Related Party Transactions - Narrative (Details) $ in Millions		3 Months Ended
Feb. 15, 2019	Mar. 31, 2019 USD ($)
Maximum
Related Party Transaction [Line Items]
Percentage of consolidated group's net income due to Apollo Management		1.00%
Fee due to Apollo Management		$ 5
Affiliated transactions
Related Party Transaction [Line Items]
Initial term	8 years
Automatic twelve month extension	12 months
Automatic twelve month extension, eight years	8 years
Automatic twelve month extension, nine years	9 years
Term extension period	30 days
Beneficial Owner \| Maximum
Related Party Transaction [Line Items]
Ownership percentage	0.90

Related party transactions, automatic twelve month extension

No definition available.

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- Definition

Related party transactions, automatic twelve month extension, one

+ References

No definition available.

+ Details

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- Definition

Related party transactions, automatic twelve month extension, two

+ References

No definition available.

+ Details

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- Definition

Related party transactions, initial term

+ References

No definition available.

+ Details

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- Definition

Related party transaction, ownership percentage

+ References

No definition available.

+ Details

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- Definition

Related party transactions, term extension period

+ References

No definition available.

+ Details

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- Definition

Amounts due to recorded owners or owners with a beneficial interest of more than 10 percent of the voting interests or officers of the company. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-04(12))
-URI http://asc.fasb.org/extlink&oid=6488278&loc=d3e603758-122996

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(17))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(k)(1))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(a)(5))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Identify the stated interest rate per the agreement, for example, leasing and debt arrangements between related parties.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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