Commitments and Contingencies (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Commitments and Contingencies [Line Items]
Rental expense for operating leases	$ 2,200,000	$ 2,500,000
Defined benefit plan employer matching contribution on first five percent of employee compensation	50.00%
Defined benefit plan employer contribution limit	6,000
Defined benefit plan employer contribution vesting period	5 years
Maximum [Member]
Commitments and Contingencies [Line Items]
Percentage of employees' eligible compensation for employer matching contribution	5.00%
Salaries And Related Expenses [Member]
Commitments and Contingencies [Line Items]
Defined benefit plan employer contribution	$ 300,000	$ 200,000