Asset Purchase Agreement, Sale of Securities, Amount

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- Definition

Business Acquisition, Equity Interest Issued or Issuable, Price Per Share

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- Definition

Business Combination, Aggregate Purchase Price, Number of Business Days Prior to Proxy Statement

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- Definition

Business Combination, Aggregate Purchase Price, Percentage of Acquiree Value

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- Definition

Conversion of Preferred Stock, Shares Issued Upon Conversion

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- Definition

Debt Instrument, Maximum Borrowing Commitment

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- Definition

Equity Method Investment, Sale of Ownership Percentage

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No definition available.

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- Definition

Letter Agreement, Aggregate Amount Payable to Manager

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- Definition

Letter Agreement, Aggregate Amount Payable to Manager, Monthly Installments

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- Definition

Loss Contingency, Number of Lawsuits

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- Definition

Mortgage Loans on Real Estate, Commitment to Lend, Unfunded Amount

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- Definition

Stock Purchase Agreement, Sale of Stock Commitment, Value

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No definition available.

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- Definition

Stock Purchase Agreement, Threshold Share Price

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No definition available.

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
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- Definition

Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

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No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.28)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29
-Article 5

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- Definition

Aggregate par or stated value of issued nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable preferred shares, par value and other disclosure concepts are in another section within stockholders' equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29
-Article 5

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- Definition

The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

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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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Commitments and Contingencies - Additional Information (Detail) $ / shares in Units, € in Thousands		1 Months Ended
	Feb. 26, 2016 USD ($) business_day $ / shares shares	Feb. 28, 2015 USD ($)	Feb. 28, 2015 EUR (€)	Mar. 31, 2016 USD ($) lawsuit $ / shares	Dec. 31, 2015 $ / shares	Feb. 28, 2015 EUR (€)	Sep. 30, 2014 USD ($)	Sep. 30, 2014 EUR (€)	Sep. 30, 2013 USD ($)	Sep. 30, 2013 EUR (€)
Schedule of Equity Method Investments [Line Items]
Preferred stock, par value (in dollars per share) \| $ / shares				$ 0.01	$ 0.01
Number lawsuits \| lawsuit				2
Commercial mortgage loans [Member]
Schedule of Equity Method Investments [Line Items]
Unfunded loan commitments				$ 108,883,000
Subordinate loans [Member]
Schedule of Equity Method Investments [Line Items]
Unfunded loan commitments				$ 99,850,000
KBCD Partnership [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest									21.00%	21.00%
BKB Bank [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest				11.00%
Commitment to Invest in KBCD [Member]
Schedule of Equity Method Investments [Line Items]
Commitment to invest/purchase							$ 50,000,000	€ 38,000	$ 50,000,000	€ 38,000
Unfunded Commitment, Champ L.P. [Member]
Schedule of Equity Method Investments [Line Items]
Commitment to invest/purchase		$ 3,675,000				€ 3,229
Champ LP [Member]
Schedule of Equity Method Investments [Line Items]
Sale of equity method investment, percentage		48.00%	48.00%
Proceeds from sale of equity method investments		$ 20,794,000	€ 16,314
Apollo Residential Mortgage, Inc. Merger [Member]
Schedule of Equity Method Investments [Line Items]
Aggregate purchase price, percentage of acquiree value	89.25%
Purchase price value, number of business days prior to Proxy Statement \| business_day	3
Shares issuable under agreement, price per share (in dollars per share) \| $ / shares	$ 16.75
Number of shares issued upon conversion \| shares	1
Preferred stock, par value (in dollars per share) \| $ / shares	$ 0.01
Letter Agreement, aggregate amount payable to manager, monthly installment amount	$ 150,000
Series C Cumulative Redeemable Perpetual Preferred Stock [Member] \| Apollo Residential Mortgage, Inc. Merger [Member]
Schedule of Equity Method Investments [Line Items]
Dividend rate, preferred stock	8.00%
Apollo Residential Mortgage, Inc. [Member] \| Series A Cumulative Redeemable Perpetual Preferred Stock [Member] \| Apollo Residential Mortgage, Inc. Merger [Member]
Schedule of Equity Method Investments [Line Items]
Preferred stock, value	$ 172,500,000
Dividend rate, preferred stock	8.00%
Champ LP [Member] \| KBC Bank Deutschland AG [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest							35.00%	35.00%
Wholly-owned Subsidiary [Member] \| Champ Limited Partnership [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest							59.00%	59.00%
Maximum [Member] \| Apollo Residential Mortgage, Inc. Merger [Member]
Schedule of Equity Method Investments [Line Items]
Number of shares issuable under agreement \| shares	13,400,000
Letter Agreement, aggregate amount payable to manager	$ 500,000
Bridge Loan [Member] \| Athene Holding Ltd. [Member] \| Apollo Residential Mortgage, Inc. Merger [Member]
Schedule of Equity Method Investments [Line Items]
Borrowing commitment	200,000,000
Residential Mortgage Backed Securities [Member] \| Athene Holding Ltd. [Member] \| Maximum [Member] \| Apollo Residential Mortgage, Inc. Merger [Member]
Schedule of Equity Method Investments [Line Items]
Asset Purchase Agreement, sale of securities, amount	$ 1,200,000,000
Common Stock [Member] \| Apollo Residential Mortgage, Inc. Merger [Member]
Schedule of Equity Method Investments [Line Items]
Stock Purchase Agreement, threshold share price (in dollars per share) \| $ / shares	$ 16.75
Common Stock [Member] \| Athene Holding Ltd. [Member] \| Maximum [Member] \| Apollo Residential Mortgage, Inc. Merger [Member]
Schedule of Equity Method Investments [Line Items]
Stock Purchase Agreement, sale of stock commitment, value	$ 20,000,000