Supplemental Disclosure to Statements of Cash Flows (Tables)

3 Months Ended

Mar. 31, 2012

Supplemental Disclosure to Statements of Cash Flows [Abstract]

Supplemental Disclosure to Statements of Cash Flows

	2012		2011
Write-off of fully depreciated/amortized property and deferred costs	$	7,643	$	14,125
Write-off of depreciated property and deferred costs due to sale	$	3,331	$	—
Write-off of origination costs related to preferred unit redemption	$	2,771	$	—