Represents the maximum maturity period of foreign currency forward contracts that the Company may enter into, to hedge recognized foreign currency assets and liabilities to reduce the risk.

No definition available.

Name:	byi_ForeignCurrencyForwardContractsMaturityPeriodMaximum
Namespace Prefix:	byi_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) In Millions, unless otherwise specified	9 Months Ended
	Mar. 31, 2013	Mar. 31, 2013 GBP USD ($)	Mar. 31, 2013 GBP GBP (£)	Mar. 31, 2013 Forwards EUR USD ($)	Mar. 31, 2013 Forwards EUR EUR (€)	Jun. 30, 2012 Forwards EUR USD ($)	Jun. 30, 2012 Forwards EUR EUR (€)
Financial instruments
Maximum maturity period for foreign currency forward contracts	12 months
Fair value of financial instruments
Total amount outstanding under foreign currency forward contracts		$ 2.3	£ 1.5	$ 38.8	€ 30.0	$ 38.0	€ 30.0