STOCKHOLDERS' EQUITY - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Dec. 31, 2016	Jun. 30, 2015	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2018	Aug. 03, 2017	May 10, 2017	Feb. 07, 2017
Class Of Stock [Line Items]
Common stock, shares authorized	2,000,000,000		2,000,000,000
Common stock, par value	$ 0.1		$ 0.1
Common stock, shares issued	218,700,394		220,220,026
Common stock, shares outstanding	217,446,205		216,175,003
Granted shares of restricted stock			1,091,692
Corporation has authorized shares of preferred stock	50,000,000		50,000,000
Preferred stock, par value			$ 1
Stock repurchase plan treasury stock	1,254,189		4,045,023
Legal surplus reserve rate			10.00%
Original amount contributed in percentage			20.00%
Repurchased of common stock			386,611	255,102
Liquidation value per share			$ 25
Legal surplus reserve amount	$ 52,436		$ 52,436
Secondary Offering Of Common Stock						20,000,000
Conversion Of Stock Shares Issued1		852,831
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number	4,178,791		1,815,904
Trust Preferred Securities Exchanged Liquidation Value		$ 5,300
Legal Surplus Amount Additions	$ 9,600
Purchase Of Common Stock Secondary Offering								3,000,000
Omnibus Plan [Member]
Class Of Stock [Line Items]
Restricted stock available for issuance			7,713,767
Restricted Stock [Member]
Class Of Stock [Line Items]
Repurchased of common stock			243,102	65,498
First Fifty Percentage Restricted Stock Nonvest Awards [Member]
Class Of Stock [Line Items]
Percentage of restricted stock lapse					50.00%
Other Fifty Percentage Restricted Stock Nonvest Awards [Member]
Class Of Stock [Line Items]
Percentage of restricted stock lapse					50.00%
Thomas H Lee Partners [Member]
Class Of Stock [Line Items]
Percentage Of Stock Ownership			5.00%
Secondary Offering Of Common Stock						10,000,000		10,000,000
Oaktree Capital Management [Member]
Class Of Stock [Line Items]
Percentage Of Stock Ownership			5.00%
Secondary Offering Of Common Stock						10,000,000		10,000,000
Department Of Treasury [Member]
Class Of Stock [Line Items]
Secondary Offering Of Common Stock							10,291,553
Series A Preferred Stock [Member]
Class Of Stock [Line Items]
Preferred stock dividend rate percentage			7.125%
Series B Preferred Stock [Member]
Class Of Stock [Line Items]
Preferred stock dividend rate percentage			8.35%
Series C Preferred Stock [Member]
Class Of Stock [Line Items]
Preferred stock dividend rate percentage			7.40%
Series D Preferred Stock [Member]
Class Of Stock [Line Items]
Preferred stock dividend rate percentage			7.25%
Series E Preferred Stock [Member]
Class Of Stock [Line Items]
Preferred stock dividend rate percentage			7.00%