Derivative Financial Instruments (Schedule Of Cash Flow Hedging Instruments) (Detail) - Cash Flow Hedging - Designated as Hedging Instrument $ in Thousands	Jun. 30, 2017 USD ($)
Interest Rate Swap, $200 million, June 2019
Derivative [Line Items]
Notional amount	$ 200,000
Fair Value Asset (Liability)	96
Interest Rate Swap, $250 million, July 2019
Derivative [Line Items]
Notional amount	250,000
Fair Value Asset (Liability)	3,750
Interest Rate Swap, $275 million, August 2019
Derivative [Line Items]
Notional amount	275,000
Fair Value Asset (Liability)	4,671
Interest Rate Swap, $200 million, June 2020
Derivative [Line Items]
Notional amount	200,000
Fair Value Asset (Liability)	122
Total Interest Rate Swap
Derivative [Line Items]
Notional amount	925,000
Fair Value Asset (Liability)	8,639
Interest Rate Cap, $50 million, September 2017
Derivative [Line Items]
Notional amount	50,000
Fair Value Asset (Liability)	0
Interest Rate Cap, $40 million, September 2017
Derivative [Line Items]
Notional amount	40,000
Fair Value Asset (Liability)	5
Total Interest Rate Cap
Derivative [Line Items]
Notional amount	90,000
Fair Value Asset (Liability)	5
Interest Rate Swaps and Caps
Derivative [Line Items]
Notional amount	1,015,000
Fair Value Asset (Liability)	$ 8,644