Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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No definition available.

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Subsequent Events (Details) - USD ($)	Mar. 15, 2020	Jan. 24, 2020	Dec. 31, 2019	Dec. 31, 2018	Aug. 31, 2012
Senior notes \| 2.400% Senior Notes due 2030 \| Subsequent Event
Subsequent Event [Line Items]
Aggregate principal amount		$ 750,000,000
Interest rate on debt		2.40%
Series C Preferred Stock
Subsequent Event [Line Items]
Preferred stock, shares outstanding (in shares)			5,000	5,000
Liquidation preference per share (USD per share)					$ 100,000
Series C Preferred Stock, Depository Share
Subsequent Event [Line Items]
Liquidation preference per share (USD per share)					$ 25
Forecast \| Series C Preferred Stock
Subsequent Event [Line Items]
Preferred stock, shares outstanding (in shares)	5,000
Liquidation preference per share (USD per share)	$ 100,000
Forecast \| Series C Preferred Stock, Depository Share
Subsequent Event [Line Items]
Liquidation preference per share (USD per share)	$ 25.00