Progressive Acquisition Pro Forma Financial Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Business Acquisition [Line Items]
Revenues, as reported	$ 759,742	$ 707,564	$ 672,510	$ 585,423	$ 553,852	$ 537,224	$ 550,545	$ 593,010	$ 2,725,239	$ 2,234,631	$ 2,212,827
Net earnings, as reported	22,094	9,295	8,505	38,339	22,674	21,138	25,854	51,000	78,233	120,666	173,043
Progressive Finance Holdings, LLC
Business Acquisition [Line Items]
Revenues, pro forma									2,894,413	2,638,582
Net earnings, pro forma									$ 86,038	$ 105,682