Supplemental Cash Flow Information (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Non-cash financing and investing activities:
Capital expenditures	$ 1,183	[1]	$ 3,402	[1]	$ 2,936	[1]
Capital lease obligations	0		1,857		4,510
Non-cash capitalized interest	2,694		845		681
Non-cash acquisitions and related deferred taxes	317,826		64,133		0
Other cash flow information:
Interest paid	14,139		6,092		11,033
Capitalized interest	2,694		2,663		2,175
Income taxes paid	$ 26,585		$ 54,680		$ 44,396

[1] Accrued capital expenditures are recognized in the consolidated statements of cash flows in the period in which they are paid.