Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Dec. 31, 2011	Dec. 31, 2010
Cash flows from operating activities:
Net income	$ 50,390	$ 33,721
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion and amortization	38,639	34,930
Gain on distribution to non-controlling interest	(3,284)	(2,709)
Non-cash stock-based compensation expense	4,066	3,207
Tax benefit of stock-based compensation exercises	(3,086)	(952)
Restructuring on royalty interests in mineral properties	1,328
Deferred tax benefit	(847)	(1,208)
Changes in assets and liabilities:
Royalty receivables	(15,693)	(12,505)
Prepaid expenses and other assets	1,385	1,631
Accounts payable	(194)	(301)
Income taxes payable	1,947	2,237
Other liabilities	785	3,303
Net cash provided by operating activities	75,436	61,354
Cash flows from investing activities:
Acquisition of royalty interests in mineral properties	(148,182)	(279,500)
Proceeds on sale of Inventory - restricted	4,842	4,260
Deferred acquisition costs		(2,057)
Other	(128)	(96)
Net cash (used in) investing activities	(143,468)	(277,393)
Cash flows from financing activities:
Borrowing from credit facility	100,000
Repayment of debt	(37,800)	(23,000)
Common stock dividends	(12,209)	(9,953)
Distribution to non-controlling interests	(6,315)	(5,123)
Proceeds from the issuance of common stock	2,917
Tax benefit of stock-based compensation exercises	3,086	952
Other		(274)
Net cash provided by (used in) financing activities	49,679	(37,398)
Net increase (decrease) in cash and equivalents	(18,353)	(253,437)
Cash and equivalents at beginning of period	114,155	324,846
Cash and equivalents at end of period	$ 95,802	$ 71,409