Debt and Borrowings (Narrative) (Details) € in Thousands, £ in Thousands, $ in Thousands	3 Months Ended
	Sep. 30, 2015 GBP (£)	Sep. 30, 2015 USD ($)	Sep. 30, 2015 EUR (€)	Jun. 30, 2015 USD ($)
Line of Credit Facility [Line Items]
Aggregate principal amount of senior notes		$ 150,000
Senior notes term, in years	10
Senior notes maturity date	May 02, 2016
Senior notes interest percentage	5.98%	5.98%	5.98%
Senior notes outstanding		$ 150,000		$ 150,000
Line Of Credit Potential Incremental Borrowing Capacity Post-Amendment		350,000
Revolving credit facility expiration date	Dec. 12, 2019
Interest coverage ratio	4.0
Leverage ratio	3.5
Consolidated leverage ratio	4.0
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Revolving credit facility		1,000,000
Borrowings outstanding under credit agreement		$ 680,390		660,216
Long-term Debt, Weighted Average Interest Rate	1.56%	1.56%	1.56%
Revolving Credit Facility [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.20%
Revolving Credit Facility [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.30%
Eurocurrency Rate [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.875%
Eurocurrency Rate [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.70%
Base Rate [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.00%
Base Rate [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.70%
Tilda borrowing arrangement [Member]
Line of Credit Facility [Line Items]
Revolving credit facility | £	£ 50,393
Borrowings outstanding under credit agreement		$ 33,483		$ 29,600
Short-term Debt, Weighted Average Interest Rate	2.80%	2.80%	2.80%
Mona [Member]
Line of Credit Facility [Line Items]
Revolving credit facility | €			€ 12,000
Short-term Debt, Weighted Average Interest Rate	2.50%	2.50%	2.50%