Long-Term Debt (Details) (USD $)	12 Months Ended
	Dec. 31, 2012
Minimum annual principal payments and repayments of the revolving advances [Abstract]
2013	$ 10,000,000
2014	12,500,000
2015	17,500,000
2016	20,000,000
2017	227,575,000
2018 and thereafter	0
Total	287,575,000
Fifth Amended Credit Agreement [Member]
Line of Credit Facility [Line Items]
Initiation date	Jun. 08, 2012
Maximum borrowing capacity	200,000,000
Expiration date	Jun. 08, 2017
Availability under the revolving credit facility under most restrictive covenant	55,000,000
Interest rate description	Borrowings under the Fifth Amended Credit Agreement generally bear interest at variable rates based on a margin or spread in excess of either (1) the one-month, two-month, three-month or six-month rate (or with the approval of affected lenders, nine-month or twelve-month rate) for Eurodollar deposits ( "LIBOR") or (2) the greatest of (a) the prime lending rate, (b) the federal funds rate plus 0.50%, and (c) one-month LIBOR plus 1.00% (the "Base Rate"), as selected by the Company. The LIBOR margin varies between 1.75% and 3.00%, and the Base Rate margin varies between 0.75% and 2.00%.
Unused commitments fees description	The Fifth Amended Credit Agreement also provides for an annual fee ranging between 0.30% and 0.50% of the unused commitments under the revolving credit facility.
Letters of Credit Sub Facility [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity	75,000,000
Swingline Sub Facility [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity	20,000,000
Term Loan Facility [Member]
Line of Credit Facility [Line Items]
Amount outstanding	195,000,000
Terms of periodic payments	We are required to repay outstanding revolving loans under the revolving credit facility on June 8, 2017. We are required to repay term loans in quarterly principal installments aggregating (1) 1.250% of the original aggregate principal amount of the term loans during each of the first eight quarters following the closing, (2) 1.875% of the original aggregate principal amount of the term loans during each of the next four quarters following the closing, (3) 2.500% of the original aggregate principal amount of the term loans during each of the remaining quarters prior to maturity on June 8, 2017, at which time the entire unpaid principal balance of the term loans is due and payable.
Maturity date	Jun. 08, 2017
Uncommitted Incremental Accordion Facility [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 200,000,000