Bank segment (HEI only) Statements of Income Data (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	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, 2015	Dec. 31, 2014	Dec. 31, 2013
Interest expense
Interest on deposit liabilities									$ 5,348	$ 5,077	$ 5,092
Total interest expense									88,476	87,160	85,556
Provision for loan losses									6,275	6,126	1,507
Noninterest expense
Income before income taxes									254,788	265,598	249,836
Income taxes									93,021	95,579	86,237
Net income (loss)	$ 42,793	$ 51,144	$ 35,491	$ 32,339	$ 33,726	$ 48,279	$ 41,754	$ 46,260	161,767	170,019	163,599
American Savings Bank (ASB)
Interest and dividend income
Interest and fees on loans									184,782	179,341	172,969
Interest and dividends on investment securities									15,120	11,945	13,095
Total interest and dividend income									199,902	191,286	186,064
Interest expense
Interest on deposit liabilities									5,348	5,077	5,092
Interest on other borrowings									5,978	5,731	4,985
Total interest expense									11,326	10,808	10,077
Net interest income									188,576	180,478	175,987
Provision for loan losses									6,275	6,126	1,507
Net interest income after provision for loan losses									182,301	174,352	174,480
Noninterest income
Fees from other financial services									22,211	21,747	27,099
Fee income on deposit liabilities									22,368	19,249	18,363
Fee income on other financial products									8,094	8,131	8,405
Bank-owned life insurance									4,078	3,949	3,928
Mortgage banking income									6,330	2,913	8,309
Gain on sale of investment securities									0	2,847	1,226
Other income, net									4,750	2,375	4,753
Total noninterest income									67,831	61,211	72,083
Noninterest expense
Compensation and employee benefits									90,518	79,885	82,910
Occupancy									16,365	17,197	16,747
Data processing									12,103	11,690	10,952
Services									10,204	10,269	9,015
Equipment									6,577	6,564	7,295
Office supplies, printing and postage									5,749	6,089	4,233
Marketing									3,463	3,999	3,373
FDIC insurance									3,274	3,261	3,253
Other expense									18,067	17,314	19,637
Total noninterest expense									166,320	156,268	157,415
Income before income taxes									83,812	79,295	89,148
Income taxes									29,082	27,994	31,421
Net income (loss)									$ 54,730	$ 51,301	$ 57,727