CONSOLIDATING FINANCIAL STATEMENTS (Income and Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Condensed Statement of Income Captions [Line Items]
SALES	$ 200,890	$ 184,419	$ 649,991	$ 579,874
Costs and Expenses
Cost of sales	(143,261)	(136,983)	(466,167)	(418,421)
Selling and general expenses	(10,800)	(9,936)	(31,304)	(29,771)
Other operating (loss) income, net	(451)	1,771	2,577	3,744
Costs and Expenses, Total	(154,512)	(145,148)	(494,894)	(444,448)
OPERATING INCOME	46,378	39,271	155,097	135,426
Interest expense	(7,838)	(8,553)	(23,992)	(25,600)
Interest and miscellaneous income (expense), net	495	1,128	4,020	1,650
Equity in income from subsidiaries	0	0	0	0
INCOME BEFORE INCOME TAXES	39,035	31,846	135,125	111,476
Income tax expense	(8,396)	(3,043)	(22,443)	(16,817)
NET INCOME	30,639	28,803	112,682	94,659	$ 161,579
Less: Net income attributable to noncontrolling interest	(7,207)	(4,115)	(12,453)	(9,968)
NET INCOME ATTRIBUTABLE TO RAYONIER INC.	23,432	24,688	100,229	84,691
Foreign currency translation adjustment, net of income tax	(10,527)	(7,317)	(30,599)	16,599	9,114
Cash flow hedges, net of income tax	4,142	(2,162)	21,285	(1,597)	5,693
Amortization of pension and postretirement plans, net of income tax	(542)	116	(204)	349	$ (208)
Total other comprehensive (loss) income	(6,927)	(9,363)	(9,518)	15,351
COMPREHENSIVE INCOME	23,712	19,440	103,164	110,010
Less: Comprehensive income attributable to noncontrolling interest	(4,533)	(2,289)	(4,004)	(13,537)
COMPREHENSIVE INCOME ATTRIBUTABLE TO RAYONIER INC.	19,179	17,151	99,160	96,473
Consolidating Adjustments
Condensed Statement of Income Captions [Line Items]
SALES	0	0	0	0
Costs and Expenses
Cost of sales	0	0	0	0
Selling and general expenses	0	0	0	0
Other operating (loss) income, net	0	0	0	0
Costs and Expenses, Total	0	0	0	0
OPERATING INCOME	0	0	0	0
Interest expense	0	0	0	0
Interest and miscellaneous income (expense), net	0	0	0	0
Equity in income from subsidiaries	(58,366)	(59,270)	(231,339)	(199,328)
INCOME BEFORE INCOME TAXES	(58,366)	(59,270)	(231,339)	(199,328)
Income tax expense	0	0	0	0
NET INCOME	(58,366)	(59,270)	(231,339)	(199,328)
Less: Net income attributable to noncontrolling interest	0	0	0	0
NET INCOME ATTRIBUTABLE TO RAYONIER INC.	(58,366)	(59,270)	(231,339)	(199,328)
Foreign currency translation adjustment, net of income tax	8,090	5,866	23,341	(13,335)
Cash flow hedges, net of income tax	(4,379)	1,787	(22,476)	1,902
Amortization of pension and postretirement plans, net of income tax	542	(116)	204	(349)
Total other comprehensive (loss) income	4,253	7,537	1,069	(11,782)
COMPREHENSIVE INCOME	(54,113)	(51,733)	(230,270)	(211,110)
Less: Comprehensive income attributable to noncontrolling interest	0	0	0	0
COMPREHENSIVE INCOME ATTRIBUTABLE TO RAYONIER INC.	(54,113)	(51,733)	(230,270)	(211,110)
Rayonier Inc. (Parent Issuer) | Reportable Legal Entities
Condensed Statement of Income Captions [Line Items]
SALES	0	0	0	0
Costs and Expenses
Cost of sales	0	0	0	0
Selling and general expenses	0	0	0	0
Other operating (loss) income, net	0	0	(12)	0
Costs and Expenses, Total	0	0	(12)	0
OPERATING INCOME	0	0	(12)	0
Interest expense	(3,138)	(3,139)	(9,417)	(9,417)
Interest and miscellaneous income (expense), net	1,743	2,486	7,105	7,033
Equity in income from subsidiaries	24,827	25,341	102,553	87,075
INCOME BEFORE INCOME TAXES	23,432	24,688	100,229	84,691
Income tax expense	0	0	0	0
NET INCOME	23,432	24,688	100,229	84,691
Less: Net income attributable to noncontrolling interest	0	0	0	0
NET INCOME ATTRIBUTABLE TO RAYONIER INC.	23,432	24,688	100,229	84,691
Foreign currency translation adjustment, net of income tax	(8,090)	(5,866)	(23,341)	13,335
Cash flow hedges, net of income tax	4,379	(1,787)	22,476	(1,902)
Amortization of pension and postretirement plans, net of income tax	(542)	116	(204)	349
Total other comprehensive (loss) income	(4,253)	(7,537)	(1,069)	11,782
COMPREHENSIVE INCOME	19,179	17,151	99,160	96,473
Less: Comprehensive income attributable to noncontrolling interest	0	0	0	0
COMPREHENSIVE INCOME ATTRIBUTABLE TO RAYONIER INC.	19,179	17,151	99,160	96,473
Subsidiary Guarantors | Reportable Legal Entities
Condensed Statement of Income Captions [Line Items]
SALES	0	0	0	0
Costs and Expenses
Cost of sales	0	0	0	0
Selling and general expenses	(5,094)	(4,096)	(14,953)	(11,880)
Other operating (loss) income, net	(50)	(81)	545	(212)
Costs and Expenses, Total	(5,144)	(4,177)	(14,408)	(12,092)
OPERATING INCOME	(5,144)	(4,177)	(14,408)	(12,092)
Interest expense	(4,676)	(4,982)	(14,229)	(14,723)
Interest and miscellaneous income (expense), net	1,755	704	3,265	2,087
Equity in income from subsidiaries	33,539	33,929	128,786	112,253
INCOME BEFORE INCOME TAXES	25,474	25,474	103,414	87,525
Income tax expense	(647)	(133)	(861)	(450)
NET INCOME	24,827	25,341	102,553	87,075
Less: Net income attributable to noncontrolling interest	0	0	0	0
NET INCOME ATTRIBUTABLE TO RAYONIER INC.	24,827	25,341	102,553	87,075
Foreign currency translation adjustment, net of income tax	0	0	452	0
Cash flow hedges, net of income tax	5,174	(533)	26,460	(2,921)
Amortization of pension and postretirement plans, net of income tax	(542)	116	(204)	349
Total other comprehensive (loss) income	4,632	(417)	26,708	(2,572)
COMPREHENSIVE INCOME	29,459	24,924	129,261	84,503
Less: Comprehensive income attributable to noncontrolling interest	0	0	0	0
COMPREHENSIVE INCOME ATTRIBUTABLE TO RAYONIER INC.	29,459	24,924	129,261	84,503
Non- guarantors | Reportable Legal Entities
Condensed Statement of Income Captions [Line Items]
SALES	200,890	184,419	649,991	579,874
Costs and Expenses
Cost of sales	(143,261)	(136,983)	(466,167)	(418,421)
Selling and general expenses	(5,706)	(5,840)	(16,351)	(17,891)
Other operating (loss) income, net	(401)	1,852	2,044	3,956
Costs and Expenses, Total	(149,368)	(140,971)	(480,474)	(432,356)
OPERATING INCOME	51,522	43,448	169,517	147,518
Interest expense	(24)	(432)	(346)	(1,460)
Interest and miscellaneous income (expense), net	(3,003)	(2,062)	(6,350)	(7,470)
Equity in income from subsidiaries	0	0	0	0
INCOME BEFORE INCOME TAXES	48,495	40,954	162,821	138,588
Income tax expense	(7,749)	(2,910)	(21,582)	(16,367)
NET INCOME	40,746	38,044	141,239	122,221
Less: Net income attributable to noncontrolling interest	(7,207)	(4,115)	(12,453)	(9,968)
NET INCOME ATTRIBUTABLE TO RAYONIER INC.	33,539	33,929	128,786	112,253
Foreign currency translation adjustment, net of income tax	(10,527)	(7,317)	(31,051)	16,599
Cash flow hedges, net of income tax	(1,032)	(1,629)	(5,175)	1,324
Amortization of pension and postretirement plans, net of income tax	0	0	0	0
Total other comprehensive (loss) income	(11,559)	(8,946)	(36,226)	17,923
COMPREHENSIVE INCOME	29,187	29,098	105,013	140,144
Less: Comprehensive income attributable to noncontrolling interest	(4,533)	(2,289)	(4,004)	(13,537)
COMPREHENSIVE INCOME ATTRIBUTABLE TO RAYONIER INC.	$ 24,654	$ 26,809	$ 101,009	$ 126,607