Stockholders' Equity (Details) (USD $) In Millions, unless otherwise specified	1 Months Ended	3 Months Ended
Sep. 30, 2012	Oct. 31, 2008	Mar. 31, 2014
Stockholders' Equity
Increase in maximum amount approved under common stock repurchase program	$ 10
Maximum amount authorized under the common stock repurchase program		10
Available authorized repurchase amount			$ 5.7

Represents the amount of increase in the amount authorized by an entity's Board of Directors under a stock repurchase plan.

No definition available.

Name:	pcmi_StockRepurchaseProgramIncreaseInAuthorizedAmount
Namespace Prefix:	pcmi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration