Share-Based Awards - Stock Option Activity (Details) (2012 Plan, USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2013
2012 Plan
2012 Incentive Compensation Plan [Roll Forward]
Outstanding, January 1, 2013 (in shares)	1,722,700
Exercised (in shares)	(377,100)
Forfeitures and expired (in shares)	(8,300)
Outstanding, December 31, 2013 (in shares)	1,337,300
Vested or expected to vest (in shares)	1,323,900
Exercisable (in shares)	1,148,600
Weighted Average Exercise Price [Roll Forward]
Outstanding, January 1, 2013 (in dollars per share)	$ 19.41
Exercised (in dollars per share)	$ 20.09
Forfeited and expired (in dollars per share)	$ 21.21
Outstanding, December 31, 2013 (in dollars per share)	$ 19.21
Vested or expected to vest (in dollars per share)	$ 19.21
Exercisable (in dollars per share)	$ 18.87
Weighted Average Contractual Life [Abstract]
Weighted average contractual life, December 31, 2013	5 years 3 months 12 days
Vested or expected to vest weighted average contractual life (in years)	5 years 3 months 12 days
Weighted average contractual life, exercisable (in years)	4 years 10 months 12 days
Aggregate Intrinsic Value [Abstract]
Aggregate intrinsic value, December 31, 2013	$ 29,841
Vested and expected to vest aggregate intrinsic value	29,542
Aggregate intrinsic value, exercisable	$ 26,012

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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