Derivative Financial Instruments - Additional Information (Details)	1 Months Ended			12 Months Ended
	Mar. 31, 2015 USD ($)	Jan. 31, 2014 USD ($)	Mar. 31, 2008 USD ($) agreement	Apr. 30, 2016 USD ($)	Apr. 25, 2015 USD ($)	Apr. 26, 2014 USD ($)	Aug. 31, 2015 USD ($)	Mar. 25, 2015 USD ($)
Derivative [Line Items]
Settlement of swap				$ 0	$ 29,003,000	$ 0
Interest Rate Cap [Member]
Derivative [Line Items]
Notional amount of derivatives				$ 575,000,000
New Interest Rate Cap Agreement [Member]
Derivative [Line Items]
Notional amount of derivatives						$ 100,000,000	$ 100,000,000
Interest Rate Swap Agreement [Member]
Derivative [Line Items]
Notional amount of derivatives		$ 250,000,000
Number of interest rate swap agreements | agreement			2
Notional amount of derivative asset			$ 100,000,000
Increase to other comprehensive income			$ 1,000,000
Percentage of senior notes		5.17%
Senior notes amount due		$ 250,000,000
Settlement of swap	$ 29,003,000
Interest Rate Swap Agreement [Member] | Long-term Debt [Member]
Derivative [Line Items]
Period of long-term loan		10 years
Interest Rate Swap Agreement [Member] | Senior Notes 3.48% [Member]
Derivative [Line Items]
Percentage of senior notes								3.48%
Aggregate principal amount								$ 250,000,000