Supplemental Cash Flow Disclosure (Tables)

12 Months Ended

Dec. 31, 2012

Supplemental Cash Flow Elements [Abstract]

Schedule of Depreciation and Amortization Expense

Depreciation and amortization expense is comprised of the following (in thousands):

	Year Ended December 31,
	2012		2011		2010
Depreciation and amortization from continuing operations	$	123,879	$	118,232	$	116,439
Depreciation and amortization from discontinued operations	5,607		20,660		31,224
Total depreciation and amortization expense	$	129,486	$	138,892	$	147,663