Quarterly Results Quarterly Results (Unaudited) - Additional Information (Detail) (Chief Executive Officer Retirement Bonus, USD $) In Millions, unless otherwise specified	3 Months Ended
Dec. 31, 2013
Chief Executive Officer Retirement Bonus
Effect of Fourth Quarter Events [Line Items]
Other Labor-related Expenses	$ 8

Amount of payroll tax expense, compensation, postemployment and benefit-related expenses not elsewhere specified in the taxonomy (such as health plan, profit sharing, incentives, tuition reimbursement, other fringe benefits and perquisites) incurred in the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.4)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration