Condensed Consolidated Statements Of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
REVENUES:
Contract drilling	$ 272,688	$ 178,603	$ 770,942	$ 534,896
COSTS AND EXPENSES:
Contract drilling	117,963	87,374	337,352	245,060
Depreciation	30,352	15,650	86,412	46,419
General and administrative	13,663	11,856	44,152	37,502
Other, net	(55)	274	(68)	1,137
Total costs and expenses	161,923	115,154	467,848	330,118
OPERATING INCOME	110,765	63,449	303,094	204,778
OTHER INCOME (EXPENSE):
Interest expense, net of capitalized interest	(5,692)	(1,517)	(16,647)	(1,623)
Interest income	57	58	202	258
Other income (expense) total	(5,635)	(1,459)	(16,445)	(1,365)
INCOME BEFORE INCOME TAXES	105,130	61,990	286,649	203,413
PROVISION FOR INCOME TAXES	15,149	10,279	38,318	26,768
NET INCOME	$ 89,981	$ 51,711	$ 248,331	$ 176,645
EARNINGS PER COMMON SHARE (NOTE 2):
Basic (in dollars per share)	$ 1.38	$ 0.79	$ 3.79	$ 2.71
Diluted (in dollars per share)	$ 1.37	$ 0.79	$ 3.75	$ 2.69
WEIGHTED AVERAGE COMMON SHARES OUTSTANDING (NOTE 2):
Basic (in shares)	65,062	65,362	65,441	65,221
Diluted (in shares)	65,858	65,823	66,180	65,715