The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

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Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

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Amount of loss contingency liability.

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Amount of damages awarded to the plaintiff in the legal matter.

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-Topic 450

-SubTopic 20

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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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The estimated maximum amount of possible loss from the contingency.

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Legal Proceedings - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended
	Sep. 30, 2014	Dec. 31, 2010	Dec. 31, 2014	Oct. 17, 2014
Loss Contingencies [Line Items]
Loss contingency accrual			$ 35,000,000
Estimate of possible losses			57,000,000
Other Litigation Cases
Loss Contingencies [Line Items]
Maximum exposure of litigation			150,000
Keystone
Loss Contingencies [Line Items]
Gain on litigation	69,000,000
Escrow reserve				25,000,000
Keystone \| Breach of Contract
Loss Contingencies [Line Items]
Damages awarded		34,300,000
Keystone \| Slander
Loss Contingencies [Line Items]
Damages awarded		39,000,000
Keystone \| Exemplary Damages Award
Loss Contingencies [Line Items]
Damages awarded		$ 7,500,000