XML 98 R66.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Common Stock and Earnings per Share (Narrative) (Details) | 12 Months Ended
--- | ---
Dec. 31, 2013
Common Stock and Earnings per Share [Abstract] |
Stock dividend, percent | 10.00%

X
- Definition The percentage rate used to calculate dividend payments on common stock. + References No definition available. + Details
Name: | cass_CommonStockDividendRatePercentage
Namespace Prefix: | cass_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_EarningsPerShareAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration