Accumulated Other Comprehensive Income (Loss) Accumulated Other Comprehensive Income (Loss) (Details) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2013	Dec. 31, 2012
Accumulated other comprehensive income [Line Items]
Accumulated other comprehensive income (loss), net of tax	$ (67,975,000)	$ (55,305,000)
Other comprehensive income loss net of tax before reclassification adjustments	(9,000,000)
Amounts reclassified from accumulated other comprehensive income loss	(3,700,000)
Net current period other comprehensive income loss	(12,700,000)
Tax On Unrealized Holding Gains Losses On Investments	1,800,000	2,500,000
Tax effect on unrealized gains (losses) on securities available for sale	700,000
Reclassification adjustments on securities available for sale	1,400,000
Tax On Unrealized Gains On Foreign Currency Forward Contracts	300,000	1,100,000
Tax effect on unrealized gains (losses) on foreign currency forward contracts	1,600,000
Reclassification adjustments on foreign currency forward contracts	100,000
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Accumulated other comprehensive income [Line Items]
Accumulated other comprehensive income (loss), net of tax	3,100,000	4,200,000
Other comprehensive income loss net of tax before reclassification adjustments	1,600,000
Amounts reclassified from accumulated other comprehensive income loss	(2,700,000)
Net current period other comprehensive income loss	(1,100,000)
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Accumulated other comprehensive income [Line Items]
Accumulated other comprehensive income (loss), net of tax	900,000	(10,700,000)
Other comprehensive income loss net of tax before reclassification adjustments	12,600,000
Amounts reclassified from accumulated other comprehensive income loss	(1,000,000)
Net current period other comprehensive income loss	11,600,000
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated other comprehensive income [Line Items]
Accumulated other comprehensive income (loss), net of tax	(20,500,000)	(21,700,000)
Other comprehensive income loss net of tax before reclassification adjustments	1,200,000
Amounts reclassified from accumulated other comprehensive income loss	0
Net current period other comprehensive income loss	1,200,000
Accumulated Translation Adjustment [Member]
Accumulated other comprehensive income [Line Items]
Accumulated other comprehensive income (loss), net of tax	(51,500,000)	(27,100,000)
Other comprehensive income loss net of tax before reclassification adjustments	(24,400,000)
Amounts reclassified from accumulated other comprehensive income loss	0
Net current period other comprehensive income loss	$ (24,400,000)