Redeemable Noncontrolling Interest (Schedule of Redeemable Noncontrolling Interest) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance	$ 569,981	$ 542,020
Net income attributable to noncontrolling interest, including the contractual accretion of the put options	22,332	28,713	$ 4,750
Distribution to noncontrolling interest		(752)
Acquisition of noncontrolling interest	(592,313)	0	0
Ending balance	$ 0	$ 569,981	$ 542,020

Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

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- Definition

Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount of Net Income (Loss) attributable to noncontrolling interest.

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As of the reporting date, the aggregate carrying amount 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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