v2.4.0.8
Fair Value Measurements - Changes in Level 3 Financial Instruments (Details) (Fair Value, Measurements, Recurring [Member], Significant Unobservable Inputs (Level 3) [Member], USD $)
In Thousands, unless otherwise specified
 3 Months Ended 6 Months Ended
Jun. 30, 2013
Jun. 30, 2012
Jun. 30, 2013
Jun. 30, 2012
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Balance at beginning of period $ 3,220 $ 2,430 $ 2,901 $ 2,192
Net realized and unrealized gains – included in net income 0 9 118 19
Net realized and unrealized losses – included in net income (53) 0 0 0
Change in net unrealized gains – included in other comprehensive income 118 40 49 52
Change in net unrealized losses – included in other comprehensive income 0 0 0 0
Purchases 1,248 286 1,538 594
Sales and redemptions (95) (68) (168) (160)
Transfers into Level 3 0 0 0 0
Transfers out of Level 3 0 0 0 0
Balance at end of period 4,438 2,697 4,438 2,697
Level 3 gains (losses) included in net income attributable to the change in unrealized gains (losses) relating to assets held at the reporting date $ 0 $ 0 $ 0 $ 0