilities
Contingent earn-out obligations	8,565	$ 9,977
Fair Value, Measurements, Recurring
Assets
Available-for-sale securities	48,124
Cash surrender value of life insurance policies	61,444
Funds on deposit with third parties	79,459
Liabilities
Contingent earn-out obligations	8,565
Temporary equity
Noncontrolling interests subject to put provisions	979,848
Fair Value, Measurements, Recurring \| Interest rate cap agreements
Assets
Interest rate cap agreements	4,712
Fair Value, Measurements, Recurring \| Level 1
Assets
Available-for-sale securities	48,124
Cash surrender value of life insurance policies	0
Funds on deposit with third parties	79,459
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
Available-for-sale securities	0
Cash surrender value of life insurance policies	61,444
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	4,712
Fair Value, Measurements, Recurring \| Level 3
Assets
Available-for-sale securities	0
Cash surrender value of life insurance policies	0
Funds on deposit with third parties	0
Liabilities
Contingent earn-out obligations	8,565
Temporary equity
Noncontrolling interests subject to put provisions	979,848
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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The aggregate fair value as of the reporting date of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

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