Related Party Transactions (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Related Party Transaction [Line Items]
Payments of dividends	$ 0	$ 550,000
Apollo Management Holdings, L.P. \| Management
Related Party Transaction [Line Items]
Management fee expense	1,000	5,000
Koch \| Affiliated Entity \| Structuring Fees
Related Party Transaction [Line Items]
Amounts of transaction		45,000
Koch \| Affiliated Entity \| Mandatorily Redeemable Preferred Stock
Related Party Transaction [Line Items]
Financial instruments subject to mandatory redemption, increase during period	25,000
Payments of dividends		$ 21,000
Apollo Global Securities, LLC \| Affiliated Entity
Related Party Transaction [Line Items]
Payments of stock issuance costs	$ 2,000
Apollo Global Securities, LLC \| Affiliated Entity \| Over-Allotment Option
Related Party Transaction [Line Items]
Shares issued in public offering (in shares)	4,200,000

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- Definition

The cash outflow for reacquisition of callable preferred stock.

+ References

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-Publisher FASB
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-Topic 230
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Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

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The cash outflow for cost incurred directly with the issuance of an equity security.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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- Definition

A fee charged for services from professionals such as doctors, lawyers and accountants. The term is often expanded to include other professions, for example, pharmacists charging to maintain a medicinal profile of a client or customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of transactions with related party during the financial reporting period.

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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

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

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