Segment Information (Schedule of Drilling Service Segment Divisions) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Segment Reporting Information [Line Items]
Identifiable assets	$ 1,426,377	$ 1,324,257	$ 1,229,623
Revenues	239,034	229,670
Drilling Services Segment [Member]
Segment Reporting Information [Line Items]
Identifiable assets	780,786	870,291
Drilling Rigs	62
Drilling Services Segment [Member] | South Texas [Member]
Segment Reporting Information [Line Items]
Drilling Rigs	14
Drilling Services Segment [Member] | West Texas [Member]
Segment Reporting Information [Line Items]
Drilling Rigs	18
Drilling Services Segment [Member] | North Dakota [Member]
Segment Reporting Information [Line Items]
Drilling Rigs	11
Drilling Services Segment [Member] | UTAH
Segment Reporting Information [Line Items]
Drilling Rigs	7
Drilling Services Segment [Member] | Appalachia [Member]
Segment Reporting Information [Line Items]
Drilling Rigs	4
Drilling Services Segment [Member] | Colombia [Member]
Segment Reporting Information [Line Items]
Identifiable assets	153,158	151,498
Drilling Rigs	8
Revenues	$ 22,164	$ 30,775