CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (unaudited) - USD ($) $ in Thousands		Total	FCB Financial Holdings, Inc.	Impact from Adoption		Preferred Stock	Common Stock	Common Stock FCB Financial Holdings, Inc.	Additional Paid-in Capital	Additional Paid-in Capital FCB Financial Holdings, Inc.	Treasury Stock	Treasury Stock FCB Financial Holdings, Inc.	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Retained Earnings FCB Financial Holdings, Inc.	Retained Earnings Impact from Adoption
Accounting Standards Update [Extensible List]		us-gaap:AccountingStandardsUpdate201602Member
Balance at Dec. 31, 2018		$ 3,133,602		$ 4,270		$ 195,140	$ 143,300		$ 3,060,561		$ (1,014,746)		$ (94,420)	$ 843,767		$ 4,270
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		276,370												276,370
Other comprehensive income (loss), net of income taxes		143,709											143,709
Issuance of common stock, net of issuance costs			$ 704,146					$ 22,043		$ 682,103
Common stock issued			877,570									$ 1,014,746			$ (137,176)
Fair value of exchanged equity awards and warrants attributed to purchase price			$ 43,972							$ 43,972
Cash dividends declared on common stock		(94,471)												(94,471)
Cash dividends declared on preferred stock	[1]	(6,300)												(6,300)
Repurchases of stock including costs to repurchase		(345,170)									(345,170)
Restricted share unit vesting and taxes paid related to net share settlement		(8,643)					285		(8,928)
Stock options/warrants exercised, net		8,536					452		7,815		269
Share-based compensation expense		16,225							16,225
Balance at Jun. 30, 2019		4,753,816				195,140	166,080		3,801,748		(344,901)		49,289	886,460
Balance at Mar. 31, 2019		4,597,753				195,140	165,929		3,794,262		(319,898)		(18,342)	780,662
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		156,184												156,184
Other comprehensive income (loss), net of income taxes		67,631											67,631
Cash dividends declared on common stock		(47,236)												(47,236)
Cash dividends declared on preferred stock	[2]	(3,150)												(3,150)
Repurchases of stock including costs to repurchase		(25,003)									(25,003)
Restricted share unit vesting and taxes paid related to net share settlement		(231)					50		(281)
Stock options/warrants exercised, net		1,887					101		1,786
Share-based compensation expense		5,981							5,981
Balance at Jun. 30, 2019		$ 4,753,816				195,140	166,080		3,801,748		(344,901)		49,289	886,460
Accounting Standards Update [Extensible List]		us-gaap:AccountingStandardsUpdate201613Member
Balance at Dec. 31, 2019		$ 4,941,690		(35,721)	[3]	537,145	166,801		3,819,336		(715,560)		65,641	1,068,327		(35,721)	[3]
Accounting Standards Update [Extensible List]		us-gaap:AccountingStandardsUpdate201613Member
Balance at Dec. 31, 2019		$ 4,941,690		$ (35,721)	[3]	537,145	166,801		3,819,336		(715,560)		65,641	1,068,327		$ (35,721)	[3]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		131,712												131,712
Other comprehensive income (loss), net of income taxes		137,329											137,329
Cash dividends declared on common stock		(97,210)												(97,210)
Cash dividends declared on preferred stock	[1]	(16,581)												(16,581)
Repurchases of stock including costs to repurchase		(16,246)									(16,246)
Restricted share unit vesting and taxes paid related to net share settlement		(7,404)					379		(7,783)
Stock options/warrants exercised, net		6,479					226		6,253
Share-based compensation expense		8,920							8,920
Balance at Jun. 30, 2020		5,052,968				537,145	167,406		3,826,726		(731,806)		202,970	1,050,527
Balance at Mar. 31, 2020		5,065,205				537,145	167,360		3,821,357		(731,806)		256,911	1,014,238
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		93,192												93,192
Other comprehensive income (loss), net of income taxes		(53,941)											(53,941)
Cash dividends declared on common stock		(48,612)												(48,612)
Cash dividends declared on preferred stock	[2]	(8,291)												(8,291)
Restricted share unit vesting and taxes paid related to net share settlement		(147)					34		(181)
Stock options/warrants exercised, net		212					12		200
Share-based compensation expense		5,350							5,350
Balance at Jun. 30, 2020		$ 5,052,968				$ 537,145	$ 167,406		$ 3,826,726		$ (731,806)		$ 202,970	$ 1,050,527

[1] For the six months ended June 30, 2020, dividends per share were $0.78 and $0.74 for Series D and Series E Preferred Stock, respectively. For the six months ended June 30, 2019, dividends per share were $0.78 for Series D Preferred Stock.

[2] For the three months ended June 30, 2020, dividends per share were $0.39 and $0.37 for Series D and Series E Preferred Stock, respectively. For the three months ended June 30, 2019, dividends per share were $0.39 for Series D Preferred Stock.

[3] For additional information, see "Part I - Item 1. Financial Statements and Supplementary Data - Note 1 - Basis of Presentation" in this Report.