Revolving Credit Facility and Long-Term Debt - Narrative (Details) (USD $)	12 Months Ended																0 Months Ended
	Dec. 31, 2012 Credit Agreement [Member] quarter	Dec. 31, 2011 Credit Agreement [Member]	Dec. 31, 2012 Base Rate [Member] Credit Agreement [Member]	Dec. 19, 2012 Base Rate [Member] Credit Agreement [Member]	Dec. 31, 2012 London Interbank Offered Rate (LIBOR) Market Index Rate [Member] Credit Agreement [Member]	Dec. 19, 2012 London Interbank Offered Rate (LIBOR) Market Index Rate [Member] Credit Agreement [Member]	Dec. 31, 2012 London Interbank Offered Rate (LIBOR) [Member] Credit Agreement [Member]	Dec. 19, 2012 London Interbank Offered Rate (LIBOR) [Member] Credit Agreement [Member]	Dec. 31, 2012 Federal Funds Rate [Member] Credit Agreement [Member]	Dec. 31, 2012 Variable Rate 1 [Member] Credit Agreement [Member]	Dec. 31, 2011 Variable Rate 1 [Member] Credit Agreement [Member]	Dec. 31, 2012 Variable Rate 2 [Member] Credit Agreement [Member]	Dec. 31, 2011 Variable Rate 2 [Member] Credit Agreement [Member]	Dec. 19, 2012 Revolving Credit Facility [Member] Credit Agreement [Member]	Sep. 30, 2010 Revolving Credit Facility [Member] Wells Fargo [Member]	Dec. 07, 2006 Revolving Credit Facility [Member] Bank of America [Member]	Dec. 19, 2012 Term Loan [Member] Credit Agreement [Member]	Dec. 31, 2012 Bridge Loan [Member] Base Rate [Member] Credit Agreement [Member]	Dec. 31, 2012 Bridge Loan [Member] London Interbank Offered Rate (LIBOR) Market Index Rate [Member] Credit Agreement [Member]	Dec. 19, 2012 Bridge Loan [Member] London Interbank Offered Rate (LIBOR) Market Index Rate [Member] Credit Agreement [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity														$ 175,000,000	$ 125,000,000	$ 30,000,000	$ 100,000,000
Line of Credit Facility, Periodic Payment																	2,500,000
Debt Instrument, Basis Spread on Variable Rate			0.25%	1.00%	1.25%	2.00%	1.25%	2.00%											1.25%	2.00%
Debt Instrument, Basis Spread on Base Rate							0.01		0.0050
Line of Credit Facility, Covenant Terms, Consolidated Total Leverage Ratio, Next Twelve Months, Maximum	3.5
Line of Credit Facility, Covenant Terms, Consolidated Total Leverage Ratio, Year Two, Maximum	3.35
Line of Credit Facility, Covenant Terms, Consolidated Total Leverage Ratio, Year Three, Maximum	3
Line of Credit Facility, Covenant Terms, Consolidated Total Leverage Ratio, Year Four, Maximum	2.75
Line of Credit Facility, Covenant Terms, Consolidated Total Leverage Ratio, Year Five, Maximum	2.5
Line of Credit Facility, Covenant Terms, Consolidated EBITDA to Fixed Charges Ratio, Number of Consecutive Quarters	4
Line of Credit Facility, Covenant Terms, Consolidated EBITDA to Fixed Charges Ratio, Minimum	1.75
Line of Credit Facility, Covenant Terms, Consolidated Net Income, Maximum	0
Line of Credit Facility, Covenant Terms, Facility Capital Expenditures, Next Twelve Months, Maximum	30,000,000
Line of Credit Facility, Covenant Terms, Consolidated Total Leverage Ratio, Minimum			2.25		2.25		2.25											2.25
Line of Credit Facility, Remaining Borrowing Capacity	33,800,000
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	2.98%	1.54%
Long-term Debt, Percentage Bearing Fixed Interest, Amount	150,000,000	24,000,000
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate										2.22%	1.55%	2.31%	1.84%
Long-term Debt, Percentage Bearing Variable Interest, Amount										$ 87,000,000	$ 5,000,000	$ 566,000	$ 1,700,000