Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 505
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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Discount on preferred shares, or any unamortized balance thereof, shown separately as a deduction from the applicable account(s) as circumstances require.

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The percentage rate used to calculate dividend payments on preferred stock.

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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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- Definition

Carrying amount, attributable to parent, 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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The number of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders. Securities issued include securities outstanding and securities held in treasury. 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. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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Value of new stock classified as temporary equity issued during the period.

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RELATED PARTY TRANSACTIONS (Details) - USD ($)		6 Months Ended
RELATED PARTY TRANSACTIONS (Details) - USD ($)	Mar. 01, 2016	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Related Party Transaction [Line Items]
Dividend rate	1.25%
Series C convertible preferred stock		$ 504,700,000		$ 492,100,000
Dividends		0	$ 0
Equity Method Investee
Related Party Transaction [Line Items]
Standby letters of credit, recorded liability		800,000
Series C Preferred Stock
Related Party Transaction [Line Items]
Shares issued (in shares)	435,000
Shares issued	$ 435,000,000.0
Dividends payable		78,000,000.0
Private Placement
Related Party Transaction [Line Items]
Preferred stock, discount on shares		$ 8,700,000