Income Tax (Narrative) (Details) (USD $)	6 Months Ended		12 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011 Australia [Member]	Jun. 30, 2011 Australia [Member]
Investments, Owned, Federal Income Tax Note [Line Items]
Credit facility				$ 100,000,000
Change in valuation allowance on net deferred tax assets	(373,000)	14,422,000	13,800,000
Accrued income taxes	25,100,000
Accrued income taxes, current	14,600,000
Non-current tax liabilities	10,500,000
Accrued income taxes, current judgment	3,500,000
Impact of effective tax rate if recognized	1,000,000
Uncertain tax position probable changes in next 12 months, minimum	900,000
Uncertain tax position probable changes in next 12 months, maximum	1,800,000
Net tax balance	$ 2,100,000