Pension and Other Postretirement Benefit Plans (Contributory employee savings plan) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Compensation and Retirement Disclosure [Abstract]
Matching contribution, contributory employee savings plan, amount	$ 486	$ 415	$ 379

Defined Contribution Plan, Employer Matching Contribution, Amount

No definition available.

Name:	mxwl_DefinedContributionPlanEmployerMatchingContributionAmount
Namespace Prefix:	mxwl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration