Condensed Consolidating Financial Information (Schedule Of Condensed Consolidating Statement Of Cash Flows) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Net cash provided by operating activities	$ 83,242	$ 52,277
Net cash used in investing activities	(226,921)	(98,942)
Net cash provided by financing activities	139,136	64,493
Net increase (decrease) in cash and cash equivalents	(4,543)	17,828
CASH AND CASH EQUIVALENTS, beginning of period	28,112	4,128
CASH AND CASH EQUIVALENTS, end of period	23,569	21,956
Parent Company [Member]
Net cash provided by operating activities	31,279	28,724
Net cash used in investing activities	(189,383)	(90,639)
Net cash provided by financing activities	139,137	64,493
Net increase (decrease) in cash and cash equivalents	(18,967)	2,578
CASH AND CASH EQUIVALENTS, beginning of period	19,134	1,418
CASH AND CASH EQUIVALENTS, end of period	167	3,996
Combined Guarantor Subsidiaries [Member]
Net cash provided by operating activities	53,607	23,553
Net cash used in investing activities	(178,270)	(77,001)
Net cash provided by financing activities	140,091	53,092
Net increase (decrease) in cash and cash equivalents	15,428	(356)
CASH AND CASH EQUIVALENTS, beginning of period	7,263	2,710
CASH AND CASH EQUIVALENTS, end of period	22,691	2,354
Combined Non-Guarantor Subsidiaries [Member]
Net cash provided by operating activities	(1,644)
Net cash used in investing activities	(13,474)	(6,469)
Net cash provided by financing activities	14,114	22,075
Net increase (decrease) in cash and cash equivalents	(1,004)	15,606
CASH AND CASH EQUIVALENTS, beginning of period	1,715
CASH AND CASH EQUIVALENTS, end of period	711	15,606
Eliminations [Member]
Net cash used in investing activities	154,206	75,167
Net cash provided by financing activities	$ (154,206)	$ (75,167)