Segment Information (Details 2) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Financial information with respect to entity's operations by geographic area
Operating revenues and Earnings (losses) from unconsolidated affiliates:	$ 1,783,407,000	$ 1,810,911,000	$ 1,616,405,000	$ 1,587,173,000	$ 1,605,390,000	$ 1,548,965,000	$ 1,459,326,000	$ 1,538,373,000	$ 6,797,896,000	$ 6,152,054,000	$ 6,554,333,000
Property, plant and equipment, net	8,599,125,000				8,597,813,000				8,599,125,000	8,597,813,000	8,712,088,000
Goodwill	173,928,000				512,964,000				173,928,000	512,964,000	472,326,000
U.S.
Financial information with respect to entity's operations by geographic area
Operating revenues and Earnings (losses) from unconsolidated affiliates:									4,695,977,000	4,146,125,000	4,625,614,000
Property, plant and equipment, net	5,205,296,000				5,474,746,000				5,205,296,000	5,474,746,000	5,179,578,000
Goodwill	146,310,000				498,149,000				146,310,000	498,149,000	456,463,000
Outside the U.S.
Financial information with respect to entity's operations by geographic area
Operating revenues and Earnings (losses) from unconsolidated affiliates:									2,101,919,000	2,005,929,000	1,928,719,000
Property, plant and equipment, net	3,393,829,000				3,123,067,000				3,393,829,000	3,123,067,000	3,532,510,000
Goodwill	$ 27,618,000				$ 14,815,000				$ 27,618,000	$ 14,815,000	$ 15,863,000