Subsequent Event (Details) - USD ($) $ in Millions	Jul. 24, 2015	Jul. 04, 2015	Sep. 27, 2012	Jul. 31, 2012
Revolving Credit Facility
Subsequent event
Maximum borrowing capacity	$ 300.0	$ 130.0		$ 130.0
Term of debt instrument	5 years
Additional increase in borrowing capacity of the line of credit available at the entity's option				50.0
Revolving Credit Facility | Subsequent Event
Subsequent event
Maximum borrowing capacity	$ 300.0
Amount borrowed under the facility	$ 82.5
Term of debt instrument	5 years
Revolving Credit Facility | High end of range | Subsequent Event
Subsequent event
Additional increase in borrowing capacity of the line of credit available at the entity's option	$ 200.0
Term Loan Facility
Subsequent event
Maximum borrowing capacity		$ 100.0		$ 100.0
Amount borrowed under the facility			$ 100.0