Segment Information (Schedule of Segment Reporting Information) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Segment Reporting Information [Line Items]
Identifiable assets	$ 1,271,408	$ 888,436	$ 1,271,408	$ 888,436	$ 1,172,754
Drilling services, revenues	119,048	106,523	243,352	206,279
Production services, revenues	110,776	64,762	218,450	118,355
Total revenues	229,824	171,285	461,802	324,634
Drilling services, operating costs	78,631	73,190	159,708	140,699
Production services, operating costs	65,683	37,754	126,379	70,982
Operating costs	144,314	110,944	286,087	211,681
Segment margin	85,510	60,341	175,715	112,953
Depreciation and amortization	39,989	32,424	78,362	64,680
Capital expenditures	108,976	63,806	221,353	98,500
Drilling Services Division [Member]
Segment Reporting Information [Line Items]
Identifiable assets	803,264	609,886	803,264	609,886
Segment margin	40,417	33,333	83,644	65,580
Depreciation and amortization	26,307	24,702	51,796	49,188
Capital expenditures	80,608	46,306	161,192	65,417
Production Services Division [Member]
Segment Reporting Information [Line Items]
Identifiable assets	432,584	254,901	432,584	254,901
Segment margin	45,093	27,008	92,071	47,373
Depreciation and amortization	13,391	7,510	26,109	15,005
Capital expenditures	27,634	17,301	59,188	32,745
Corporate [Member]
Segment Reporting Information [Line Items]
Identifiable assets	35,560	23,649	35,560	23,649
Segment margin	0	0	0	0
Depreciation and amortization	291	212	457	487
Capital expenditures	$ 734	$ 199	$ 973	$ 338