Severance Costs (Schedule Of Aggregate Net Severance Charges) (Detail) (Executive Officers [Member], USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011
Executive Officers [Member]
Restructuring Cost and Reserve [Line Items]
Accrued severance charges, beginning of period	$ 3,518	$ 5,441
Payments for period	(2,157)	(1,802)
Interest accretion	163	236
Accrued severance charges, end of period	$ 1,524	$ 3,875

Liability for amount due employees, in addition to wages and any other money that employers owe employees, when their employment ends through a layoff or other termination. For example, a company may provide involuntarily terminated employees with a lump sum payment equal to one week's salary for every year of employment.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Other Postemployment Benefits

-URI http://asc.fasb.org/extlink&oid=6519534

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 112

-Paragraph 1

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Name:	us-gaap_SupplementalUnemploymentBenefitsSeveranceBenefits
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant