Charge related to recognition of premium deficiency non-insurance warranty contract.

No definition available.

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- Definition

Duration of drilling contract.

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No definition available.

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- Definition

Non-insurance warranty product term.

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- Definition

For an unclassified balance sheet, the amount due from customers or clients for goods or services that have been delivered or sold in the normal course of business, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

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Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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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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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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Revenue from Contracts with Customers - Additional Information (Detail) - USD ($)	3 Months Ended	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2018	Jan. 01, 2018
Disaggregation of Revenue [Line Items]
Receivables from contracts with customers, included within Receivables	$ 422,000,000	$ 422,000,000	$ 488,000,000
Deferred revenue, included within Other liabilities	3,200,000,000	3,200,000,000	$ 3,000,000,000
Revenue recognized		473,000,000
Contract cost	2,400,000,000	2,400,000,000
Amortization expense, contract cost	179,000,000	350,000,000
Premium deficiency charges, non-insurance warranty contract		0
Performance obligations, total	12,300,000,000	12,300,000,000
2018 [Member]
Disaggregation of Revenue [Line Items]
Performance obligations, total	1,100,000,000	1,100,000,000
2019 [Member]
Disaggregation of Revenue [Line Items]
Performance obligations, total	$ 1,900,000,000	$ 1,900,000,000
Minimum [Member] \| CNA Financial [Member]
Disaggregation of Revenue [Line Items]
Non-insurance warranty product term		1 month
Minimum [Member] \| Diamond Offshore [Member]
Disaggregation of Revenue [Line Items]
Contract term		2 months
Minimum [Member] \| Boardwalk Pipeline [Member]
Disaggregation of Revenue [Line Items]
Contract term		1 year
Maximum [Member] \| CNA Financial [Member]
Disaggregation of Revenue [Line Items]
Non-insurance warranty product term		10 years
Maximum [Member] \| Diamond Offshore [Member]
Disaggregation of Revenue [Line Items]
Contract term		60 months
Maximum [Member] \| Boardwalk Pipeline [Member]
Disaggregation of Revenue [Line Items]
Contract term		20 years