Preferred Stock - Additional Information (Detail) (USD $)			0 Months Ended				0 Months Ended
	Jun. 30, 2014	Apr. 29, 2014	Apr. 29, 2014 Non-Voting Series A Preferred Stock [Member]	Apr. 30, 2014 Non-Voting Series A Preferred Stock [Member]	Jun. 30, 2014 Preferred Stock [Member]	Jul. 29, 2014 Subsequent Event [Member]	Jul. 29, 2014 Subsequent Event [Member] Non-Voting Series A Preferred Stock [Member]	Jul. 29, 2014 Subsequent Event [Member] Non-Voting Series A Preferred Stock [Member]	Apr. 29, 2014 Maximum [Member]
Class of Stock [Line Items]
Issuance of non-voting Series A Preferred Stock, shares issued				9,000
Additional shares issued								1,800
Non-voting Series A Preferred Stock, shares purchased price				$ 90,000,000				$ 18,000,000
Non-voting Series A Preferred Stock, maximum number of shares issued		1,800				1,800			18,000
Amount Of Non Voting Series A Preferred Stock Purchase price			18,000,000				18,000,000
Non-voting Series A Preferred Stock, maximum aggregate consideration		180,000,000
Non-voting Series A Preferred Stock, cumulative, non-participating cash dividend			0.10%
Redemption of Preferred Stock at original purchase price	$ 10,000
Estimated fair value of derivatives					$ 3,000,000