Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Jul. 31, 2020	Jan. 31, 2020	Jul. 31, 2019
Assets:
Total assets measured at fair value	$ 72,409	$ 71,158	$ 76,155
Liabilities:
Total liabilities measured at fair value	45,043	45,264	44,269
Level 1
Assets:
Total assets measured at fair value	46,274	46,584	43,771
Liabilities:
Total liabilities measured at fair value	45,043	45,264	42,298
Level 2
Assets:
Total assets measured at fair value	228	347	140
Liabilities:
Total liabilities measured at fair value	0	0	71
Level 3
Assets:
Total assets measured at fair value	25,907	24,227	32,244
Liabilities:
Total liabilities measured at fair value	0	0	1,900
Other Current Assets | Available-for-sale securities
Assets:
Total assets measured at fair value	141	184	187
Other Current Assets | Short-term investment
Assets:
Total assets measured at fair value	155	156	156
Other Current Assets | Hedge derivatives-Assets
Assets:
Total assets measured at fair value	228	347	140
Other Current Assets | Level 1 | Available-for-sale securities
Assets:
Total assets measured at fair value	141	184	187
Other Current Assets | Level 1 | Short-term investment
Assets:
Total assets measured at fair value	155	156	156
Other Current Assets | Level 1 | Hedge derivatives-Assets
Assets:
Total assets measured at fair value	0	0	0
Other Current Assets | Level 2 | Available-for-sale securities
Assets:
Total assets measured at fair value	0	0	0
Other Current Assets | Level 2 | Short-term investment
Assets:
Total assets measured at fair value	0	0	0
Other Current Assets | Level 2 | Hedge derivatives-Assets
Assets:
Total assets measured at fair value	228	347	140
Other Current Assets | Level 3 | Available-for-sale securities
Assets:
Total assets measured at fair value	0	0	0
Other Current Assets | Level 3 | Short-term investment
Assets:
Total assets measured at fair value	0	0	0
Other Current Assets | Level 3 | Hedge derivatives-Assets
Assets:
Total assets measured at fair value	0	0	0
Other Non-current Assets | SERP assets - employer
Assets:
Total assets measured at fair value	935	988	1,130
Other Non-current Assets | SERP assets - employee
Assets:
Total assets measured at fair value	45,043	45,256	42,298
Other Non-current Assets | Level 1 | SERP assets - employer
Assets:
Total assets measured at fair value	935	988	1,130
Other Non-current Assets | Level 1 | SERP assets - employee
Assets:
Total assets measured at fair value	45,043	45,256	42,298
Other Non-current Assets | Level 2 | SERP assets - employer
Assets:
Total assets measured at fair value	0	0	0
Other Non-current Assets | Level 2 | SERP assets - employee
Assets:
Total assets measured at fair value	0	0	0
Other Non-current Assets | Level 3 | SERP assets - employer
Assets:
Total assets measured at fair value	0	0	0
Other Non-current Assets | Level 3 | SERP assets - employee
Assets:
Total assets measured at fair value	0	0	0
Other non-current liabilities | SERP liabilities - employee
Liabilities:
Total liabilities measured at fair value	45,043	45,264	42,298
Other non-current liabilities | Contingent Consideration
Liabilities:
Total liabilities measured at fair value			1,900
Other non-current liabilities | Defined Benefit Plan Assets
Assets:
Total assets measured at fair value	25,907	24,227	32,244
Other non-current liabilities | Level 1 | SERP liabilities - employee
Liabilities:
Total liabilities measured at fair value	45,043	45,264	42,298
Other non-current liabilities | Level 1 | Contingent Consideration
Liabilities:
Total liabilities measured at fair value			0
Other non-current liabilities | Level 1 | Defined Benefit Plan Assets
Assets:
Total assets measured at fair value	0	0	0
Other non-current liabilities | Level 2 | SERP liabilities - employee
Liabilities:
Total liabilities measured at fair value	0	0	0
Other non-current liabilities | Level 2 | Contingent Consideration
Liabilities:
Total liabilities measured at fair value			0
Other non-current liabilities | Level 2 | Defined Benefit Plan Assets
Assets:
Total assets measured at fair value	0	0	0
Other non-current liabilities | Level 3 | SERP liabilities - employee
Liabilities:
Total liabilities measured at fair value	0	0	0
Other non-current liabilities | Level 3 | Contingent Consideration
Liabilities:
Total liabilities measured at fair value			1,900
Other non-current liabilities | Level 3 | Defined Benefit Plan Assets
Assets:
Total assets measured at fair value	$ 25,907	$ 24,227	32,244
Accrued Liabilities | Hedge derivatives-Liabilities
Liabilities:
Total liabilities measured at fair value			71
Accrued Liabilities | Level 1 | Hedge derivatives-Liabilities
Liabilities:
Total liabilities measured at fair value			0
Accrued Liabilities | Level 2 | Hedge derivatives-Liabilities
Liabilities:
Total liabilities measured at fair value			71
Accrued Liabilities | Level 3 | Hedge derivatives-Liabilities
Liabilities:
Total liabilities measured at fair value			$ 0