Commitments and Contingencies Commitments (Details) $ in Thousands	12 Months Ended
Jan. 31, 2018 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Long-term purchase commitment, amount	$ 5,000

The minimum amount the entity agreed to spend under the long-term purchase commitment.

No definition available.

Name:	us-gaap_LongTermPurchaseCommitmentAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration