STOCKHOLDERS' EQUITY AND EARNINGS PER SHARE (Details) - USD ($)	3 Months Ended												12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Jan. 17, 2014	Jan. 16, 2014	Jul. 17, 2013	Jan. 23, 2013
Class of Stock
Purchase of treasury stock pursuant to the Stock Repurchase Program (in shares)																8,026,807
Weighted average price of shares repurchased (in dollars per share)																$ 24.89
Total cost of the Stock Repurchase Program																$ 200,000,000
Warrant
Shares of East West's common stock into which the warrant may be converted (in shares)																	230,282
MetroCorp
Warrant
Number of warrants exercised (in shares)	0												0
Common Stock
Class of Stock
Amount of stock repurchase authorized by the Board of Directors																			$ 100,000,000	$ 200,000,000
Quarterly Dividends
Dividends paid (in dollars per share)	$ 0.20	$ 0.20	$ 0.20	$ 0.20	$ 0.20	$ 0.20	$ 0.20	$ 0.20	$ 0.18	$ 0.18	$ 0.18	$ 0.18
Total cash dividends paid													$ 116,600,000	$ 116,200,000	$ 104,000,000
MetroCorp | MetroCorp
Warrant
Shares of East West's common stock into which the warrant may be converted (in shares)																		771,429