Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Net income	$ 63,510	$ 57,693
Other comprehensive income adjustments:
Net unrealized gains on available-for-sale securities	44	1,058
Pension and postretirement benefits	450	342
Total other comprehensive income adjustments	494	1,400
Total comprehensive income	$ 64,004	$ 59,093

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

+ References+ Details

Before tax amount, net of reclassification adjustments, of the increase (decrease) in accumulated other comprehensive income (loss) related to pension and other postretirement benefit plans, attributable to the parent entity.

+ References

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+ Details

- Definition

Net of tax amount of other comprehensive income (loss) attributable to the parent entity.

+ References

+ Details

- Definition

Before tax and reclassification adjustments amount of unrealized holding gain (loss) and transfers on available-for-sale securities.

+ References

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