Noncontrolling Interests Subject to Put Provisions (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
NONCONTROLLING INTERESTS SUBJECT TO PUT PROVISIONS
Potential obligations under time based put provisions	$ 111,793	$ 101,115
Potential additional obligations under event based put provisions	14,690	27,984
Redemption value	17,303	11,221
Estimated fair values for accounting purposes	1,647	2,672
Difference between the redemption value and estimated fair value for accounting purposes of the related noncontrolling interests	15,656	8,549
Noncontrolling interests subject to put provisions stated at estimated fair values for accounting purposes	110,827	120,550
Difference between the redemption value and estimated fair value for accounting purposes of the related noncontrolling interests	15,656	8,549
Noncontrolling interests subject to put provisions stated at maximum redemption value	126,483	129,099
Total change in fair value of noncontrolling interests subject to put provisions stated at maximum redemption	(5,999)	7,397	$ (9,617)
Noncontrolling Interests Subject to Put Provisions
NONCONTROLLING INTERESTS SUBJECT TO PUT PROVISIONS
Change in estimated fair values for accounting purposes	(2,000)	(9,963)
Change in the difference between the redemption value and estimated fair value for accounting purposes of the related noncontrolling interests	7,999	2,566
Total change in fair value of noncontrolling interests subject to put provisions stated at maximum redemption	$ 5,999	$ (7,397)	$ 9,617
Measurement Input, Discount Rate \| Minimum
NONCONTROLLING INTERESTS SUBJECT TO PUT PROVISIONS
Weighted average cost of capital	0.1400
Measurement Input, Discount Rate \| Maximum
NONCONTROLLING INTERESTS SUBJECT TO PUT PROVISIONS
Weighted average cost of capital	0.1950

Amount of potential additional obligations under event based put provisions.

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Redeemable Noncontrolling Interest, Equity, Accelerated Portion, Redemption Value

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Redeemable Noncontrolling Interest, Equity, Fair Value, Accelerated Portion

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Redeemable Noncontrolling Interest, Equity, Fair Value, Measurement Input

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Temporary Equity, Accretion to Redemption Value, Contractual

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Change in noncontrolling interest during the period as a result of a change in the redemption value of redeemable noncontrolling interest.

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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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Value of accretion of temporary equity to its redemption value during the period.

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Carrying amount, attributable to parent and noncontrolling interests, of an entity's issued and outstanding stock which is not included within permanent equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. Includes stock with a put option held by an ESOP and stock redeemable by a holder only in the event of a change in control of the issuer.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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