Assets, Liabilities and Temporary Equity Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Assets
Available for sale securities	$ 107,050	$ 90,322
Liabilities
Contingent earn-out obligations	7,217	29,050
Fair Value, Measurements, Recurring
Assets
Available for sale securities	47,404	33,482
Cash surrender value of life insurance policies	59,646	56,840
Funds on deposit with third parties	75,877	82,679
Liabilities
Contingent earn-out obligations	9,977	34,135
Temporary equity
Noncontrolling interests subject to put provisions	973,258	864,066
Fair Value, Measurements, Recurring \| Interest rate cap agreements
Assets
Interest rate derivative agreements	9,929	15,127
Fair Value, Measurements, Recurring \| Interest rate swap agreements
Assets
Interest rate derivative agreements		516
Fair Value, Measurements, Recurring \| Level 1
Assets
Available for sale securities	47,404	33,482
Funds on deposit with third parties	75,877	82,679
Fair Value, Measurements, Recurring \| Level 2
Assets
Cash surrender value of life insurance policies	59,646	56,840
Fair Value, Measurements, Recurring \| Level 2 \| Interest rate cap agreements
Assets
Interest rate derivative agreements	9,929	15,127
Fair Value, Measurements, Recurring \| Level 2 \| Interest rate swap agreements
Assets
Interest rate derivative agreements		516
Fair Value, Measurements, Recurring \| Level 3
Liabilities
Contingent earn-out obligations	9,977	34,135
Temporary equity
Noncontrolling interests subject to put provisions	$ 973,258	$ 864,066

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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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