Derivative Financial Instruments Derivative Financial Instruments (Interest Rate Cap Derivative Summary) (Detail) - Jun. 30, 2015 - USD ($) $ in Thousands	Total
Interest Rate Cap Two Hundred Fifteen Million Notional May Two Thousand Sixteen Maturity \| Not Designated as Hedging Instrument
Interest Rate Cap Derivative Summary [Line Items]
Derivative, maturity date	May 03, 2016
Notional amount	$ 215,000
Fair Value as of End of Period	$ 2
Interest Rate Cap Fifty Six Million Five Hundred Thousand Notional August Two Thousand Sixteen Maturity \| Not Designated as Hedging Instrument
Interest Rate Cap Derivative Summary [Line Items]
Derivative, maturity date	Aug. 22, 2016
Notional amount	$ 56,500
Fair Value as of End of Period	$ 14
Interest Rate Cap One Hundred Million Notional March Two Thousand Seventeen Maturity \| Not Designated as Hedging Instrument
Interest Rate Cap Derivative Summary [Line Items]
Derivative, maturity date	Mar. 21, 2017
Notional amount	$ 100,000
Fair Value as of End of Period	$ 199
Interest Rate Cap Seventy Five Million Notional November Two Thousand Sixteen Maturity \| Not Designated as Hedging Instrument
Interest Rate Cap Derivative Summary [Line Items]
Derivative, maturity date	Nov. 16, 2016
Notional amount	$ 75,000
Fair Value as of End of Period	53
Total Interest Rate Cap
Interest Rate Cap Derivative Summary [Line Items]
Notional amount	796,500
Fair Value as of End of Period	$ 782
Cash Flow Hedging \| Interest Rate Cap Two Hundred Sixteen Million Five Hundred Thousand Notional August Two Thousand Sixteen Maturity \| Designated as Hedging Instrument
Interest Rate Cap Derivative Summary [Line Items]
Derivative, maturity date	Aug. 29, 2016
Notional amount	$ 216,500
Fair Value as of End of Period	$ 34
Cash Flow Hedging \| Interest Rate Cap Forty Three Million Five Hundred Thousand Notional August Two Thousand Sixteen Maturity \| Designated as Hedging Instrument
Interest Rate Cap Derivative Summary [Line Items]
Derivative, maturity date	Aug. 22, 2016
Notional amount	$ 43,500
Fair Value as of End of Period	$ 11
Cash Flow Hedging \| Interest Rate Cap Fifty Million Notional September Two Thousand Seventeen Maturity \| Designated as Hedging Instrument
Interest Rate Cap Derivative Summary [Line Items]
Derivative, maturity date	Sep. 15, 2017
Notional amount	$ 50,000
Fair Value as of End of Period	$ 253
Cash Flow Hedging \| Interest Rate Cap Forty Million Notional September Two Thousand Seventeen Maturity \| Designated as Hedging Instrument
Interest Rate Cap Derivative Summary [Line Items]
Derivative, maturity date	Sep. 30, 2017
Notional amount	$ 40,000
Fair Value as of End of Period	216
Cash Flow Hedging \| Total Interest Rate Cap \| Designated as Hedging Instrument
Interest Rate Cap Derivative Summary [Line Items]
Notional amount	350,000
Fair Value as of End of Period	$ 514

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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- Definition

Date the derivative contract matures, in CCYY-MM-DD format.

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- Definition

Fair value as of the balance sheet date of interest rate derivative assets, net of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized on the balance sheet.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13433-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 15

-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13495-108611

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[Line Items] for Interest Rate Cap Derivative Summary [Table]

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