Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Segment information
Net revenues	$ 664,138us-gaap_Revenues	$ 641,080us-gaap_Revenues
Income (loss) from operations	23,478us-gaap_OperatingIncomeLoss	18,051us-gaap_OperatingIncomeLoss
Depreciation and amortization	42,922us-gaap_DepreciationAndAmortization	47,366us-gaap_DepreciationAndAmortization
Income from unconsolidated affiliates	3,982	2,483
Capital expenditures	48,789penn_CapitalExpenditures	37,041penn_CapitalExpenditures
Total assets	2,280,678us-gaap_Assets		2,211,279us-gaap_Assets
Investment in and advances to unconsolidated affiliates	175,574		179,551
Goodwill and other intangible assets, net	646,775		648,144
East/Midwest
Segment information
Net revenues	386,544	349,449
Income (loss) from operations	19,094	9,602
Depreciation and amortization	28,273	26,823
Capital expenditures	38,574	10,110
Total assets	1,034,441		990,031
Investment in and advances to unconsolidated affiliates	93		94
Goodwill and other intangible assets, net	264,162		264,147
West
Segment information
Net revenues	62,585	60,920
Income (loss) from operations	6,509	8,057
Depreciation and amortization	2,387	1,549
Capital expenditures	2,851	6,430
Total assets	313,306		289,026
Goodwill and other intangible assets, net	145,079		145,054
Southern Plains
Segment information
Net revenues	210,269	223,757
Income (loss) from operations	24,574	21,227
Depreciation and amortization	10,782	17,251
Income from unconsolidated affiliates	3,788	2,452
Capital expenditures	6,448	19,343
Total assets	576,528		592,405
Investment in and advances to unconsolidated affiliates	111,257		115,469
Goodwill and other intangible assets, net	233,456		234,865
Other
Segment information
Net revenues	4,740	6,954
Income (loss) from operations	(26,699)	(20,835)
Depreciation and amortization	1,480	1,743
Income from unconsolidated affiliates	194	31
Capital expenditures	916	1,158
Total assets	356,403		339,817
Investment in and advances to unconsolidated affiliates	64,224		63,988
Goodwill and other intangible assets, net	$ 4,078		$ 4,078

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