Parent Company - Condensed Statements of Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash flows from operating activities
Net income	$ 183,682	$ 230,178	$ 213,780
Adjustments to reconcile net income to net cash provided by operating activities:
Deferred income taxes	58,916	3,318	(15,587)
Stock-based compensation	5,292	4,507
Change in assets and liabilities:
Net decrease (increase) in other assets	(42,359)	(49,571)	(79,942)
Net decrease in other liabilities	(9,128)	(1,787)	528
Net cash provided by operating activities	269,774	220,093	142,603
Cash flows from investing activities
Other, net	(2,044)	94	90
Net cash provided by (used in) investing activities	(971,081)	(1,896,685)	243,832
Cash flows from financing activities
Dividends paid	(122,810)	(85,797)
Distributions paid	(2,118)	(361,200)	(164,228)
Stock tendered for payment of withholding taxes	(136)	(146)
Proceeds from employee stock purchase plan	528
Net cash provided by financing activities	683,893	78,455	1,002,307
Net increase (decrease) in cash and cash equivalents	(17,414)	(1,598,137)	1,388,742
Cash and cash equivalents at beginning of year	1,052,058	2,650,195	1,261,453
Cash and cash equivalents at end of year	1,034,644	1,052,058	2,650,195
Parent Company
Cash flows from operating activities
Net income	183,682	230,178	213,780
Adjustments to reconcile net income to net cash provided by operating activities:
(Equity in undistributed income) excess distributions of FHB	(85,205)	239,810	(49,552)
Deferred income taxes	(274)	191
Stock-based compensation	244	55
Change in assets and liabilities:
Net decrease (increase) in other assets	36,467	(18,729)
Net decrease in other liabilities	(2,058)	(8,368)
Net cash provided by operating activities	132,856	443,137	164,228
Cash flows from investing activities
Other, net	7
Net cash provided by (used in) investing activities	7
Cash flows from financing activities
Dividends paid	(122,810)	(85,797)
Distributions paid	(2,118)	(361,200)	(164,228)
Stock tendered for payment of withholding taxes	(120)	(146)
Proceeds from employee stock purchase plan	528
Net cash provided by financing activities	(124,520)	(447,143)	(164,228)
Net increase (decrease) in cash and cash equivalents	8,343	(4,006)
Cash and cash equivalents at beginning of year	5,994	10,000	10,000
Cash and cash equivalents at end of year	$ 14,337	$ 5,994	$ 10,000