Condensed Consolidating Financial Statements Schedule of Error Corrections and Prior Period Adjustments (Details) (USD $)	9 Months Ended						3 Months Ended		6 Months Ended	9 Months Ended	12 Months Ended			9 Months Ended		3 Months Ended		6 Months Ended	9 Months Ended	12 Months Ended			9 Months Ended		3 Months Ended		6 Months Ended	9 Months Ended	12 Months Ended			9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013 Guarantor Subsidiaries [Member]	Sep. 30, 2012 Guarantor Subsidiaries [Member]	Sep. 30, 2013 Non-Guarantor Subsidiaries [Member]	Sep. 30, 2012 Non-Guarantor Subsidiaries [Member]	Mar. 31, 2013 As Previously Reported [Member]	Mar. 31, 2012 As Previously Reported [Member]	Jun. 30, 2012 As Previously Reported [Member]	Sep. 30, 2012 As Previously Reported [Member]	Dec. 31, 2012 As Previously Reported [Member]	Dec. 31, 2011 As Previously Reported [Member]	Dec. 31, 2010 As Previously Reported [Member]	Sep. 30, 2012 As Previously Reported [Member] Guarantor Subsidiaries [Member]	Sep. 30, 2012 As Previously Reported [Member] Non-Guarantor Subsidiaries [Member]	Mar. 31, 2013 Adjustment [Member]	Mar. 31, 2012 Adjustment [Member]	Jun. 30, 2012 Adjustment [Member]	Sep. 30, 2012 Adjustment [Member]	Dec. 31, 2012 Adjustment [Member]	Dec. 31, 2011 Adjustment [Member]	Dec. 31, 2010 Adjustment [Member]	Sep. 30, 2012 Adjustment [Member] Guarantor Subsidiaries [Member]	Sep. 30, 2012 Adjustment [Member] Non-Guarantor Subsidiaries [Member]	Mar. 31, 2013 As Revised [Member]	Mar. 31, 2012 As Revised [Member]	Jun. 30, 2012 As Revised [Member]	Sep. 30, 2012 As Revised [Member]	Dec. 31, 2012 As Revised [Member]	Dec. 31, 2011 As Revised [Member]	Dec. 31, 2010 As Revised [Member]	Sep. 30, 2012 As Revised [Member] Guarantor Subsidiaries [Member]	Sep. 30, 2012 As Revised [Member] Non-Guarantor Subsidiaries [Member]
Net cash provided (used) by operating activities	$ 105,009,000	$ 118,423,000	$ 18,718,000	$ 4,941,000	$ 26,221,000	$ 26,410,000	$ 1,874,000	$ 4,412,000	$ 37,802,000	$ 121,276,000	$ 161,020,000	$ 134,844,000	$ 144,935,000	$ (1,928,000)	$ 36,131,000	$ (1,729,000)	$ (475,000)	$ (1,537,000)	$ (2,853,000)	$ (10,898,000)	$ (3,475,000)	$ (1,120,000)	$ 6,869,000	$ (9,721,000)	$ 145,000	$ 3,937,000	$ 36,265,000	$ 118,423,000	$ 150,122,000	$ 131,369,000	$ 143,815,000	$ 4,941,000	$ 26,410,000
Issuance of mezzanine and other notes receivable	0	(4,236,000)	0	0	0	0	(1,729,000)	(3,719,000)	(5,820,000)	(7,305,000)	(34,925,000)	(12,766,000)	(11,786,000)	(3,068,000)	0	1,729,000	583,000	1,684,000	3,069,000	11,189,000	3,539,000	1,203,000	3,068,000	0	0	(3,136,000)	(4,136,000)	(4,236,000)	(23,736,000)	(9,227,000)	(10,583,000)	0	0
Collections of mezzanine and other notes receivable	224,000	110,000	0	0	0	0	19,000	151,000	210,000	326,000	3,561,000	4,754,000	5,083,000	216,000	0	0	(108,000)	(147,000)	(216,000)	(291,000)	(64,000)	(83,000)	(216,000)	0	19,000	43,000	63,000	110,000	3,270,000	4,690,000	5,000,000	0	0
Advances to and investments in affiliates			(1,280,000)	(9,721,000)	0	0								0	0								(9,721,000)	0								(9,721,000)	0
Net cash provided (used) in investing activities	(28,350,000)	(16,709,000)	(22,736,000)	(5,220,000)	(2,457,000)	(9,636,000)	13,816,000	1,496,000	10,387,000	19,562,000	57,999,000	23,804,000	32,155,000	1,649,000	(9,636,000)	(1,729,000)	(475,000)	(1,537,000)	(2,853,000)	(10,898,000)	(3,475,000)	(1,120,000)	(6,869,000)	0	12,087,000	1,021,000	8,850,000	16,709,000	47,101,000	20,329,000	31,035,000	(5,220,000)	(9,636,000)
Proceeds from contributions from affiliates			0	0	2,280,000	9,721,000								0	0								0	9,721,000								0	9,721,000
Net cash provided (used) by financing activities	$ (48,115,000)	$ (94,520,000)	$ 4,048,000	$ 122,000	$ 2,249,000	$ 9,707,000								$ 122,000	$ (14,000)								$ 0	$ 9,721,000								$ 122,000	$ 9,707,000